Gregory A. Masters, MD
Medical Oncology Physician · Newark, DE
Gregory A. Masters, MD is a medical oncology physician with a practice address in Newark, Delaware, and NPI 1508834680, issued on Mar 14, 2006. Check the license (Delaware C10006866, as entered in NPPES) on the Delaware Board of Medical Licensure and Discipline; the Medicare figures below come from public CMS files.
- Name
- Gregory A. Masters
- Credential
- MD
- Primary taxonomy
- Medical Oncology Physician 207RX0202X
- License number
- C10006866 DE
Self-reported in NPPES; status is on the state search - Practice location
- 4701 Ogletown Stanton RD, Newark, DE 19713
- Phone
- (302) 366-1200
- Enumerated
- Mar 14, 2006
- Record last updated
- Sep 27, 2007 (not updated in 19 years: call before relying on the address or phone)
- Fax
- (302) 366-1700
- Medicaid ID
- 1000022975 DE
- Medicare enrollment
- Enrolled (PECOS I20100225000458); accepts Medicare assignment
- Medical or professional school
- Northwestern University Feinberg Medical School, 1990
- Entity
- Type 1 · individual
8 nearest medical oncology physician records → All 17 in Delaware → Look up another NPI →
Also registered at 4701 Ogletown Stanton RD
A shared address usually means a shared clinic or building; it does not show who employs whom.
- Raafat Abdel-Misih, MDSurgery Physician1821088048
- Zohra Ali-Khan Catts, M.S.Genetic Counselor (M.S.)1215960869
- Thomas Bauer, MDThoracic Surgery (Cardiothoracic Vascular Surgery) Physician1679551717
- Joseph Bennett, M.D.Surgery Physician1619967841
- Mark Borowsky, MDGynecologic Oncology Physician1871570044
- Rebecca Boyd, RDRegistered Dietitian1134555352
Verify Gregory A. Masters in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersDelaware Board of Medical Licensure and Discipline
Search for license C10006866Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
1% more Medicare Part D claims than the average medical oncology physician in 2024
711 Medicare Part D claims for 138 beneficiaries, against an average of 703 among the 4,230 providers of this specialty who prescribed in Part D. 83 claims were for opioids.
Most prescribed
- Prochlorperazine Maleate61 claims
- Tagrisso59 claims
- Gabapentin51 claims
- Ondansetron Hcl35 claims
- Levothyroxine Sodium34 claims
- Mirtazapine34 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.
The MIPS final score for 2023 (Medicare payment program): 94 of 100
The Merit-based Incentive Payment System score is reported for this clinician. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.
Source: CMS Quality Payment Program, MIPS performance year 2023; category weights for 2023 (qpp.cms.gov).
Industry payments in 2024: $263.72
12 payments; by number, the most common kind was food and beverage; the largest payer was Novartis Pharmaceuticals Corporation. The 3,343 providers of this specialty with any payment received $11,773.47 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.
Bills Medicare through one group practice
- Medical Oncology Hematology Consultants PANewark, DE
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Gregory A. Masters among 17 medical oncology physician records in Delaware
Gregory A. Masters, MD is one of 17 medical oncology physician records with a practice address in Delaware. 76% 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 12% of them.
- NPI issued2006 · 12% of these records are older, 59% newer
- In a Medicare fileYes · 76% of these records are
- In the CMS Doctors and Clinicians fileYes · 76% of these records are
- Graduated1990 · median 2007 among the 13 with a school on file
- Record last updated2007 · 29% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RX0202X and a Delaware practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Medical Oncology Physician providers in Delaware
There are 17 medical oncology physician records in Delaware.
All 17 in Delaware → Every provider in Newark → Medical Oncology Physician nationwide →
The 8 medical oncology physician records with the nearest ZIP codes
- Lydia Clements, MDNewark, DE 197131942618962
- Stephen Grubbs, MDNewark, DE 197131841268927
- Susan Schaffer Whiteman, D.O.Newark, DE 197131518997147
- Matthew Diamond, MDNewark, DE 197181770044778
- Gerard Kennealey, MDWilmington, DE 198031922385046
- Victor Sandor, MDWilmington, DE 198051396933594
- Mohamad Ghraowi, MDDover, DE 199011942201439
- Ajinkya Kulkarni, MDDover, DE 199011962997668
Common questions
What is Gregory A. Masters, MD's NPI number?
Gregory A. Masters, MD's National Provider Identifier (NPI) is 1508834680, issued on Mar 14, 2006. An NPI identifies a provider in billing; it is not a license.
Where is Gregory A. Masters, MD located?
The NPPES record lists a practice address at 4701 Ogletown Stanton RD, Newark, DE, 19713. Phone: (302) 366-1200. Providers update this record themselves, so call before visiting.
How can I verify Gregory A. Masters, MD's license?
NPPES lists Delaware license number C10006866, as entered by the provider. Search the Delaware Board of Medical Licensure and Discipline at https://delpros.delaware.gov/OH_VerifyLicense. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Gregory A. Masters, MD prescribe under Medicare Part D?
In 2024, Gregory A. Masters, MD had 711 Medicare Part D claims for 138 beneficiaries; the average among medical oncology physician prescribers was 703. Part D covers Medicare prescriptions only.
What is Gregory A. Masters, MD's MIPS final score?
The 2023 MIPS final score is 94 of 100. The average among 454,083 clinicians with a measured score was 83.5.
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.