Dr. Rena D. Callahan, MD | Santa Monica, CA | Oncologist

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Dr. Rena Callahan is a board-certified oncologist and internal medicine physician who graduated from the prestigious Perelman School of Medicine at the University of Pennsylvania. With 22 years of experience treating cancer patients, she has built expertise in comprehensive oncology care with a particular focus on breast cancer treatment. Dr. Callahan is fluent in both English and Spanish, allowing her to serve diverse patient populations throughout the Los Angeles area.

She practices at multiple UCLA Medical Group locations across Santa Monica, Valencia, and Los Angeles, with hospital affiliations including Huntington Memorial Hospital. Dr. Callahan specializes in treating breast cancer, including complex metastatic and recurrent cases, as well as rare conditions like Paget disease of the breast. Her treatment approach includes advanced infusion therapy and comprehensive blood monitoring through complete blood counts and specialized testing. Patients have given Dr. Callahan an …average rating of 4.5 stars, reflecting their confidence in her compassionate and expert care.

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Overview based on verified provider data

accepting new patients
4.5

24 Ratings
22 years of experience
43 insurance plans accepted
speaks English, Spanish
Perelman School Of Medicine At University Of Pennsylvania
12 written reviews
2 specialties
26 areas of expertise
2 board certifications
1 hospital affiliation
7 office locations
Female

Gave an accurate diagnosis
Had a good bedside manner
Spent time with me

Based on patient feedback. Read the reviews

Dr. Callahan's Ratings and Reviews

4.5

24 Ratings with 12 written Reviews

Average Wait Time 9 Minutes

How was your appointment with
Dr. Callahan?

Patients’ Perspective

Gave an accurate diagnosis: (14) Did WellNeeds Improvement (0)
Had a good bedside manner: (14) Did WellNeeds Improvement (0)
Spent time with me: (15) Did WellNeeds Improvement (0)
Provided follow-up after the visit: (15) Did WellNeeds Improvement (0)
Flexible scheduling: (15) Did WellNeeds Improvement (0)
Saw me in a timely manner: No Ratings
Staff was courteous: No Ratings

24 ratings & reviews

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Showing 1 to 10 of 12 reviews

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I would give Dr. Callahan a thousand stars if I could. She is a stand out. I haven't had many great experiences with doctors before meeting Dr. Callahan. I trust her with my life.

March 27th, 2022

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She saved my life!! Can I say more? I really couldn't be happier with the care provided by Dr. Callahan and her staff.

September 6th, 2019

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She is smart, funny, patient, empathetic and all around a wonderful doctor Her bedside manner is great - she listens and is direct and specific in her answers, and she is very kind. believe me if you get a cancer diagnosis, this is the doctor you want heading your team

December 17th, 2018

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I absolutely LOVE Dr. Callahan. She makes you feel comfortable and cares about your situation. She is very knowledgeable. I saw 5 other Oncologist in addition to Dr. Callahan and she is my Favorite! She did not recommend the harsh chemo therapy protocols that I was told I needed by other Oncologists, especially the dose densing (standard protocol). I trust this Doctor and I can't thank her enough for all she does. Her education and background explains what type of person she is... Very professional and SMART!

June 9th, 2016

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Amazing bedside manner coupled with smarts.

September 25th, 2015

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Clinical expertise combined with tremendous compassion - a winning combination. She responds quickly to phone calls and emails.

July 13th, 2015

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I can't say enough good things about Dr. Callahan. She listened to me (even through my tears) like no other doctor I've ever met. I can communicate with her via email (she's very quick to respond). And, she is incredibly smart. The complete package. If you are not happy with your oncologist go to her. I'm so so glad I did.

January 8th, 2015

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I was on my third oncologist and Dr. callahan was the fisrt one who actually took the time to listen to my concerns. She is thorough, thoughtful, and intelligent.

May 3rd, 2013

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I can't say enough good things about Dr. Callahan. She's a brilliant oncologist and a warm, caring person. The best of both worlds!

September 28th, 2011

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Rena is just great (and you can call her by her 1st name!). I had been through some other docs who just didn't know how to listen. She is young and super smart. highly recommend.

February 7th, 2011

Ucla Santa Monica Parkside

2336 Santa Monica Blvd Ste 304Santa Monica, CA 90404

Tel: (310) 998-4747

UCLA Medical Group

23929 McBean Pkwy Ste 215Valencia, CA 91355

Tel: (661) 255-5350

Mon8:00 am - 5:00 pm

Tue8:00 am - 5:00 pm

Wed8:00 am - 5:00 pm

Thu8:00 am - 5:00 pm

Fri8:00 am - 5:00 pm

SatClosed

SunClosed

Dr. Rena Desai Callahan

10945 Le Conte AveLos Angeles, CA 90095

Ucla Medical Center

200 UCLA Medical PlzLos Angeles, CA 90095

Tel: (661) 255-5350

Dr. Rena Desai Callahan

2336 Santa Monica BlvdSanta Monica, CA 90404

Santa Monica Ucla Medical Center And Orthopaedic Hospital

1250 16th StSanta Monica, CA 90404

Henry Mayo Newhall Memorial Hospital

23845 Mcbean PkwyValencia, CA 91355


Dr. Rena Desai Callahan, MD	Dr. Shahrooz Eshaghian, MD, FACP	Dr. Ronald Tang, DO	Dr. Virginia Von Schaefer, MD
Oncology	Oncology	Oncology	Oncology
Accepts New Patients	Accepts New Patients	Accepts New Patients	Accepts New Patients
4.5 (24 Ratings)	4.6 (28 Ratings)	5 (6 Ratings)	4 (4 Ratings)
22 Years of Experience	20 Years of Experience	18 Years of Experience	43 Years of Experience
No Virtual Visit Option	No Virtual Visit Option	No Virtual Visit Option	Virtual Visit Available
Speaks English, Spanish	Speaks English, Farsi, Hebrew	Speaks English, Cantonese, Spanish	Speaks English
Santa Monica , CA	Los Angeles , CA	Montebello , CA	San Clemente , CA
Med School: Perelman School Of Medicine At University Of Pennsylvania	Med School: Albert Einstein College of Medicine	Med School: Western Univ Health Sci College Of Osteopathic Medicine Of The Pacific	Med School: Columbia University College Of Physicians & Surgeons
Current Profile	View Profile	View Profile	View Profile

Search for your insurance and plan

Acute Myeloid Leukemia
Blood Cancer
Bone Marrow Transplant
Breast Cancer
Cancer
Chemotherapy
Chronic Myeloid Leukemia
Deep Vein Thrombosis
Head and Neck Cancer
Hepatitis C
Internal Medicine
Leukemia
Liver Cancer
Lung Cancer
Lymphoma
Melanoma
Metastatic Breast Cancer
Multiple Myeloma (Cancer of Plasma Cells)
Myelofibrosis
Myeloma
Palliative Care
Pancreatic Cancer
Prostate Cancer (Prostatic Neoplasm)
Sickle Cell Anemia
Thoracic Cancer
Uterine Cancer

Education & Training

Medical School

Graduated from Perelman School Of Medicine At University Of Pennsylvania in 2004.

NPI Number

Dr. Callahan's NPI number is 1487856779.

Dr. Myron Tzalel Berdischewsky, MD
Infectious Disease
52 Years Exp | Studio City, CA
(0)
Dr. K Joan Wareham Flacke
Anesthesiology
67 Years Exp | Los Angeles, CA
(0)
Dr. Masataka Gunshin
Emergency Medicine
31 Years Exp | Los Angeles, CA
(0)
Dr. Sith Sathornsumetee
Nephrology
28 Years Exp | LOS ANGELES, CA
(0)
Dr. Andres Ricardo Wurgaft
Nephrology
38 Years Exp | LOS ANGELES, CA
(0)
Dr. Padideh Pourmorad
Critical Care Medicine
30 Years Exp | Torrance, CA
(0)
Dr. Ching-Piao Chien
Psychiatry
67 Years Exp | Los Angeles, CA
(0)
Dr. Harlan Keith Bixby
Nephrology
57 Years Exp | Arcadia, CA
(1)
Dr. Ellen D Bolotin
Pediatrics
50 Years Exp | Duarte, CA
(0)
Dr. Charles Frank Farthing
Infectious Disease
50 Years Exp | West Hollywood, CA
(0)

Where is Dr. Rena Callahan's office located?: Dr. Rena Callahan's office is located at 2336 Santa Monica Blvd Ste 304, Santa Monica, CA, 90404.
Is Dr. Rena Callahan accepting new patients?: Dr. Rena Callahan is accepting new patients on Vitals. View Dr. Rena Callahan's profile on Vitals to make an appointment.
What languages does Dr. Rena Callahan speak?: Dr. Rena Callahan speaks English and Spanish.
Does Dr. Rena Callahan accept my insurance?: You can see the insurance plans that Dr. Rena Callahan accepts on their Vitals profile.
Which hospitals is Dr. Rena Callahan affiliated with?: Dr. Rena Callahan is affiliated with Huntington Memorial Hospital.

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