Mark Joshua Chang, DO
Hematology & Oncology Physician · Upland, CA
Mark Joshua Chang, DO is a hematology & oncology physician with a practice address in Upland, California, and NPI 1861954182, issued on Apr 4, 2019. Check the license (California 20A24887, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Mark Joshua Chang
- Credential
- DO
- Primary taxonomy
- Hematology & Oncology Physician 207RH0003X
- License numbers
- 20A24887 CA
DO3131 NV
Self-reported in NPPES; status is on the state search - Practice location
- 1100 San Bernardino RD Ste 1100, Upland, CA 91786
- Phone
- (909) 949-2242
- Enumerated
- Apr 4, 2019
- Record last updated
- Jul 8, 2026
- Fax
- (909) 981-5783
- Medicare enrollment
- Enrolled (PECOS I20260423000630); may accept Medicare assignment
- Entity
- Type 1 · individual
8 nearest hematology & oncology physician records → All 1,583 in California → Look up another NPI →
Also registered at 1100 San Bernardino RD Ste 1100
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Cecil Benitez, M.D., PH.D.Radiation Oncology Physician1578182739
- Genesis Ibarra, LCSWClinical Social Worker1043767353
- Diba Izadyar, PA-CPhysician Assistant1710520671
- Bradford Kim, M.D.Surgical Oncology Physician1215297080
- Seija Maniskas, MD, MSColon & Rectal Surgery Physician1861015729
- Melissa O'Banion, PA-CPhysician Assistant1235785528
Verify Mark Joshua Chang in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license 20A24887Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
98% fewer Medicare Part D claims than the average hematology & oncology physician in 2024
18 Medicare Part D claims, against an average of 877 among the 10,784 providers of this specialty who prescribed in Part D.
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: $643.62
7 payments; by number, the most common kind was food and beverage; the largest payer was Daiichi Sankyo 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.
Source: CMS Open Payments, program year 2024 (openpaymentsdata.cms.gov); average among providers of this specialty with at least one payment.
Mark Joshua Chang among 1,583 hematology & oncology physician records in California
Mark Joshua Chang, DO 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 2019, is newer than 95% of them.
- NPI issued2019 · 95% of these records are older, 3% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileYes · 71% of these records are
- Graduated2019 · median 2003 among the 1,124 with a school on file
- Record last updated2026 · 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).
Hematology & Oncology Physician providers in California
There are 1,583 hematology & oncology physician records in California.
All 1,583 in California → Every provider in Upland → Hematology & Oncology Physician nationwide →
The 8 hematology & oncology physician records with the nearest ZIP codes
- Camille Adeimy, MDUpland, CA 917861477785160
- Natasha GargUpland, CA 917861831458835
- Naveen Gupta, M.D.Upland, CA 917861720024128
- Shanmuga Pudunagar Subbiah, MDUpland, CA 917861699968503
- Swapnil Rajurkar, M.D.Upland, CA 917861184777468
- Neel Talwar, MDUpland, CA 917861477977114
- Chau Tran, D.O.Upland, CA 917861083813422
- Lydia Chow, M.D.West Covina, CA 917901770087314
Common questions
What is Mark Joshua Chang, DO's NPI number?
Mark Joshua Chang, DO's National Provider Identifier (NPI) is 1861954182, issued on Apr 4, 2019. An NPI identifies a provider in billing; it is not a license.
Where is Mark Joshua Chang, DO located?
The NPPES record lists a practice address at 1100 San Bernardino RD Ste 1100, Upland, CA, 91786. Phone: (909) 949-2242. Providers update this record themselves, so call before visiting.
How can I verify Mark Joshua Chang, DO's license?
NPPES lists California license number 20A24887, 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 Mark Joshua Chang, DO prescribe under Medicare Part D?
In 2024, Mark Joshua Chang, DO had 18 Medicare Part D claims; 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.
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.