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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. Samer Alkassis
Irvine, CA · $374 in drug and device payments (2025) · Telehealth · (949) 653-2959
Dr. Sudarsan Kollimuttathuillam, MD
Irvine, CA · $7,691 in drug and device payments (2025) · Telehealth · (949) 333-7580
Dr. Tara Seery
Irvine, CA · $10,963 in drug and device payments (2025) · Telehealth · (949) 764-5347
Dr. Tiffanie Do, M.D.
Irvine, CA · No drug or device payments recorded (2025) · (833) 574-2273
Dr. Zorawar Noor, M.D., M.H.S.
Irvine, CA · $29 in drug and device payments (2025) · Telehealth · (949) 653-2959
Dr. Gary Shi, MD, PHD
Jackson, CA · $409 in drug and device payments (2025) · (209) 257-0292
Dr. Allan Orenstein, M.D.
La, CA · No drug or device payments recorded (2025) · (310) 649-7222
Dr. Frank Mori, M.D.
La, CA · $5,420 in drug and device payments (2025) · Telehealth · (310) 649-7222
Dr. Vasanth Kumar, M.D.
La Canada, CA · No drug or device payments recorded (2025) · (213) 595-6383
Dr. Gabor Kovacs, M.D.
Laguna Beach, CA · $109 in drug and device payments (2025) · (949) 499-3085
Dr. David Okun, M.D.
Laguna Hills, CA · No drug or device payments recorded (2025) · (949) 770-8168
Dr. Edward Wagner, M.D.
Laguna Hills, CA · $86 in drug and device payments (2025) · Telehealth · (949) 499-4540
Dr. Gol Golshani, M.D
Laguna Hills, CA · $625 in drug and device payments (2025) · Telehealth · (949) 238-4100
Dr. Howard Cheng, M.D.
Laguna Hills, CA · $565 in drug and device payments (2025) · (949) 770-8168
Dr. Jacqueline Malekirad, M.D.
Laguna Hills, CA · $49 in drug and device payments (2025) · Telehealth · (949) 380-2670
Dr. Merry Tetef, M.D.
Laguna Hills, CA · No drug or device payments recorded (2025) · (949) 458-8252
Dr. Shi Yu, M.D.
Laguna Hills, CA · No drug or device payments recorded (2025) · Telehealth · (949) 380-2670
Dr. Yulian Khagi, M.D.
Laguna Hills, CA · $77 in drug and device payments (2025) · Telehealth · (949) 238-4100
Dr. Aaron Miller, M.D., PH.D.
La Jolla, CA · No drug or device payments recorded (2025) · Telehealth · (858) 822-6226
Dr. Akram Mesleh Shayeb, M.D.
La Jolla, CA · $360 in drug and device payments (2025) · Telehealth · (858) 657-5281
Dr. Alan Saven, M.D.
La Jolla, CA · $13,701 in drug and device payments (2025) · Telehealth · (858) 554-9489
Dr. Amanda Herrmann
La Jolla, CA · $6,685 in drug and device payments (2025) · Telehealth · (858) 657-5281
Dr. Angelique Richardson, MD,PHD
La Jolla, CA · No drug or device payments recorded (2025) · (800) 926-8273
Dr. Anthony Nguyen, MD
La Jolla, CA · $8,891 in drug and device payments (2025) · Telehealth · (800) 926-8273
Dr. Arun Dang, DO
La Jolla, CA · $590 in drug and device payments (2025) · (858) 554-8788
Dr. Ayad Hamdan, M.D.
La Jolla, CA · No drug or device payments recorded (2025) · Telehealth · (858) 822-6600
Dr. Barbara Parker, M.D.
La Jolla, CA · No drug or device payments recorded (2025) · (858) 822-6200
Dr. David Hermel, MD
La Jolla, CA · $42,404 in drug and device payments (2025) · Telehealth · (858) 554-8788
Dr. Dimitrios Tzachanis, M.D.
La Jolla, CA · $369 in drug and device payments (2025) · Telehealth · (858) 554-8788
Dr. Divya Koura, M.D.
La Jolla, CA · $527 in drug and device payments (2025) · Telehealth · (858) 554-8788
Dr. Emily Nagler, MD
La Jolla, CA · $17,062 in drug and device payments (2025) · Telehealth · (858) 554-8703
Dr. Erin Roesch, M.D.
La Jolla, CA · $839 in drug and device payments (2025) · Telehealth · (858) 657-5090
Dr. Farah Nasraty
La Jolla, CA · $2,992 in drug and device payments (2025) · Telehealth · (858) 554-8788
Dr. Gregory Botta, M.D./PH.D.
La Jolla, CA · $2,054 in drug and device payments (2025) · Telehealth · (858) 554-3200
Dr. Harshitha Dudipala, MD
La Jolla, CA · $134 in drug and device payments (2025) · (330) 322-0680
Dr. Hirotaka Miyashita, MD
La Jolla, CA · No drug or device payments recorded (2025) · Telehealth · (800) 926-8273
Dr. Imawati Budihardjo, M.D., PH.D
La Jolla, CA · No drug or device payments recorded (2025) · (858) 822-6100
Dr. Jacob Leary, MD
La Jolla, CA · No drug or device payments recorded (2025) · (858) 657-5281
Dr. Jacob New, MD
La Jolla, CA · $772 in drug and device payments (2025) · Telehealth · (858) 554-8788
Dr. James Buturla, M.D.
La Jolla, CA · No drug or device payments recorded (2025) · (858) 657-5281
Dr. James Mason, M.D.
La Jolla, CA · $972 in drug and device payments (2025) · Telehealth · (858) 554-8597
Dr. James Sinclair, M.D.
La Jolla, CA · $873 in drug and device payments (2025) · (858) 552-1410
Dr. Jeffrey Andrey, M.D.
La Jolla, CA · $7,872 in drug and device payments (2025) · (858) 554-8632
Dr. Jessica Sullivan, D.O.
La Jolla, CA · $23 in drug and device payments (2025) · Telehealth · (800) 926-8273
Dr. Joan Kroener, M.D.
La Jolla, CA · No drug or device payments recorded (2025) · (858) 554-8629
Dr. Karen Resnick
La Jolla, CA · No drug or device payments recorded (2025) · (858) 657-5281
Dr. Michael Kosty, M.D.
La Jolla, CA · $113 in drug and device payments (2025) · (858) 554-9559
Dr. Nicole Farha
La Jolla, CA · No drug or device payments recorded (2025) · (858) 822-6100
Dr. Oyewale Abidoye, M.D.
La Jolla, CA · $88 in drug and device payments (2025) · (858) 558-8666
Dr. Quinne Sember
La Jolla, CA · $211 in drug and device payments (2025) · Telehealth · (858) 610-0217

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.