NPPES file of Aug 9, 2026

Michael L. Mahacek, MD

Radiation Oncology Physician · Grand Rapids, MI

Michael L. Mahacek, MD is a radiation oncology physician with a practice address in Grand Rapids, Michigan, and NPI 1922021484, issued on Jul 25, 2006. Check the license (Michigan 053126, as entered in NPPES) on the Michigan Board of Medicine (LARA); the Medicare figures below come from public CMS files.

Record from CMS NPPES, file of Aug 9, 2026 · Medicare files 2023 and 2024 · method · Verify with CMS →

NPPES recordNPPES file of Aug 9, 2026
1922021484
Name
Michael L. Mahacek
Credential
MD
Primary taxonomy
Radiation Oncology Physician 2085R0001X
License number
053126 MI
Self-reported in NPPES; status is on the state search
Practice location
100 Michigan St NE, Grand Rapids, MI 49503
Phone
(616) 391-1830
Enumerated
Jul 25, 2006
Record last updated
Dec 9, 2025
Fax
(616) 391-1286
Medicaid ID
2933716 MI
Medicare enrollment
Enrolled (PECOS I20100604001158); accepts Medicare assignment
Medical or professional school
Michigan State University College Of Human Medicine, 1988
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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Also registered at 100 Michigan St NE

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

  1. Aly Abdel-Mageed, MDPediatric Hematology & Oncology Physician1851361190
  2. Muriam Afzal, MDFamily Medicine Physician1174759906
  3. Shefali Aggarwal, M.DPediatric Critical Care Medicine Physician1720408313
  4. Muhammad Ali Akbar, MDInternal Medicine Physician1518529742
  5. Ghassan Al Nabhan, M.D.Internal Medicine Physician1326458068
  6. Zain AlajjouriEmergency Medicine Physician1366183295

Verify Michael L. Mahacek in five checks

  1. 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
  2. 2LicenseActive license and public ordersMichigan Board of Medicine (LARA)
    Search for license 053126
    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 Michigan 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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15% more Medicare Part D claims than the average radiation oncology physician in 2024

154 Medicare Part D claims for 69 beneficiaries, against an average of 134 among the 4,851 providers of this specialty who prescribed in Part D.

  1. Michael Mahacek154
  2. Specialty average134

Most prescribed

  1. Tamsulosin Hcl101 claims
  2. Oxybutynin Chloride Er13 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.

No measured MIPS final score for 2023

CMS assigned the neutral MIPS final score of 75 without scoring Quality, Cost, Promoting Interoperability or Improvement Activities. It is an administrative threshold, so PlainDoctor does not compare it with measured clinicians.

Source: CMS Quality Payment Program, MIPS performance year 2023, group reporting; category weights for 2023 (qpp.cms.gov).

Industry payments in 2024: $22.71

1 payment: food and beverage; the largest payer was Sumitomo Pharma America, Inc. The 3,275 providers of this specialty with any payment received $1,897.85 on average. Payments are reported by manufacturers, not by the provider, and are not a sign of wrongdoing.

  1. Michael Mahacek$22.71
  2. Specialty average$1,897.85

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. Radiation Oncology Centers PCHolland, MI

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

Michael L. Mahacek among 239 radiation oncology physician records in Michigan

Michael L. Mahacek, MD is one of 239 radiation oncology physician records with a practice address in Michigan. 79% 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 7% of them.

  • NPI issued2006 · 7% of these records are older, 55% newer
  • In a Medicare fileYes · 79% of these records are
  • In the CMS Doctors and Clinicians fileYes · 72% of these records are
  • Graduated1988 · median 2005 among the 172 with a school on file
  • Record last updated2025 · 54% of these records were not updated in five years or more

Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 2085R0001X and a Michigan practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).

Radiation Oncology Physician providers in Michigan

There are 239 radiation oncology physician records in Michigan.

The 8 radiation oncology physician records with the nearest ZIP codes

  1. Joshua Corteville, MDGrand Rapids, MI 495031093203457
  2. John Edlund, MDGrand Rapids, MI 495031841215878
  3. Celine Eid, MDGrand Rapids, MI 495031447047774
  4. Patrick Fabrizio, MDGrand Rapids, MI 495031356350938
  5. Anudeeta Gautam, MDGrand Rapids, MI 495031699562017
  6. Robert Kirkland, MDGrand Rapids, MI 495031578940029
  7. Brandon Mancini, M.D.Grand Rapids, MI 495031366731838
  8. Caroline Oska, M.D.Grand Rapids, MI 495031952006736

Common questions

What is Michael L. Mahacek, MD's NPI number?

Michael L. Mahacek, MD's National Provider Identifier (NPI) is 1922021484, issued on Jul 25, 2006. An NPI identifies a provider in billing; it is not a license.

Where is Michael L. Mahacek, MD located?

The NPPES record lists a practice address at 100 Michigan St NE, Grand Rapids, MI, 49503. Phone: (616) 391-1830. Providers update this record themselves, so call before visiting.

How can I verify Michael L. Mahacek, MD's license?

NPPES lists Michigan license number 053126, as entered by the provider. Search the Michigan Board of Medicine (LARA) at https://aca-prod.accela.com/MILARA/GeneralProperty/PropertyLookUp.aspx?isLicensee=Y&TabName=APO. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.

How much does Michael L. Mahacek, MD prescribe under Medicare Part D?

In 2024, Michael L. Mahacek, MD had 154 Medicare Part D claims for 69 beneficiaries; the average among radiation oncology physician prescribers was 134. Part D covers Medicare prescriptions only.

What is Michael L. Mahacek, MD's MIPS final score?

CMS assigned the neutral MIPS final score of 75 for 2023 without scoring any category, so it is not a measured result.

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.