NPPES file of Aug 9, 2026

James R. Mason, M.D.

Hematology & Oncology Physician · La Jolla, CA

James R. Mason, M.D. is a hematology & oncology physician with a practice address in La Jolla, California, and NPI 1497717730, issued on Apr 3, 2006. Check the license (California G56827, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.

Record from CMS NPPES, file of Aug 9, 2026 · Medicare files 2024 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1497717730
Name
James R. Mason
Credential
M.D.
Primary taxonomy
Hematology & Oncology Physician 207RH0003X
License number
G56827 CA
Self-reported in NPPES; status is on the state search
Practice location
10710 N Torrey Pines RD, La Jolla, CA 92037
Phone
(858) 554-8597
Enumerated
Apr 3, 2006
Record last updated
Dec 3, 2019 (not updated in 7 years: call before relying on the address or phone)
Medicaid ID
00G568270 CA
Medicare enrollment
Enrolled (PECOS I20100607000545); accepts Medicare assignment
Medical or professional school
University Of California, San Francisco School Of Medicine, 1984
Telehealth
Offers telehealth (CMS)
Entity
Type 1 · individual
Public record from CMS NPPES (open it on the CMS NPI Registry). Enrollment, assignment, school and telehealth: CMS Doctors and Clinicians file, Aug 2026. A record is not a license: verify it with the state board.
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8 nearest hematology & oncology physician records → All 1,583 in California → Look up another NPI →

Also registered at 10710 N Torrey Pines RD

A shared address usually means a shared clinic or building; it does not show who employs whom.

  1. Nicole AdamsNurse Practitioner1891167029
  2. Rachel Adrian, RN, MSN, AGACNP-BCAcute Care Nurse Practitioner1548870686
  3. Laura Alberton, M.D.Sports Medicine (Orthopaedic Surgery) Physician1992770655
  4. Sonia Ali, M.D.Hematology & Oncology Physician1730451089
  5. Danica Anderson, PA-CPhysician Assistant1811601859
  6. Jacqueline Anderson, MDSurgery Physician1912427873

Verify James R. Mason in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMedical Board of California
    Search for license G56827    Check the board
  3. 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
  4. 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
  5. 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
Open the California license search

PlainDoctor does not match the HHS-OIG exclusion list to individual records: most entries carry no NPI. Search the OIG exclusion list by name.

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3% more Medicare Part D claims than the average hematology & oncology physician in 2024

902 Medicare Part D claims for 104 beneficiaries, against an average of 877 among the 10,784 providers of this specialty who prescribed in Part D. Brand-name drugs were 23% of claims.

  1. James Mason902
  2. Specialty average877

Most prescribed

  1. Acyclovir107 claims
  2. Hydroxyurea71 claims
  3. Dexamethasone59 claims
  4. Imbruvica50 claims
  5. Gabapentin36 claims
  6. Lenalidomide26 claims

Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.

Industry payments in 2024: $907.17

27 payments; by number, the most common kind was food and beverage; the largest payer was Tempus AI, Inc. The 8,560 providers of this specialty with any payment received $7,481.41 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.

  1. James Mason$907.17
  2. Specialty average$7,481.41

Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.

Bills Medicare through one group practice

  1. Scripps HealthLa Jolla, CA

Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).

James R. Mason among 1,583 hematology & oncology physician records in California

James R. Mason, M.D. is one of 1,583 hematology & oncology physician records with a practice address in California. 83% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2006, is newer than 8% of them.

  • NPI issued2006 · 8% of these records are older, 54% newer
  • In a Medicare fileYes · 83% of these records are
  • In the CMS Doctors and Clinicians fileYes · 71% of these records are
  • Graduated1984 · median 2003 among the 1,124 with a school on file
  • Record last updated2019 · 58% of these records were not updated in five years or more

Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RH0003X and a California practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

46 hematology & oncology physician records list a practice address in La Jolla

They are 46 of the 3,648 NPPES records with a practice address in La Jolla, and 1,583 hematology & oncology physician records in California.

All 1,583 in California → Every provider in La Jolla → Hematology & Oncology Physician nationwide →

The 8 hematology & oncology physician records with the nearest ZIP codes

  1. Oyewale Abidoye, M.D.La Jolla, CA 920371790841815
  2. Sonia Ali, M.D.La Jolla, CA 920371730451089
  3. Jeffrey Andrey, M.D.La Jolla, CA 920371700851482
  4. Robert BrouillardLa Jolla, CA 920371487626420
  5. Richard Burt, MDLa Jolla, CA 920371225090319
  6. Michael Kosty, M.D.La Jolla, CA 920371801857099
  7. Divya Koura, M.D.La Jolla, CA 920371053471318
  8. Joan Kroener, M.D.La Jolla, CA 920371720067150

Common questions

What is James R. Mason, M.D.'s NPI number?

James R. Mason, M.D.'s National Provider Identifier (NPI) is 1497717730, issued on Apr 3, 2006. An NPI identifies a provider in billing; it is not a license.

Where is James R. Mason, M.D. located?

The NPPES record lists a practice address at 10710 N Torrey Pines RD, La Jolla, CA, 92037. Phone: (858) 554-8597. Providers update this record themselves, so call before visiting.

How can I verify James R. Mason, M.D.'s license?

NPPES lists California license number G56827, as entered by the provider. Search the Medical Board of California at https://www.mbc.ca.gov/License-Verification/default.aspx. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.

How much does James R. Mason, M.D. prescribe under Medicare Part D?

In 2024, James R. Mason, M.D. had 902 Medicare Part D claims for 104 beneficiaries; the average among hematology & oncology physician prescribers was 877. Part D covers Medicare prescriptions only.

Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.

Written with AI tools from the named public files; every figure is computed from those files (how it is made).

Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.