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Hematologists and Oncologists in California

Data updated monthly · Last refresh October 2026

1,582 Hematology & Oncology providers practice in California, including 855 (54%) offering telehealth. The largest concentration is in Los Angeles. Profiles include federal Open Payments records of money received from drug and device companies in 2025. Listings are drawn from federal public records and are not endorsements.

1,582providers
855telehealth
Los Angelestop city

Hematology & Oncology by city in California

Choose a city to see providers there.

Hematology & Oncology in Los Angeles152 providers
Hematology & Oncology in San Diego89 providers
Hematology & Oncology in Sacramento77 providers
Hematology & Oncology in San Francisco64 providers
Hematology & Oncology in Orange62 providers
Hematology & Oncology in La Jolla46 providers
Hematology & Oncology in Santa Monica43 providers
Hematology & Oncology in Torrance33 providers
Hematology & Oncology in Fresno31 providers
Hematology & Oncology in Stanford30 providers
Hematology & Oncology in Walnut Creek23 providers
Hematology & Oncology in Newport Beach21 providers
Hematology & Oncology in Rancho Mirage19 providers
Hematology & Oncology in Long Beach18 providers
Hematology & Oncology in Roseville17 providers
Hematology & Oncology in Fountain Valley17 providers
Hematology & Oncology in Beverly Hills16 providers
Hematology & Oncology in Santa Barbara16 providers
Hematology & Oncology in San Jose15 providers
Hematology & Oncology in Oakland14 providers
Hematology & Oncology in Downey14 providers
Hematology & Oncology in Anaheim14 providers
Hematology & Oncology in Irvine13 providers
Hematology & Oncology in Santa Rosa13 providers

Hematology & Oncology providers in California

Listed by city, largest first. Payment figures come from the federal Open Payments program, which requires drug and device companies to report what they pay physicians for consulting, speaking, meals, travel and royalties. A disclosed payment is a financial relationship, not evidence of wrongdoing, and many totals reflect a single meal. Figures cover calendar year 2025.

Dr. Darwin Roman, M.D.
Newport Beach, CA · $43 in drug and device payments (2025) · Telehealth · (657) 241-9805
Dr. David Benjamin, MD
Newport Beach, CA · $35,136 in drug and device payments (2025) · Telehealth · (714) 456-8100
Dr. Dilruba Haque, M.D.
Newport Beach, CA · $3,718 in drug and device payments (2025) · Telehealth · (949) 999-1400
Dr. Eric Zhuang, MD
Newport Beach, CA · $559 in drug and device payments (2025) · (949) 891-1441
Dr. George Semeniuk, M.D.
Newport Beach, CA · $124,853 in drug and device payments (2025) · Telehealth · (949) 763-2204
Dr. Greg Angstreich, MD
Newport Beach, CA · $129 in drug and device payments (2025) · Telehealth · (949) 646-6441
Dr. Irina Sachelarie, M.D.
Newport Beach, CA · No drug or device payments recorded (2025) · Telehealth · (657) 241-9805
Dr. Louis Vandermolen, M.D.
Newport Beach, CA · $29 in drug and device payments (2025) · Telehealth · (949) 646-6441
Dr. Minh Nguyen, MD
Newport Beach, CA · $301 in drug and device payments (2025) · Telehealth · (949) 722-0350
Dr. Misagh Karimi, MD
Newport Beach, CA · $126,942 in drug and device payments (2025) · Telehealth · (949) 763-2204
Dr. Neil Barth, M.D.
Newport Beach, CA · No drug or device payments recorded (2025) · (949) 553-3330
Dr. Robert Carroll, M.D.
Newport Beach, CA · $1,483 in drug and device payments (2025) · (949) 553-3330
Dr. Robert Dillman, MD FACP
Newport Beach, CA · No drug or device payments recorded (2025) · (949) 764-8091
Dr. Sara Beygi, M.D.
Newport Beach, CA · No drug or device payments recorded (2025) · (610) 209-9847
Dr. Sharmeen Mahmood
Newport Beach, CA · $918 in drug and device payments (2025) · Telehealth · (949) 764-4060
Dr. Simon Khagi, M.D.
Newport Beach, CA · $38,756 in drug and device payments (2025) · Telehealth · (949) 764-4060
Dr. Tingting Tan, M.D. PH.D.
Newport Beach, CA · No drug or device payments recorded (2025) · Telehealth · (949) 763-2204
Dr. Wade Smith, M.D.
Newport Beach, CA · $35 in drug and device payments (2025) · Telehealth · (949) 763-2204
Dr. Wael Harb, MD
Newport Beach, CA · $117 in drug and device payments (2025) · (949) 272-2095
Dr. Carl Singerman, MD
Northridge, CA · No drug or device payments recorded (2025) · (818) 700-2336
Dr. Draupadi Talreja, M.D.
Northridge, CA · $1,943 in drug and device payments (2025) · (818) 886-0945
Dr. Jerome Davidson, MD
Northridge, CA · No drug or device payments recorded (2025) · (818) 700-2336
Dr. Sheldon Davidson, MD
Northridge, CA · No drug or device payments recorded (2025) · (818) 700-2336
Dr. Vinita Singh, MD
Northridge, CA · $1,416 in drug and device payments (2025) · (818) 435-8819
Dr. Alan Pryor, M.D.
Novato, CA · No drug or device payments recorded (2025) · (415) 883-2021
Dr. Shaninder Kaur, M.D.
Novato, CA · No drug or device payments recorded (2025) · (415) 897-4741
Dr. Sorbarikor Piawah, M.D.
Novato, CA · No drug or device payments recorded (2025) · Telehealth · (415) 600-0110
Dr. Alice Reier, M.D.
Oakland, CA · No drug or device payments recorded (2025) · (510) 834-3700
Dr. An Uche, M.D
Oakland, CA · $198 in drug and device payments (2025) · (415) 429-9294
Dr. David Baer, MD
Oakland, CA · No drug or device payments recorded (2025) · (510) 752-1000
Dr. David Pfister, M.D.
Oakland, CA · No drug or device payments recorded (2025) · (510) 452-3375
Dr. James Breeden, MD
Oakland, CA · No drug or device payments recorded (2025) · (510) 752-1000
Dr. Karina D'souza, MD, MPH
Oakland, CA · $132 in drug and device payments (2025) · (510) 437-4800
Dr. Mala Reddy, MD
Oakland, CA · No drug or device payments recorded (2025) · (510) 752-1000
Dr. Martha Tracy, M.D.
Oakland, CA · No drug or device payments recorded (2025) · (510) 834-6923
Dr. Neha Damle, M.D.
Oakland, CA · $1,241 in drug and device payments (2025) · Telehealth · (510) 752-1000
Dr. Peter Gordon, MD
Oakland, CA · No drug or device payments recorded (2025) · (510) 752-1000
Dr. Raleigh Fatoki
Oakland, CA · $890 in drug and device payments (2025) · (510) 752-1000
Dr. Stephen Yee, MD
Oakland, CA · $43 in drug and device payments (2025) · (510) 437-4323
Dr. Tom Lee, M. D.
Oakland, CA · No drug or device payments recorded (2025) · (510) 271-7999
Dr. Yan Li, MD
Oakland, CA · No drug or device payments recorded (2025) · (510) 752-1000
Dr. Catherine Quinn, M.D.
Oceanside, CA · $2,708 in drug and device payments (2025) · Telehealth · (760) 758-5770
Dr. David Oblon, MD
Oceanside, CA · No drug or device payments recorded (2025) · (760) 758-5770
Dr. Himani Singh, MD
Oceanside, CA · $1,327 in drug and device payments (2025) · Telehealth · (760) 758-5770
Dr. Nayyar Siddique, MD
Oceanside, CA · $1,305 in drug and device payments (2025) · (760) 758-5770
Dr. Warren Paroly, MD
Oceanside, CA · $1,018 in drug and device payments (2025) · Telehealth · (760) 758-5770
Dr. Alexander Minella, M.D.
Orange, CA · No drug or device payments recorded (2025) · (800) 465-3203
Dr. Angela Fleischman, MD
Orange, CA · $48,308 in drug and device payments (2025) · Telehealth · (714) 456-8000
Dr. April Choi, MD
Orange, CA · $421 in drug and device payments (2025) · Telehealth · (714) 456-5153
Dr. Arash Rezazadeh Kalebasty, M.D.
Orange, CA · $69,977 in drug and device payments (2025) · Telehealth · (714) 456-8000

Conditions Hematology & Oncology providers in California commonly treat

Patients often search by condition rather than specialty. These are conditions typically managed by Hematology & Oncology providers. Individual practices vary, so confirm with the provider before booking.

Common questions

How many Hematology & Oncology providers are in California?

There are 1,582 Hematology & Oncology providers with active NPI records practicing in California, according to federal NPPES data refreshed monthly.

Do Hematology & Oncology providers in California offer telehealth?

Yes. 855 of the 1,582 Hematology & Oncology providers in California (about 54%) report offering telehealth services in CMS data.

Which cities in California have the most Hematology & Oncology providers?

Los Angeles (152), San Diego (89), Sacramento (77) have the highest concentration of Hematology & Oncology providers in California.

How many Hematology & Oncology providers in California received drug or device company payments?

995 of 1,582 Hematology & Oncology providers in California (63%) received at least one payment from a drug or device company in 2025, according to the federal Open Payments program.

What conditions do Hematology & Oncology providers in California treat?

Hematology & Oncology providers commonly treat breast cancer, lung cancer, lymphoma, leukemia, anemia and related conditions. Individual practices vary, so confirm with the provider before booking.

Where does this data come from?

Provider counts and profiles come from the federal NPPES registry and CMS Doctors and Clinicians files. Payment figures come from the CMS Open Payments program for calendar year 2025. The directory refreshes monthly.

Do most Hematologists and Oncologists in California work in independent practices or large health systems?

Among 1,081 Hematologists and Oncologists in California enrolled in Medicare, 11% bill through a solo or small practice with fewer than 10 clinicians, 12% through a mid-size group of 10 to 99, and 77% through a large group or health system with 100 or more clinicians, according to CMS enrollment records.

Which hospitals do Hematologists and Oncologists in California work at?

According to CMS facility affiliation records, the California hospitals where the most Hematologists and Oncologists hold privileges are Ronald Reagan UCLA Medical Center in Los Angeles; Uci Health-Orange in Orange; Santa Monica - UCLA Med Ctr & Orthopaedic Hospital in Santa Monica.

Related reading on HealthcareDiscovery.AI

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Sources: NPPES (CMS), Doctors and Clinicians national files, CMS Open Payments 2025. Updated monthly. Records are public federal data and are not verified credentials, licensure checks, or endorsements. This directory is informational and not medical advice. How we build this directory. Are you a Hematology & Oncology in California? Get featured.