Ostap G. Melnyk, MD
Hematology & Oncology Physician · San Leandro, CA
Ostap G. Melnyk, MD is a hematology & oncology physician with a practice address in San Leandro, California, and NPI 1205834702, issued on Jul 8, 2005. Check the license (California G66164, as entered in NPPES) on the Medical Board of California; the Medicare figures below come from public CMS files.
- Name
- Ostap G. Melnyk
- Credential
- MD
- Primary taxonomy
- Hematology & Oncology Physician 207RH0003X
- License number
- G66164 CA
Self-reported in NPPES; status is on the state search - Practice location
- 13847 E 14TH St, San Leandro, CA 94578
- Phone
- (510) 483-2555
- Enumerated
- Jul 8, 2005
- Record last updated
- May 14, 2013 (not updated in 13 years: call before relying on the address or phone)
- Fax
- (510) 483-1856
- Medicare enrollment
- Enrolled (PECOS I20080616000717); may accept Medicare assignment
- Medical or professional school
- University Of Chicago, Pritzker School Of Medicine, 1985
- Entity
- Type 1 · individual
8 nearest hematology & oncology physician records → All 1,583 in California → Look up another NPI →
Also registered at 13847 E 14TH St
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Miles Adler, M.D.Gastroenterology Physician1760414502
- Ravinder Arora, MDHematology & Oncology Physician1952307720
- Clarence Boyd, M.D.Orthopaedic Surgery Physician1326056557
- Garfield Bryant, M.D.Surgery Physician1952402109
- James Bryant, MDSurgery Physician1750454708
- Christi Cheng, MDFamily Medicine Physician1982674685
Verify Ostap G. Melnyk in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersMedical Board of California
Search for license G66164Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
35% fewer Medicare Part D claims than the average hematology & oncology physician in 2024
574 Medicare Part D claims for 156 beneficiaries, against an average of 877 among the 10,784 providers of this specialty who prescribed in Part D. Brand-name drugs were 21% of claims. 48 claims were for opioids.
Most prescribed
- Letrozole66 claims
- Hydroxyurea41 claims
- Prochlorperazine Maleate32 claims
- Omeprazole28 claims
- Acyclovir26 claims
- Brukinsa26 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: $1,141.08
44 payments; by number, the most common kind was food and beverage; the largest payer was Pfizer 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.
Ostap G. Melnyk among 1,583 hematology & oncology physician records in California
Ostap G. Melnyk, MD 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 2005, is newer than 0% of them.
- NPI issued2005 · 0% of these records are older, 92% newer
- In a Medicare fileYes · 83% of these records are
- In the CMS Doctors and Clinicians fileYes · 71% of these records are
- Graduated1985 · median 2003 among the 1,124 with a school on file
- Record last updated2013 · 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 San Leandro → Hematology & Oncology Physician nationwide →
The 8 hematology & oncology physician records with the nearest ZIP codes
- Ravinder Arora, MDSan Leandro, CA 945781952307720
- Bao Lam, M.D.San Leandro, CA 945781639354970
- Ming Kuan, M.D.San Leandro, CA 945771043279995
- Kenneth PoonSan Leandro, CA 945771366768541
- Gail Wagner, M.D.San Leandro, CA 945771780756593
- Swaminathan MurugappanSan Ramon, CA 945821336301852
- Gregory Smith, M.D.St Helena, CA 945741265408447
- Amanpreet Buttar, MDDublin, CA 945681962679753
Common questions
What is Ostap G. Melnyk, MD's NPI number?
Ostap G. Melnyk, MD's National Provider Identifier (NPI) is 1205834702, issued on Jul 8, 2005. An NPI identifies a provider in billing; it is not a license.
Where is Ostap G. Melnyk, MD located?
The NPPES record lists a practice address at 13847 E 14TH St, San Leandro, CA, 94578. Phone: (510) 483-2555. Providers update this record themselves, so call before visiting.
How can I verify Ostap G. Melnyk, MD's license?
NPPES lists California license number G66164, 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 Ostap G. Melnyk, MD prescribe under Medicare Part D?
In 2024, Ostap G. Melnyk, MD had 574 Medicare Part D claims for 156 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.
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.