Pathologists, Pediatric Specialist
33 years of experience

Accepting new patients
Northwest Dallas
Children S Med Ctr-Dept Of Pathology
1935 Medical District Dr
Dallas, TX 75235
214-456-2320
Locations and availability (3)

Education ?

Medical School Score Rankings
University of North Carolina (1977)
  • Currently 4 of 4 apples
Top 25%

Awards & Distinctions ?

Awards  
Medical Student Teaching Award (2006)
Medical Student Teaching Award (2002)
Medical Student Teaching Award (2004)
Associations
American Board of Pathology

Affiliations ?

Dr. Timmons is affiliated with 5 hospitals.

Hospital Affilations

Score

Rankings

  • Children's Medical Center of Dallas
    1935 Motor St, Dallas, TX 75235
    • Currently 4 of 4 crosses
    Top 25%
  • UT Southwestern Zale Lipshy Hospital
  • UT Southwestern St Paul Hospital
  • Parkland Health & Hospital System
  • Univ TX Southwestern Med Ctr
    5323 Harry Hines Blvd, Dallas, TX 75390
  • Publications & Research

    Dr. Timmons has contributed to 48 publications.
    Title Imaging Characteristics of Atypical Teratoid-rhabdoid Tumor in Children Compared with Medulloblastoma.
    Date April 2008
    Journal Ajr. American Journal of Roentgenology
    Excerpt

    OBJECTIVE: The purpose of our study was to compare the imaging characteristics of atypical teratoid-rhabdoid tumor with medulloblastoma and seek distinguishing features that can aid in preoperative diagnosis. MATERIALS AND METHODS: Preoperative MRI examinations of 55 patients (36 medulloblastomas and 19 atypical teratoid-rhabdoid tumors) were analyzed retrospectively. Imaging characteristics of atypical teratoid-rhabdoid tumor and medulloblastoma were assessed with conventional MRI and CT. Diffusion-weighted imaging (DWI) was available in 27 patients (19 medulloblastomas and eight atypical teratoid-rhabdoid tumors). Apparent diffusion coefficient (ADC) values were calculated for 14 medulloblastomas and six atypical teratoid-rhabdoid tumors. RESULTS: Both atypical teratoid-rhabdoid tumors in general and infratentorial atypical teratoid-rhabdoid tumors presented at a younger age than medulloblastomas. Eleven of 19 atypical teratoid-rhabdoid tumors were infratentorial. Cerebellopontine angle (CPA) involvement was more frequent (8/11, 72.7%) in atypical teratoid-rhabdoid tumor than in medulloblastoma (4/36, 11.1%) (p < 0.001). Intratumoral hemorrhage was more common in atypical teratoid-rhabdoid tumor (9/19, 47.4%) than in medulloblastoma (2/36, 5.6%) (p < 0.0001). All atypical teratoid-rhabdoid tumors and all medulloblastomas for which DWI was available displayed increased signal intensity on DWI compared with normal brain parenchyma. The mean ADC values for tumor types were not significantly different. CONCLUSION: Atypical teratoid-rhabdoid tumor presents at a younger age than medulloblastoma. Although atypical teratoid-rhabdoid tumor and medulloblastoma display similar imaging characteristics on conventional MRI, CPA involvement and intratumoral hemorrhage are more common in atypical teratoid-rhabdoid tumor. If a pediatric posterior fossa mass that displays restricted diffusion is involving the CPA, atypical teratoid-rhabdoid tumor is a more likely consideration than medulloblastoma.

    Title A Severely Affected Female Infant with X-linked Dominant Chondrodysplasia Punctata: a Case Report and a Brief Review of the Literature.
    Date May 2007
    Journal Pediatric and Developmental Pathology : the Official Journal of the Society for Pediatric Pathology and the Paediatric Pathology Society
    Excerpt

    We recently performed an autopsy on a premature female newborn with rhizomesoacromelic limb shortening of the upper and lower extremities, craniofacial dysmorphism, and chondrodysplasia punctata. A diagnosis of Conradi-Hunermann-Happle syndrome or X-linked dominant chondrodysplasia punctata was made based on elevated cholest-8(9)-ene-3beta-ol in serum and tissues. Molecular analysis of EBP, mutations of which are responsible for this malformation syndrome, revealed a monoallelic missense mutation, c.328 G>A (R110Q). We present this case as an illustration of an unusually severe manifestation of this disorder in a female, with additional unusual features including lack of skin manifestations and apparent bilateral symmetry of the skeletal findings.

    Title Absence of Expression of Smarcb1/ini1 in Malignant Rhabdoid Tumors of the Central Nervous System, Kidneys and Soft Tissue: an Immunohistochemical Study with Implications for Diagnosis.
    Date July 2006
    Journal Modern Pathology : an Official Journal of the United States and Canadian Academy of Pathology, Inc
    Excerpt

    Malignant rhabdoid tumors are high-grade neoplasms of the central nervous system (CNS), kidneys and soft tissue that usually occur in children. The histologic diagnosis of malignant rhabdoid tumor depends on identification of characteristic rhabdoid cells-large cells with eccentrically located nuclei and abundant, eosinophilic cytoplasm-and immunohistochemistry with antibodies to vimentin, keratin and epithelial membrane antigen. In most malignant rhabdoid tumors, the SMARCB1/INI1 gene, located in chromosome band 22q11.2, is inactivated by deletions and/or mutations, so genetic diagnosis is often possible. However, tissue may not be available for genetic analysis or studies not confirmatory. We assessed SMARCB1/INI1 expression in 17 rhabdoid tumors and 57 other tumors of the CNS, kidney or soft tissue using immunohistochemistry. In total, 12 brain, three renal and two soft tissue rhabdoid tumors were examined along with four glioblastomas, four pilocytic astrocytomas, four oligodendrogliomas, two ependymomas, two choroid plexus papillomas, five pituitary adenomas, four germinomas, four renal carcinomas with Xp11.2 translocations, two clear cell sarcomas, two Wilms' tumors, one renal medullary carcinoma, two desmoplastic small round cell tumors, two alveolar rhabdomyosarcomas, two embryonal rhabdomyosarcomas, one low-grade chondrosarcoma, two extraskeletal myxoid chondrosarcomas, one mesenchymal chondrosarcoma, four malignant peripheral nerve sheath tumors, five metastatic carcinomas and four epithelioid sarcomas, two primary and two metastatic. The neoplastic cells of all rhabdoid tumors, the four epithelioid sarcomas and the renal medullary carcinoma did not express SMARCB1/INI1 by immunohistochemistry; neoplastic cells of all other tumors expressed SMARCB1/INI1. Immunohistochemistry to assess expression of SMARCB1/INI1 may be useful in the diagnosis of rhabdoid tumors of the CNS, kidneys and soft tissue.

    Title Helicobacter Heilmannii Infection in a Child.
    Date May 2005
    Journal Archives of Pathology & Laboratory Medicine
    Title Extrapleural Benign Solitary Fibrous Tumor in the Shoulder of a 9-year-old Girl: Case Report and Review of the Literature.
    Date May 2005
    Journal Pediatric and Developmental Pathology : the Official Journal of the Society for Pediatric Pathology and the Paediatric Pathology Society
    Excerpt

    We report a case of a benign solitary fibrous tumor that occurred in the right shoulder of a 9-year-old girl. This case is remarkable due to the unusual location of its occurrence and the young age of the patient. In addition, cytogenetic analysis revealed a karyotype unreported in this neoplasm: 46,XX,der(4)t(4;9)(q31.1;q34), del(9)(p22p24),der(9)t(4;9)(q31.1;q34)ins(9;?)(q34;?) (17 cells)/46,XX (3 cells).

    Title Aberrant Methylation of the Hic1 Promoter is a Frequent Event in Specific Pediatric Neoplasms.
    Date May 2004
    Journal Clinical Cancer Research : an Official Journal of the American Association for Cancer Research
    Excerpt

    PURPOSE: To determine the role of methylation of HIC1, a candidate tumor suppressor gene on 17p13.3, in various types of pediatric tumors. EXPERIMENTAL DESIGN: We examined the methylation status of the HIC1 promoter by methylation specific PCR in 157 pediatric tumors and 27 nonmalignant tissues. We correlated methylation with mRNA expression by reverse transcription-PCR in eight tumor-derived cell lines. RESULTS: HIC1 methylation was frequent in medulloblastomas (80%, 12 of 15), retinoblastomas (67%, 6 of 9), rhabdomyosarcomas (59%, 13 of 22), germ cell tumors (55%, 6 of 11), and neurouroblastic tumors (36%, 14 of 39); neuroblastomas (43%, 12 of 28); ganglioneuromas (17%, 1 of 6); and ganglioneuroblastomas (20%, 1 of 5). In contrast, a low incidence of methylation was observed in osteosarcomas (17%, 2 of 12), Ewing's tumors (9%, 1 of 11), Wilms' tumors (3%, 1 of 31), and hepatoblastomas (0%, 0 of 7). HIC1 methylation was more frequent in the aggressive alveolar subtype of rhabdomyosarcomas (100%, 8 of 8) than the embryonal subtype (33%, 4 of 12; P < 0.005) and was rare in the nonmalignant tissues examined. Methylation was also demonstrated by sequencing in nine randomly selected tumor samples. Seven of eight pediatric tumor cell lines examined were methylated and showed loss or reduced HIC1 mRNA. Expression was strongly induced in all cell lines by treatment with the demethylating agent 5-aza 2'deoxycytidine. CONCLUSIONS: Our data suggest that aberrant methylation of HIC1 may play a role in the pathogenesis of specific pediatric tumors.

    Title The Epidermal Growth Factor Receptor Her2 is Not a Major Therapeutic Target in Ewing Sarcoma.
    Date July 2003
    Journal Journal of Pediatric Hematology/oncology : Official Journal of the American Society of Pediatric Hematology/oncology
    Excerpt

    BACKGROUND: Although chimeric EWS gene and Ets gene fusions are pathognomonic of Ewing sarcoma (ES) and primitive neuroectodermal tumors (PNET), the molecular pathogenesis of these pediatric malignancies is poorly understood. Recently, the human epidermal growth factor (HER)-2 receptor, which plays an important role in the biology of certain epithelial cancers, has been implicated in ES tumor cell line growth and chemosensitivity. MATERIALS: To investigate whether HER2 might be a rational target for ES/PNET therapy, five ES cell lines and 13 archival primary ES/PNET samples were examined by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) for evidence of HER2 overexpression. RESULTS: Although several ES cell lines demonstrated modest constitutive HER2 expression by immunoblot, none of the ES cell lines or primary tumor samples showed evidence of HER2 overexpression by IHC or HER2 gene amplification by FISH. Moreover, treatment of human ES cell lines with the HER2-targeted agent trastuzumab (Herceptin) had little effect on cell survival, proliferation, or growth in semi-solid medium. CONCLUSIONS: These results suggest that HER2 is not a biologically or therapeutically important pathway in ES/PNET.

    Title Etv6-ntrk3--trk-ing the Primary Event in Human Secretory Breast Cancer.
    Date July 2003
    Journal Cancer Cell
    Excerpt

    In this issue of Cancer Cell, propose a single chromosomal translocation as the cause of a particularly troubling form of breast cancer, secretory carcinoma. They challenge widely held beliefs concerning breast carcinogenesis as well as beliefs concerning the absolute association of specific fusion genes with specific tumor types. Their data highlight the role of Trk signaling in breast cancer and also suggest a target for drug development.

    Title Rapidly Fatal Acute Bacterial Myocarditis in a Nonneutropenic Child with Acute Lymphoblastic Leukemia in Remission.
    Date December 2002
    Journal Journal of Pediatric Hematology/oncology : Official Journal of the American Society of Pediatric Hematology/oncology
    Excerpt

    The authors report a fatal case of acute bacterial myocarditis in a nonneutropenic child with acute lymphoblastic leukemia. She was admitted to the hospital with a urinary tract infection resulting from and remained persistently febrile despite resolution of the infection. On hospital day 4 signs of acute cardiac failure developed. Despite aggressive resuscitation measures, she died. Pathologic examination revealed the cause of death to be bacterial myocarditis. In addition, she was found to have a generalized decrease in her serum immunoglobulin levels. Acute bacterial myocarditis in patients with malignancy has been rarely reported. The rapid clinical deterioration and death in the patient in this report is particularly interesting.

    Title Laryngeal Duplication Cyst.
    Date December 2002
    Journal Archives of Otolaryngology--head & Neck Surgery
    Excerpt

    Benign congenital laryngeal cysts are rare. Infants and children with these lesions can present with chronic or intermittent airway obstructive symptoms, hoarseness, aspiration, chronic cough, or failure to thrive. The most common congenital laryngeal cysts include saccular cysts, laryngoceles, and ductal cysts. Other more unusual laryngeal lesions, such as hamartomas, choristomas, and teratomas, can also present with these symptoms. We describe a unique congenital cyst that arose in continuity with the larynx in a child with hoarseness and intermittent stridor. The features of this lesion are similar to those of bronchogenic duplication cysts of the trachea, but with histopathological features of the larynx.

    Title Deregulation of Caspase 8 and 10 Expression in Pediatric Tumors and Cell Lines.
    Date November 2002
    Journal Cancer Research
    Excerpt

    Methylation of the promoter regions of CpG-rich sites in genes is the major mechanism for the silencing of many genes in tumors. Methylation of the key apoptosis-related gene caspase 8 (CASP8) has been reported in some childhood tumors and in neuroendocrine lung tumors. We examined the methylation status of 181 pediatric tumors and found frequent methylation in rhabdomyosarcomas (83%), medulloblastomas (81%), retinoblastomas (59%), and neuroblastomas (52%). Methylation frequencies were low in Wilms' tumors (19%) and absent in hepatoblastomas, acute leukemias, osteosarcomas, Ewing's sarcomas, and ganglioneuromas and in normal tissues. Methylation of CASP8 and the tumor suppressor gene RASSF1A were highly significantly correlated in all tumor types by both the chi(2) and the Fisher's exact tests (P < 0.0001 for both tests). Because the region of the gene examined by us and others is not located in the promoter region and lacks features of a CpG island, we explored the relationship between methylation and gene silencing in detail using 23 pediatric tumor cell lines. Studies included relating the methylation of the region to gene expression at mRNA and protein levels, enzymatic assays of gene function, clonal analysis of PCR amplicons of the region, and exposure to a demethylating agent. These studies indicated that methylation correlated with the loss of gene function in most cases; however, other mechanisms of gene inactivation were present in some cases. Posttranscriptional inactivation of the closely related gene caspase 10 was present in many cell lines. Our results suggest that deregulation of the death receptor pathway to apoptosis is frequent in many types of pediatric tumors and their cell lines.

    Title Effects of Orchiopexy on Congenitally Cryptorchid Insulin-3 Knockout Mice.
    Date October 2002
    Journal The Journal of Urology
    Excerpt

    PURPOSE: Insulin-3 (Insl3) knockout mice exhibit isolated, bilateral, high intra-abdominal cryptorchidism. If left in this position until adulthood, these testes will deteriorate to the Sertoli-cell-only state, leading to infertility in 100%. We examined the effect of orchiopexy in this genetically engineered animal model. MATERIALS AND METHODS: A total of 160 testes from 80 male offspring of Insl3 F crosses underwent either no orchiopexy (29 testes), sham surgery (25 testes), 1-stage Fowler-Stephens scrotal orchiopexy (57 testes) or primary orchiopexy into a low abdominal, subcutaneous pouch (49 testes). A group of postoperative mice underwent fertility testing 3 months postoperatively. At 6 to 9 months postoperatively the testes were harvested and histologically analyzed. RESULTS: Testes were atrophic in 100% (25 of 25) of the sham group, 91% (52 of 57) of the Fowler-Stephens orchiopexy group and 33% (16 of 49) of the subcutaneous pouch group (testis weight less than 50 mg.). Fertility testing was done in 30 mice (sham 5, Fowler-Stephens orchiopexy 17 and subcutaneous pouch 8). Infertility was secondary to bilateral testicular atrophy (sham 5 of 5, Fowler-Stephens orchiopexy 13 of 17), spermatogenic maturation arrest (subcutaneous pouch 8 of 8) and ductal obstruction [normal spermatogenesis with epididymis devoid of sperm] (Fowler-Stephens orchiopexy 2 of 17). Fertility with normal spermatogenesis was observed in 2 of 17 Fowler-Stephens orchiopexy mice, both of which were Insl3 knockout mice. CONCLUSIONS: Intrascrotal orchiopexy can rescue these congenitally cryptorchid Insl3 knockout testes from their intra-abdominal fate of Sertoli-cell-only and lead to fertility. The results suggest that orchiopexy has a crucial and central role in preservation of spermatogenesis.

    Title Aberrant Promoter Methylation and Silencing of the Rassf1a Gene in Pediatric Tumors and Cell Lines.
    Date July 2002
    Journal Oncogene
    Excerpt

    Aberrant promoter methylation of tumor suppressor genes has not been fully investigated in pediatric tumors. Therefore, we examined the methylation status of nine genes (p16(INK4A), MGMT, GSTP1, RASSF1A, APC, DAPK, RARbeta, CDH1 and CDH13) in 175 primary pediatric tumors and 23 tumor cell lines using methylation-specific PCR. We studied the major forms of pediatric tumors--Wilms' tumor, neuroblastoma, hepatoblastoma, medulloblastoma, rhabdomyosarcoma, osteosarcoma, Ewing's sarcoma, retinoblastoma and acute leukemia. The most frequently methylated gene in both primary tumors and cell lines was RASSF1A (40, 86%, respectively). However, the rates of RASSF1A methylation in individual tumor types varied from 0 to 88%. RASSF1A methylation was tumor specific and was absent in adjacent non-malignant tissues. Methylation of the other genes was relatively rare in tumors and non-malignant tissues (less than 5%). Neuroblastoma patients with methylation of RASSF1A were significantly older than patients without methylation (P=0.008). There was no relationship between methylation status and other clinico-pathologic parameters. We treated six cell lines lacking RASSF1A mRNA with 5-aza-2'deoxycytidine to examine the relationship between methylation and transcriptional silencing. In five of six cell lines, restoration of RASSF1A mRNA was confirmed by RT-PCR. Our findings indicate that aberrant promoter methylation of RASSF1A may contribute to the pathogenesis of many different forms of pediatric tumors.

    Title Fine-needle Aspiration Biopsy Features in a Case of Giant Cell Fibroblastoma of the Chest Wall.
    Date August 2001
    Journal Archives of Pathology & Laboratory Medicine
    Excerpt

    Giant cell fibroblastoma is an unusual tumor of childhood, primarily occurring in the superficial soft tissues. We describe the fine-needle aspiration biopsy features of a case of giant cell fibroblastoma of the chest wall in a 3-year-old child. The aspirates comprised bland spindle to oval cells entrapped in a metachromatic matrix, accompanied by rare multinucleated giant cells with wreathlike nuclei. Although we were unable to render a definitive diagnosis on fine-needle aspiration biopsy, surgical resection of the mass established the diagnosis of giant cell fibroblastoma. We review the distinctive cytologic features of some common soft tissue tumors arising in this age group that may give rise to a diagnostic conundrum on fine-needle aspiration biopsy.

    Title Primary Renal Neoplasms with the Aspl-tfe3 Gene Fusion of Alveolar Soft Part Sarcoma: a Distinctive Tumor Entity Previously Included Among Renal Cell Carcinomas of Children and Adolescents.
    Date August 2001
    Journal The American Journal of Pathology
    Excerpt

    The unbalanced translocation, der(17)t(X;17)(p11.2;q25), is characteristic of alveolar soft part sarcoma (ASPS). We have recently shown that this translocation fuses the TFE3 transcription factor gene at Xp11.2 to ASPL, a novel gene at 17q25. We describe herein eight morphologically distinctive renal tumors occurring in young people that bear the identical ASPL-TFE3 fusion transcript as ASPS, with the distinction that the t(X;17) translocation is cytogenetically balanced in these renal tumors. A relationship between these renal tumors and ASPS was initially suggested by the cytogenetic finding of a balanced t(X;17)(p11.2;q25) in two of the cases, and the ASPL-TFE3 fusion transcripts were then confirmed by reverse transcriptase-polymerase chain reaction. The morphology of these eight ASPL-TFE3 fusion-positive renal tumors, although overlapping in some aspects that of classic ASPS, more closely resembles renal cell carcinoma (RCC), which was the a priori diagnosis in all cases. These tumors demonstrate nested and pseudopapillary patterns of growth, psammomatous calcifications, and epithelioid cells with abundant clear cytoplasm and well-defined cell borders. By immunohistochemistry, four tumors were negative for all epithelial markers tested, whereas four were focally positive for cytokeratin and two were reactive for epithelial membrane antigen (EMA) (one diffusely, one focally). Electron microscopy of six tumors demonstrated a combination of ASPS-like features (dense granules in four cases, rhomboid crystals in two cases) and epithelial features (cell junctions in six cases, microvilli and true glandular lumens in three cases). Overall, although seven of eight tumors demonstrated at least focal epithelial features by electron microscopy or immunohistochemistry, the degree and extent of epithelial differentiation was notably less than expected for typical RCC. We confirmed the balanced nature of the t(X;17) translocation by fluorescence in situ hybridization in all seven renal tumors thus analyzed, which contrasts sharply with the unbalanced nature of the translocation in ASPS. In summary, a subset of tumors previously considered to be RCC in young people are in fact genetically related to ASPS, although their distinctive morphological and genetic features justify their classification as a distinctive neoplastic entity. Finally, the finding of distinctive tumors being associated with balanced and unbalanced forms of the same translocation is to our knowledge, unprecedented.

    Title Mutations of the Hsnf5/ini1 Gene in Renal Rhabdoid Tumors with Second Primary Brain Tumors.
    Date May 2000
    Journal Journal of the National Cancer Institute
    Title Bannayan-riley-ruvalcaba Syndrome: Spectrum of Intestinal Pathology Including Juvenile Polyps.
    Date March 2000
    Journal Pediatric and Developmental Pathology : the Official Journal of the Society for Pediatric Pathology and the Paediatric Pathology Society
    Excerpt

    Bannayan-Riley-Ruvalcaba syndrome (BRRS) is a disorder that includes juvenile polyposis as part of its pathologic spectrum, and it recently has been shown to share phenotypic and genotypic features with Cowden's disease. In existing literature, descriptions of intestinal pathology in patients with BRRS are relatively sparse and occasionally erroneous. We describe the intestinal pathology in multiple specimens from three children with BRRS. Examination of gastrointestinal biopsies from these children revealed predominantly colonic and rectal polyps with the histology of juvenile polyps. Additionally, two cases with clusters of ectopic ganglion cells within the lamina propria, one in a colonic polyp and one in a duodenal biopsy, and an atypical polyp were observed. Bannayan-Riley-Ruvalcaba syndrome should be included in the list of differential diagnostic considerations when a child or young adult presents with a juvenile polyp, particularly if unusual histologic features such as atypical polyps or ectopic ganglion cells are encountered.

    Title Double Heterozygosity for Hb G-san Jose [beta7(a4)glu-->gly] and Hb Fukuoka [beta2(na2)his-->tyr] in a 2 1/2-year-old Girl.
    Date December 1999
    Journal Hemoglobin
    Title Relapsed Childhood Acute Lymphoblastic Leukemia Presenting As an Isolated Breast Mass.
    Date October 1999
    Journal Clinical Pediatrics
    Title Epstein-barr Virus Polymerase Chain Reaction and Serology in Pediatric Post-transplant Lymphoproliferative Disorder: Three-year Experience.
    Date August 1999
    Journal Pediatric and Developmental Pathology : the Official Journal of the Society for Pediatric Pathology and the Paediatric Pathology Society
    Excerpt

    To assess whether the semiquantitative peripheral blood Epstein-Barr virus (EBV) polymerase chain reaction (PCR) test correlates with post-transplant lymphoproliferative disorder (LPD), we compiled the results of the test done over a 3-year period ending July 1997. Six hundred seventy-six tests were done on 185 patients. Four hundred-thirty tests (63%) were negative, 167 (25%) were weak positive, 67 (10%) were moderate positive, and 12 (2%) were strong positive. Twelve of the patients developed a lymphoproliferative disorder (LPD) during this time. The EBV PCR tests proximate to the diagnosis of LPD in the 12 patients with EBV-positive LPD were 6 strong positive, 5 moderate positive, 1 weak positive. No patient with LPD had a negative result at diagnosis. Stated another way, 6/12 (50%) of strong-positive PCR tests, 5/67 (7%) moderate-positive tests, and 1/167 (.6%) of weak-positive tests correlated with LPD. Serologic evaluation for EBV done on 7 patients at the time of LPD showed low serologic responses in 5 of the 7 patients. The EBV PCR temporally associated with the serology indicated moderate to large viral burdens. In each patient evaluated serially, the EBV PCR test rose before the diagnosis of LPD and fell with treatment for the disorder. In conclusion, the EBV PCR test may be used as an adjunct to the diagnosis of patients with LPD and may be used to monitor response to therapy for the disorder.

    Title Case Report of a 22-week Fetus with 47,xxx Karyotype and Multiple Lower Mesodermal Defects.
    Date March 1999
    Journal Pediatric and Developmental Pathology : the Official Journal of the Society for Pediatric Pathology and the Paediatric Pathology Society
    Excerpt

    A 22-week stillborn fetus with 47,XXX karyotype had lower mesodermal defects consisting of irregular fusion of the sacral vertebrae, anal agenesis, multicystic dysplasia of a horseshoe kidney, a single umbilical artery, dysplastic ovaries, and uterine hypoplasia. This case provides additional evidence for an association between trisomy X and genitourinary defects including lower mesodermal defects sequence.

    Title Expression of the Rna Component of Telomerase in Wilms Tumor and Nephrogenic Rest Recapitulates Renal Embryogenesis.
    Date June 1998
    Journal Human Pathology
    Excerpt

    Telomerase is a ribonucleoprotein enzyme associated with cellular immortality and has been detected in the vast majority of adult tumors. Wilms tumor is a histologically diverse embryonal malignancy of childhood, and the histological features of Wilms tumor and its precursor lesion, the nephrogenic rest, recapitulate the components of normal renal embryogenesis. Both the epithelial and the stromal components of Wilms tumor arise by differentiation of primitive mesodermal blastema. We compared expression of the RNA component of human telomerase (hTR) in normal developing kidneys, Wilms tumors, and nephrogenic rests and correlated expression of hTR with cell proliferation. Using a radioactive in situ hybridization method, we examined archival material from 17 Wilms tumors (including nine with nephrogenic rests), four therapeutically aborted embryos (37 to 56 days), three fetuses on whom autopsies had been performed, and one neonate for expression of hTR. Proliferative index was measured by immunohistochemical staining for MIB1. In the embryonic kidney, Wilms tumors, and nephrogenic rests, the patterns of hTR expression were similar: expression was usually maximal within the immature epithelial elements followed by the poorly differentiated blastema, but was weak or absent in the immature stroma. Mature tubules, glomeruli, and stroma were negative for hTR expression, as were differentiated heterologous elements present in post-therapy Wilms tumors. There was only a partial relationship between proliferative index and hTR expression. In the embryonic kidney, Wilms tumors, and nephrogenic rests, blastema had the highest proliferative index, whereas the indices were significantly lower in the immature epithelium and stroma. The proliferative index in mature and heterologous elements was low or zero. Thus, the pattern of hTR expression in Wilms tumor and its precursor lesion recapitulates embryogenesis precisely and may represent that aspect of the persistent fetal phenotype which predisposes to the development of malignancy.

    Title Clinical, Biochemical, and Morphologic Investigations of a Case of Long-chain 3-hydroxyacyl-coa Dehydrogenase Deficiency.
    Date August 1997
    Journal Archives of Pathology & Laboratory Medicine
    Excerpt

    We report the premortem and postmortem morphologic and histologic features and biochemical findings of a patient with long-chain 3-hydroxyacyl-CoA dehydrogenase (L-CHAD) deficiency and compare these with those described in previously reported cases of L-CHAD deficiency. In addition to chronic nonketotic hypoglycemia, hypotonia, and liver failure, this patient had chronic hemolytic anemia and delayed central nervous system myelination. These features have not been previously documented in L-CHAD deficiency.

    Title Epstein-barr Virus Pcr Correlated with Viral Histology and Serology in Pediatric Liver Transplant Patients.
    Date August 1997
    Journal Pediatric Pathology & Laboratory Medicine : Journal of the Society for Pediatric Pathology, Affiliated with the International Paediatric Pathology Association
    Excerpt

    Epstein-Barr virus (EBV)-associated illnesses in posttransplant patients are difficult to diagnose. Attempts to aid in the diagnosis of such illnesses using the polymerase chain reaction (PCR) analysis for EBV have met with variable success due to the potential exquisite sensitivity of the assay. We have designed a relatively insensitive EBV PCR assay and compared the results with objective evidence of EBV activity including serologic response and in situ hybridization for the EBV genome. Eighty-five specimens from 65 patients were analyzed by the EBV PCR using DNA from whole blood. EBV serologic evaluation was done on 53 of the samples and in situ hybridization for EBV (EBER-1 mRNA) on 46 paired liver biopsies. Of 85 samples, 25 (29%) were positive for EBV using the PCR assay. Intensity of amplification was graded 0.5-1+ (weak) to 3+ (strong). Using these criteria, 19 EBV PCR-positive samples were graded 0.5-1+, 5 were graded 2+, and 1 was graded 3+. Of the moderate to strongly positive samples (2+ or 3+), five of six had two or more EBER-1-positive cells in the liver biopsies. Of the remaining 40 liver biopsies with either negative or weak positive PCR results, 3 had only single cells positive for EBER-1; the remainder were negative. In addition, PCR-positive results correlated with increasing EBV anti-early antigen antibody (P = .005) and viral capsid antigen IgG immunoglobulin G VCA (P = .05) EBV-positive results using the PCR assay correlated with objective evidence for increased EBV burden in children after liver transplantation. These preliminary data suggest that this PCR test may be useful to help guide immunosuppressive therapy in the posttransplant patient. Further evaluation using larger numbers of patients will be necessary to confirm this.

    Title Pseudomelanosis Duodeni in an Adolescent Male: Case Report and Review of the Literature.
    Date May 1997
    Journal Pediatric Pathology & Laboratory Medicine : Journal of the Society for Pediatric Pathology, Affiliated with the International Paediatric Pathology Association
    Excerpt

    Pseudomelanosis duodeni is rarely seen in children. It manifests endoscopically as peppery speckles in the duodenal mucosa. This pigment corresponds principally to accumulation of ferrous sulfide in macrophages within the lamina propria. We report the case of a 16-year-old boy with ectodermal dysplasia who underwent renal transplantation for vesicoureteral reflux and later developed epigastric pain. Endoscopic and pathologic findings in the duodenal mucosa were typical of pseudomelanosis duodeni. A review of the literature reveals shared clinical features among reported adult and pediatric cases, including chronic renal failure, use of antihypertensive medication and oral iron supplementation, and/or presence of gastric hemorrhage.

    Title Recognition and Treatment of Venous Malformations of the Rectum.
    Date March 1997
    Journal Journal of Pediatric Gastroenterology and Nutrition
    Excerpt

    Venous malformations of the rectum are uncommon lesions that present complex management problems (1-6). The vast majority of these lesions present with rectal bleeding in infancy or childhood. Many cases have been treated as colitis for years before the correct diagnosis was made. The correct diagnosis has generally been based on gross appearance, confirmed subsequently by plain radiographs and angiography. Heroic surgical intervention has been the only repeatedly reported "cure" in the literature. One patient has been reported who did well for 20 years with sclerosis of the hemorrhoidal vein at surgery followed by intermittent transrectal sclerotherapy (7,8). Another patient would appear to have had longterm success with radiation therapy (9-11). We report four new cases of venous malformations of the rectum and results to date of a new therapeutic option with transcutaneous ethanol sclerotherapy in two of these patients. A discussion of alternate methods of treatment is included.

    Title Polymerase Chain Reaction Amplification of Archival Material for Parvovirus B19 in Children with Transient Erythroblastopenia of Childhood.
    Date March 1997
    Journal Pediatric Pathology & Laboratory Medicine : Journal of the Society for Pediatric Pathology, Affiliated with the International Paediatric Pathology Association
    Excerpt

    The relationship between transient erythroblastopenia of childhood (TEC) and parvovirus B19 infection remains uncertain. Large series using primarily serologic evaluation have not shown an association, whereas smaller series have reported parvovirus B19 infection in such patients. Further, parvovirus DNA or antigen has been detected in some patients seronegative for the virus at presentation. Polymerase chain reaction (PCR) amplification has never been used to evaluate patients with TEC for parvovirus B19. We used the PCR in an attempt to detect parvovirus B19 in DNA extracted from archived bone marrow coverslips of 16 patients diagnosed with TEC. The patients ranged in age from 3 to 23 months and presented with a mean hemoglobin value of 5.4 g/dL. Sixty-nine percent were neutropenic and none was thrombocytopenic. None of the patients had histologic evidence of parvovirus B19 infection in the bone marrow. DNA amplification for parvovirus B19 was negative in each case. In contrast, parvovirus B19DNA was amplified from DNA isolated from archived bone marrow coverslips of a patient with known parvovirus B19 infection, indicating that the PCR assay was sufficiently sensitive to detect virus from archieved bone marrow coverslips. Review of the literature indicates that the patients with parvovirus-associated TEC are generally older and often present with concomitant thrombocytopenia, whereas patients with parvovirus B19-negative TEC are younger and present without thrombocytopenia, similar to the patients in our study. Our results suggest that parvovirus B19 is not the cause of anemia in the young patient with typical features of TEC. Rather, parvovirus B19 infection of older, previously healthy children may occasionally cause a protracted anemia, often with thrombocytopenia, which may be diagnosed by some as TEC.

    Title Focal Dermal Hypoplasia (goltz Syndrome) with Vertebral Solid Aneurysmal Bone Cyst Variant. A Case Report.
    Date February 1997
    Journal Pediatric Neurosurgery
    Excerpt

    Focal dermal hypoplasia or Goltz syndrome is a rare clinical entity, usually presenting in early childhood as a mix of ectodermal and mesodermal anomalies. Previously reported cases have included skeletal lesions of the long bones, metacarpals, metatarsals and pelvis. We present a case with a vertebral lesion causing neurologic deficit. A discussion of the history of the syndrome is included as well as detailed histologic description.

    Title Interferon-alpha-2b Treatment of Chronic Hepatitis C in Children with Hemophilia.
    Date January 1997
    Journal The Pediatric Infectious Disease Journal
    Title Report of a Complex Karyotype in Recurrent Metastatic Fibrolamellar Hepatocellular Carcinoma and a Review of Hepatocellular Carcinoma Cytogenetics.
    Date July 1996
    Journal Cancer Genetics and Cytogenetics
    Excerpt

    Metastatic fibrolamellar hepatocellular carcinoma (HCC) was detected in the abdominal lymph nodes of an adolescent male after resection of the primary tumor. No dividing cells were isolated from attempted cytogenetic studies of the primary tumor. However, cytogenetic analysis of lymph node metastases detected 9 and 12 months after partial hepatectomy revealed abnormal hypertriploid karyotypes, with a suggestion of clonal evolution: 62-92 < 3n >,XX, -Y, +3, +6, +6, +7, +7, +8, +10, +13, +15, +16, +20, -21, -22, +mar1 x 2, +mar[cp6]/46,XY[8] and 78 < 3n >,XX, -Y,der(1)t(1;1)(p36.1;q21), +4, +6, +6, +7, +7,i(8)(q10), +10, +15, +20, -21, -22, +mar1 x 2, +mar2[3]/46, XY[17], respectively. Karyotypes of this variant of HCC have not been reported previously. The cytogenetics of HCC are reviewed.

    Title Epstein-barr Virus-associated Leiomyosarcomas in Liver Transplantation Recipients. Origin from Either Donor or Recipient Tissue.
    Date June 1996
    Journal Cancer
    Excerpt

    BACKGROUND. Leiomyosarcoma, a mesenchymal malignancy with smooth muscle differentiation, is extremely rare in children. Immunosuppression, due to either antirejection medication in organ transplantation recipients or human immunodeficiency virus infection (HIV), appears to constitute a predisposition. METHODS. Two cases of leiomyosarcoma in pediatric liver transplantation recipients were investigated and compared clinically with respect to site of origin and course of the disease and pathologically by routine histology and electron microscopy, by forensic DNA methodology for origin from donor or recipient tissue, and by EBER-1 in situ hybridization for evidence of latent Epstein-Barr virus (EBV) infection. RESULTS. A 9-year-old male developed a high grade, poorly differentiated leiomyosarcoma in his allografted liver 2 years after transplantation, and despite antineoplastic chemotherapy, he died of metastatic disease. The genotype of his tumor indicated an origin from allografted tissue. A 12-year-old female had a low grade retroperitoneal leiomyosarcoma involving the superior mesenteric vein. After resection, she remained disease free without chemotherapy. The genotype of her tumor indicated an origin from native tissue. In both tumors, latent EBV infection was documented. CONCLUSIONS. Neoplastic smooth muscle proliferation in immunosuppressed liver transplantation recipients is analogous to the more common posttransplantation lymphoproliferative disorder in involving transformation of either engrafted donor tissue or recipient tissue elsewhere in the body, in displaying a wide spectrum of histologic differentiation, grade and clinical behavior, and in exhibiting evidence of latent EBV infection.

    Title Relapse of Precursor B-cell Acute Lymphoblastic Leukemia As an Isolated Central Nervous System Mass Lesion 9 Years After Initial Diagnosis.
    Date January 1996
    Journal Medical and Pediatric Oncology
    Excerpt

    Seven years after completion of chemotherapy for acute lymphoblastic leukemia, diagnosed at the age of 5 years, a black female presented with signs of increased intracranial pressure. Neuroimaging showed a large enhancing extra-axial occipital tumor mass. The resection specimen showed morphologic, cytogenetic, and immunophenotypic features consistent with relapse of the primary leukemia. Bone marrow examination was negative for malignancy. The long duration of complete remission followed by the formation of a mass in the central nervous system are highly unusual features of recurrent acute lymphoblastic leukemia.

    Title Does Activation of the Tal1 Gene Occur in a Majority of Patients with T-cell Acute Lymphoblastic Leukemia? A Pediatric Oncology Group Study.
    Date August 1995
    Journal Blood
    Excerpt

    Almost 25% of patients with T-cell acute lymphoblastic leukemia (T-ALL) have tumor-specific rearrangements of the TAL1 gene. Although TAL1 expression has not been observed in normal lymphocytes, TAL1 gene products are readily detected in leukemic cells that harbor a rearranged TAL1 allele. Hence, it has been proposed that ectopic expression of TAL1 promotes the development of T-ALL. In this report, we show that TAL1 is expressed in the leukemic cells of most patients with T-ALL, including many that do not display an apparent TAL1 gene alteration. A polymorphic dinucleotide repeat in the transcribed sequences of TAL1 was used to determine the allele specificity of TAL1 transcription in primary T-ALL cells. Monoallelic expression of TAL1 was observed in the leukemic cells of all patients (8 of 8) bearing a TAL1 gene rearrangement. In the leukemic cells of patients without detectable TAL1 rearrangements, TAL1 transcription occurred in either a monoallelic (3 of 7 patients) or a biallelic (4 of 7 patients) fashion. Thus, TAL1 activation in these patients may result from subtle alterations in cis-acting regulatory sequences (affecting expression of a single TAL1 allele) or changes in trans-acting factors that control TAL1 transcription (affecting expression of both TAL1 alleles).

    Title Renal Cell Carcinoma with Translocation (x;1). Further Evidence for a Cytogenetically Defined Subtype.
    Date July 1995
    Journal Cancer Genetics and Cytogenetics
    Excerpt

    A renal cell carcinoma from a 15-year-old male had a 49,Y,t(X;1)(p11.2;q21), +der(X)t(X;1) (p11.2;q21), +5, -16, +17, +18 karyotype. This is the third report of a translocation involving a breakpoint at Xp11.2 in a renal cell carcinoma in a child. A total of nine cases of renal cell carcinoma involving Xp11, including this case, have been reported. Of the eight cases for which there are genetics reports, all are male. Patients with renal cell carcinoma with abnormalities at Xp11 appear to be younger than renal cell carcinoma patients overall.

    Title Chromosomal Instability in Hereditary Tyrosinemia Type I.
    Date March 1995
    Journal Pediatric Pathology / Affiliated with the International Paediatric Pathology Association
    Title Rhabdoid Tumor of the Kidney with Primitive Neuroectodermal Tumor of the Central Nervous System: Associated Tumors with Different Histologic, Cytogenetic, and Molecular Findings.
    Date February 1995
    Journal Genes, Chromosomes & Cancer
    Excerpt

    Rhabdoid tumor of the kidney (RTK) is associated with tumors of the central nervous system (CNS) in approximately 15% of cases. We describe the clinical features, histologic and cytogenetic findings, and molecular analysis of renal and CNS tumors from the same patient. The histology of the renal tumor was consistent with rhabdoid tumor. The CNS tumor was a primitive neuroectodermal tumor (PNET). The karyotype of the RTK was normal male. The PNET of the brain demonstrated monosomy 22 as the only cytogenetic abnormality, similar to reported cases of malignant rhabdoid tumor of the brain, but dissimilar to nonrandom cytogenetic findings in other CNS PNETs. Molecular cytogenetic and DNA marker studies confirmed loss of chromosome 22 in this patient's brain tumor. DNA allelotyping showed retention of both parental chromosome 22 alleles in the RTK and loss of the maternal allele in the PNET. Evaluation of additional RTKs and brain tumors occurring in the same patient may provide insight into the origins and relationships of these enigmatic tumors.

    Title Trisomy 2, Trisomy 20, and Del(17p) As Sole Chromosomal Abnormalities in Three Cases of Hepatoblastoma.
    Date February 1995
    Journal Genes, Chromosomes & Cancer
    Excerpt

    Short-term cultures of three hepatoblastomas were analyzed cytogenetically. Trisomy 2, trisomy 20, and a deletion of 17p were found as the sole abnormalities, yielding the karyotypes 47,XY, + 2; 47,XX, + 20; and 46,XX,del(17)(p12)/46,XX. This is the first reported case of deletion of 17p as the sole chromosomal abnormality in a hepatoblastoma and the first reported case of trisomy 20 without double minute chromosomes as a sole chromosomal abnormality in hepatoblastoma.

    Title Potentiation of Acetaminophen Hepatotoxicity in a Child with Mercury Poisoning.
    Date February 1995
    Journal Journal of Pediatric Gastroenterology and Nutrition
    Title Acute Basophilic Leukemia in a Child. Anaphylactoid Reaction and Coagulopathy Secondary to Vincristine-mediated Degranulation.
    Date January 1995
    Journal Cancer
    Excerpt

    BACKGROUND. Acute de novo basophilic leukemia (ABL) is uncommon in adults, and extremely rare in children. To the authors' knowledge, there have been no previous reports of anaphylactoid reactions from basophilic degranulation in children with this condition. METHODS. This report describes the clinicopathologic profile and complications of a patient with de novo ABL. RESULTS. Immediately after the first induction dose of intravenous vincristine, the patient developed an anaphylactoid reaction and disseminated intravascular coagulation with massive pulmonary hemorrhage. A normal serum tryptase level suggested that this life-threatening event was secondary to tumor lysis (basophilic degranulation), rather than to a mast-cell mediated anaphylactic reaction to vincristine. This interpretation is supported by the coagulation studies, which suggested release of heparin from the blast granules. CONCLUSIONS. Although de novo ABL is rare, it should be considered when cytoplasmic basophilic granules are seen in the leukemic cells of patients with what otherwise appears to be undifferentiated leukemia, and the pertinent diagnostic procedures should be undertaken. During the treatment of ABL, potential complications related to basophilic degranulation should be anticipated, and antihistamine prophylaxis may be of value.

    Title Subacute Measles Encephalitis in the Young Immunocompromised Host: Report of Two Cases Diagnosed by Polymerase Chain Reaction and Treated with Ribavirin and Review of the Literature.
    Date July 1993
    Journal Clinical Infectious Diseases : an Official Publication of the Infectious Diseases Society of America
    Excerpt

    Two young patients with subacute measles encephalitis are described: a 20-year-old male hemophiliac infected with human immunodeficiency virus (HIV) and a 4-year-old girl with acute leukemia. Both patients were afebrile and had persistent focal seizures and slurred speech beginning 2 and 7 months, respectively, after the onset of uncomplicated acute measles. The diagnosis of subacute measles encephalitis was established by demonstration of paramyxovirus nucleocapsid on electron microscopy of brain tissue in one case and by detection of measles virus genome with the polymerase chain reaction in both. Treatment of the HIV-infected man with intravenous ribavirin was begun when the patient lost consciousness after several weeks of seizures; he died. The girl with leukemia was treated early after the onset of symptoms and recovered after a 15-week course. Review of 31 previously published cases revealed a typical clinical presentation. Cerebrospinal fluid (CSF) analysis, electroencephalography, measurement of measles antibody in serum and CSF, and computed tomography of the brain were not helpful in the diagnosis of subacute measles encephalitis. In contrast, histologic examination of brain tissue proved useful in establishing the diagnosis. On the basis of our experience and our literature review, we conclude that histologic and polymerase chain reaction studies of brain tissue are required for the early diagnosis of subacute measles encephalitis and that therapy with intravenous ribavirin is effective when administered early.

    Title Rhabdomyomatous Mesenchymal Hamartoma of Skin.
    Date December 1992
    Journal Pediatric Pathology / Affiliated with the International Paediatric Pathology Association
    Excerpt

    A distinctive dermal and subcutaneous hamartoma composed primarily of disorganized skeletal muscle and mature adipose tissue, designated rhabdomyomatous mesenchymal hamartoma of skin, was recently reported. We have observed two histologically similar though less polypoid lesions in boys aged 4 years. Both were also on the chin and present since birth, suggesting that site and age, as well as histology, may be characteristic. The location on the chin in three of the four neonates may reflect an etiology of aberrant embryologic development of the platysma muscle as it inserts superficially into the dermis over the mandible.

    Title Childhood Acute Lymphoblastic Leukemia with Both T(1;19) and T(9;22).
    Date July 1992
    Journal Leukemia : Official Journal of the Leukemia Society of America, Leukemia Research Fund, U.k
    Excerpt

    The chromosomal rearrangements t(1;19)(q23;p13.3) and t(9;22) (q34;q11.2) are independent abnormalities commonly observed in the blast cells of children with acute lymphoblastic leukemia (ALL). We report three children whose leukemic cells contained both translocations at diagnosis. The patients, two males aged 3 and 8 years and a female aged 14 years, all presented with central nervous system involvement. One patient exhibited a pre-B leukemic phenotype (cytoplasmic immunoglobulin, cIg, positive), while two had an early pre-B phenotype (cIg negative). All three patients received radiotherapy and multiagent chemotherapy which included an epipodophyllotoxin in two patients. Two patients suffered relapses of ALL, in both cases with disappearance of t(1;19)-containing clones but persistence of t(9;22). The two patients who received an epipodophyllotoxin as part of their chemotherapeutic regimen both developed secondary myeloid leukemia with entirely new cytogenetic findings, including abnormalities of chromosome band 11q23. These patients are the first to be described with this unusual combination of cytogenetic abnormalities.

    Title Rna Expression of the Wt1 Gene in Wilms' Tumors in Relation to Histology.
    Date April 1992
    Journal Journal of the National Cancer Institute
    Excerpt

    BACKGROUND: On the basis of accumulating data, the recently isolated WT1 gene is a Wilms' tumor gene and a putative tumor suppressor gene. These findings include expression in developing fetal kidney, intragenic deletions in tumors, and germline mutations in predisposed individuals. Wilms' tumors, which exhibit a broad range of differentiation, are composed of three cell types: blastema, epithelium, and stroma. PURPOSE: The purpose of this study was to investigate the relationship between WT1 gene expression and histologic composition in Wilms' tumors in an effort to elucidate how the WT1 gene functions in proliferation of these histologic components. METHODS: We used Northern blot hybridization to study WT1 gene expression by messenger RNA (mRNA) accumulation in 20 tumors of varying histology and in adjacent uninvolved kidney tissue. In two patients, tumors were also compared before and after therapy. RESULTS: Tumors that were predominantly blastemal expressed high amounts of WT1 mRNA, whereas predominantly stromal tumors expressed either low or undetectable amounts. Blastemal tumors that were predominantly poorly differentiated expressed WT1 mRNA at higher levels than those that were more well differentiated. Although we expected that a putative tumor suppressor gene like WT1 would generally be expressed at lower levels in tumor than in normal kidney, this was true only in predominantly stromal cells. One of the two patients studied before and after therapy had a dramatic response to therapy accompanied by a decline in WT1 gene expression and disappearance of blastemal and epithelial elements. CONCLUSIONS: A correlation was observed between WT1 gene expression and histology of the tumors. Level of expression was inversely related to the degree of differentiation in blastemal tumors and in the patient with a dramatic response to therapy. These results, in conjunction with the observation that WT1 mRNA is abundant in normal fetal kidney, suggest that WT1 gene expression is related to kidney development, especially in differentiation of blastemal components. IMPLICATIONS: Further studies to search for alterations of the WT1 gene in tumors and to identify regulatory factors in gene expression will increase understanding of the role of this gene in normal development and tumorigenesis.

    Title Xanthomatous Pseudotumor of the Small Intestine Following Treatment for Burkitt's Lymphoma.
    Date March 1992
    Journal Archives of Pathology & Laboratory Medicine
    Excerpt

    A 9-year-old boy with a large mass in the right lower quadrant of the abdomen was diagnosed as having disseminated Burkitt's lymphoma by pleural fluid aspirate. After 4 months of chemotherapy, he developed acute small-bowel obstruction. A resected ileal segment contained a bright-yellow annular submucosal tumor, histologically a xanthoma, that infiltrated the muscularis propria and serosa. No residual lymphoma was identified. We believe that the small-bowel xanthoma in this child is an unusual, nonneoplastic, treatment-related sequela of lymphoma cell lysis and histiocytic scavenging of lipid-membranous debris.

    Title Cytogenetics of a Renal Cell Carcinoma in a 17-month-old Child. Evidence for Xp11.2 As a Recurring Breakpoint.
    Date February 1992
    Journal Cancer Genetics and Cytogenetics
    Excerpt

    A renal cell carcinoma from a 17-month-old boy with a history of maternal hydrocarbon exposure was found to have a 46,Y,t(X;17)(p11.2;q25) karyotype. Although this translocation has not previously been reported, other translocations involving Xp11.2 have been described, suggesting that this may represent a non-random breakpoint involved in the pathogenesis of childhood renal cell carcinoma. Both chromosomes 3 in the tumor were normal by both karyotype and RFLP analysis.

    Title Chronic Human Parvovirus B19-induced Erythroid Hypoplasia As the Initial Manifestation of Human Immunodeficiency Virus Infection.
    Date July 1991
    Journal The Journal of Pediatrics
    Title Hyperdiploidy Including Trisomy 8 in a Cystic Partially Differentiated Nephroblastoma.
    Date October 1989
    Journal Cancer Genetics and Cytogenetics
    Excerpt

    Cystic partially differentiated nephroblastoma (CPDN), a rare, cystic, renal lesion of childhood, has not been previously karyotyped. It is distinguished histologically from multilocular renal cyst by the presence of blastemal cells, and from Wilms' tumor by lack of expansile, solid growth and by indolent clinical behavior. In the present case, ten of 20 analyzed cells from a 3-week culture obtained from the tumor had a clonal, hyperdiploid karyotype. The modal chromosome number was 51, with chromosomes 8, 12, 17, 19, and 20 usually being present in three copies. Trisomy 8 was present in every hyperdiploid cell examined. A normal 46,XY constitutional karyotype was also observed. In degree and significance, the hyperdiploidy of CPDN is thus distinct from that reported in the prognostically unfavorable, anaplastic Wilms' tumor, where the DNA index is typically near-tetraploid. Trisomy 8, as a constitutional mosaicism, has been previously reported in children with bilateral CPDN and/or undifferentiated sarcomas, although none of their tumors were karyotyped. The present findings support a neoplastic nature for CPDN, while emphasizing its pathogenetic distinctiveness from Wilms' tumor, and provide further evidence for significance of trisomy 8 in the pathobiology of this tumor.

    Title Primary Cerebral Neuroblastoma.
    Date July 1989
    Journal Ultrastructural Pathology

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