NPPES file of Aug 9, 2026

Marwan Massouh, MD

Hematology & Oncology Physician · Westlake, OH

Marwan Massouh, MD is a hematology & oncology physician with a practice address in Westlake, Ohio, and NPI 1508841669, issued on Dec 13, 2005. Check the license (Ohio 35056179, as entered in NPPES) on the State Medical Board of Ohio; 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
1508841669
Name
Marwan Massouh
Credential
MD
Primary taxonomy
Hematology & Oncology Physician 207RH0003X
License number
35056179 OH
Self-reported in NPPES; status is on the state search
Practice location
29101 Health Campus Dr, Westlake, OH 44145
Phone
(440) 808-6500
Enumerated
Dec 13, 2005
Record last updated
Jul 13, 2026
Fax
(440) 808-8865
Medicaid ID
0848382 OH
Medicare enrollment
Enrolled (PECOS I20150921002541); accepts Medicare assignment
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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Also registered at 29101 Health Campus Dr

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

  1. Erin Callahan, CNMAdvanced Practice Midwife1437111945
  2. Ioana Cirstescu, D.D.S.General Practice Dentistry1255460655
  3. Renuka Diwan, M.D.MOHS-Micrographic Surgery Physician1477636850
  4. Wendy Hepner, M.C.Audiologist1679644389
  5. Susan Kall, M.A.Speech-Language Pathologist1740351428
  6. Kristine Kinsey, CNPFamily Nurse Practitioner1902628381

Verify Marwan Massouh in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersState Medical Board of Ohio
    Search for license 35056179
    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 Ohio 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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4% more Medicare Part D claims than the average hematology & oncology physician in 2024

910 Medicare Part D claims for 193 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. 43 claims were for opioids.

  1. Marwan Massouh910
  2. Specialty average877

Most prescribed

  1. Potassium Chloride83 claims
  2. Letrozole71 claims
  3. Eliquis42 claims
  4. Prednisone37 claims
  5. Xtandi32 claims
  6. Xarelto31 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: $62.28

1 payment: food and beverage; the largest payer was Emd Serono, 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. Marwan Massouh$62.28
  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. Scl Health Medical Group-Butte LLCButte, MT

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

Marwan Massouh among 513 hematology & oncology physician records in Ohio

Marwan Massouh, MD is one of 513 hematology & oncology physician records with a practice address in Ohio. 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, 84% newer
  • In a Medicare fileYes · 83% of these records are
  • In the CMS Doctors and Clinicians fileYes · 72% of these records are
  • Graduated1982 · median 2001 among the 369 with a school on file
  • Record last updated2026 · 53% 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 Ohio 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 Ohio

There are 513 hematology & oncology physician records in Ohio.

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

  1. Richard Chang, MDWestlake, OH 441451285620468
  2. Alan Lubin, MDMayfield Hts, OH 441431265439442
  3. Dale Cowan, MDBrecksville, OH 441411548374739
  4. James SchusterStrongsville, OH 441361730611682
  5. Elnora Spradling, MDStrongsville, OH 441361194040493
  6. Jason Valent, M.D.Strongsville, OH 441361013936871
  7. Bennett Yu, M.D.Strongsville, OH 441361609922343
  8. Housam Haddad, MDIndependence, OH 441311497042832

Common questions

What is Marwan Massouh, MD's NPI number?

Marwan Massouh, MD's National Provider Identifier (NPI) is 1508841669, issued on Dec 13, 2005. An NPI identifies a provider in billing; it is not a license.

Where is Marwan Massouh, MD located?

The NPPES record lists a practice address at 29101 Health Campus Dr, Westlake, OH, 44145. Phone: (440) 808-6500. Providers update this record themselves, so call before visiting.

How can I verify Marwan Massouh, MD's license?

NPPES lists Ohio license number 35056179, as entered by the provider. Search the State Medical Board of Ohio at https://elicense.ohio.gov/oh_verifylicense. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.

How much does Marwan Massouh, MD prescribe under Medicare Part D?

In 2024, Marwan Massouh, MD had 910 Medicare Part D claims for 193 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.