MICHAEL L MAHACEK MD
NPI 1922021484
Radiology - Radiation Oncology in Grand Rapids, MI

Q: What is Michael Mahacek's NPI number?

The NPI number for Michael Mahacek is 1922021484. It was assigned to this individual provider in the NPPES registry on July 25, 2006.

Q: What is Michael Mahacek's specialty?

The primary specialty registered for this NPI is Radiology, specializing in Radiation Oncology, with taxonomy code 2085R0001X.

Q: When was this NPI record last updated?

The NPPES record for Michael Mahacek was last updated on December 9, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.

Active since July 25, 2006PECOS EnrolledAccepts Medicare Assignment

75/100

CMS Quality Rating

100 MICHIGAN ST NE, GRAND RAPIDS, MI 49503(616) 391-1830(616) 391-1286 Get Directions Write a Review

NPPES record last updated: December 9, 2025. Verified against the NPPES registry weekly; last sync: August 16, 2026.

On this page

About Michael L Mahacek Md NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

MICHAEL L MAHACEK MD (NPI 1922021484) is an individual radiation oncology provider in Grand Rapids, Michigan, licensed in Michigan (053126) and active in the NPI registry since July 2006. He is enrolled in Medicare PECOS, is affiliated with Spectrum Health United Hospital, and is a graduate of Michigan State University College Of Human Medicine (1988).

NPPES Registry Identity

NPI1922021484

Entity TypeIndividualMale

Primary Taxonomy2085R0001X

Provider Legal NameMICHAEL L MAHACEKCredential: MD

Location Address100 MICHIGAN ST NEGrand Rapids, MI 49503-2560

Mailing Address100 Michigan St NeGrand Rapids, MI 49503-2560 · (616) 391-1830 · Fax (616) 391-1286

Phone(616) 391-1830

Fax(616) 391-1286

Sole ProprietorNo

Medical School CMSMichigan State University College Of Human MedicineGraduated 1988

Enumeration DateJuly 25, 2006

Last NPPES UpdateDecember 9, 2025

NPPES CertifiedDecember 9, 2025

✔ NPI 1922021484 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyRadiology · Radiation OncologyAllopathic & Osteopathic Physicians

Taxonomy Code2085R0001X

License✔ Licensed in MI · 053126

Definition

A radiologist who deals with the therapeutic applications of radiant energy and its modifiers and the study and management of disease, especially malignant tumors.

100 MICHIGAN ST NE, Grand Rapids, MI 49503

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Other Identifiers 2

Medicaid2933716MI

Other920001168MI · Railroad Medicare

Accepted Insurance

The full list of accepted plans is on the Insurance tab. Issuers include Ambetter from Buckeye Health Plan, Ambetter from Meridian, Ambetter Health and more.Insurance ›

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Michael L Mahacek Md is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID840181970

PECOS Enrollment IDI20100604001158

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Areas of Expertise CMS Part B claims 22

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Ct guidance for insertion of radiation therapy fields 77014

CT guidance for insertion of radiation therapy fields involves using a CT scan to accurately map the area of your body where radiation will be applied. This ensures the radiation targets only the necessary area, minimizing impact to healthy tissues.

363 services105 patients

Ct guidance for insertion of radiation therapy fields 77014

197 services38 patients

Calculation of radiation therapy dose 77300

Radiation therapy dose calculation is a process to determine the exact amount of radiation needed to treat a specific area in the body. This calculation helps ensure the treatment is effective while minimizing harm to healthy tissues. It's a key part of planning your radiation therapy.

144 services49 patients

Radiation treatment management, 5 treatment sessions 77427

Radiation treatment management involves a series of 5 sessions where targeted radiation is used to destroy or shrink cancer cells in your body. Each session is carefully planned to maximize effectiveness while minimizing harm to healthy tissues. You may experience side effects which will be closely monitored and managed for your comfort.

133 services53 patients

Design and construction of complex radiation treatment device 77334

The design and construction of a complex radiation treatment device is a process where a specialized instrument is created. This device targets harmful cells with high-energy rays to destroy or damage them, while minimizing impact on healthy cells. This aids in treating conditions like cancer.

90 services52 patients

Stereoscopic x-ray guidance for localization of target volume for the delivery of radiation therapy G6002

Stereoscopic x-ray guidance is a technique used in radiation therapy. It involves taking multiple X-ray images from different angles to create a 3D picture of the area to be treated. This helps accurately pinpoint the exact location for radiation delivery, ensuring the therapy is as effective as possible.

48 services17 patients

Design and construction of radiation treatment device for high precision radiation therapy 77338

A radiation treatment device is custom-made for each patient to target cancer cells with high precision. It's designed to focus radiation on the tumor, sparing healthy tissue. This process ensures effective therapy while minimizing side effects.

41 services31 patients

Design and construction of complex radiation treatment device 77334

36 services27 patients

Complex radiation therapy planning 77263

Complex radiation therapy planning is a process to determine the most effective way to deliver radiation to a specific area in your body. It involves detailed imaging to map your body's structure, allowing for precise targeting of cancer cells while sparing healthy tissue.

35 services34 patients

Calculation of radiation therapy dose 77300

31 services12 patients

High precision radiation therapy planning 77301

High precision radiation therapy planning involves detailed mapping of your body to target cancer cells accurately. Advanced imaging techniques help identify the exact location of the tumor, minimizing harm to healthy tissues. This personalized approach enhances effectiveness and reduces side effects.

23 services22 patients

Obtaining data needed to develop the optimal radiation treatment, 3 or more treatment areas or any number of treatment areas where special treatment is involved 77290

This procedure involves collecting necessary data to plan the best radiation treatment. It may cover 3 or more areas or any area requiring special attention. Data collection includes imaging scans and tests to understand the disease's extent and to tailor a precise, effective treatment plan.

19 services19 patients

Obtaining data needed to develop the optimal radiation treatment, 1 treatment area 77280

This procedure involves gathering essential information to create the best radiation treatment plan for a specific area. It includes scanning the treatment area and using this data to calculate the precise dose of radiation needed to target the disease effectively, while sparing healthy tissue.

18 services17 patients

Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more 99214

This is a routine check-up for patients who have previously visited our clinic. It involves a comprehensive review of your health and any ongoing treatments. The consultation lasts between 30-39 minutes, allowing enough time to discuss any concerns.

18 services17 patients

Complex radiation therapy planning 77263

17 services17 patients

New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more 99204

This is a first-time office or outpatient visit lasting between 45-59 minutes. The healthcare provider evaluates your health, discusses your medical history, and may suggest further tests or treatments. It's an opportunity to ask questions and understand your health better.

17 services17 patients

New patient office or other outpatient visit with low level of medical decision making, if using time, 30 minutes or more 99203

This service involves an initial office or outpatient visit for a new patient. The healthcare professional will spend 30-44 minutes understanding your health history, current issues, and discussing possible treatment plans. It's a comprehensive evaluation to start your healthcare journey.

16 services16 patients

Design and construction of radiation treatment device for high precision radiation therapy 77338

15 services13 patients

New patient office or other outpatient visit with moderate level of medical decision making, if using time, 45 minutes or more 99204

15 services15 patients

Special radiation treatment 77470

Special radiation treatment is a medical procedure that uses high-energy rays to destroy or damage cancer cells. It's a targeted approach that aims to minimize harm to healthy tissues. The treatment duration varies based on individual health conditions.

13 services13 patients

Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more 99215

This service involves a follow-up appointment for existing patients, lasting between 40 to 54 minutes. During this time, your healthcare provider will assess your current health status, discuss any changes or concerns, review your treatment plan, and answer any questions you may have.

12 services11 patients

Radiation treatment management, 5 treatment sessions 77427

11 services11 patients

Hospital Affiliations CMS Care Compare 5

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Spectrum Health United Hospital

Acute Care Hospitals · Greenville, MI

4/5 CMS rating

OwnershipVoluntary non-profit - Other

CMS Certification Number230035

Location615 S Bower StreetGreenville, MI 48838 · Montcalm County

Birthing friendly

Spectrum Health

Acute Care Hospitals · Grand Rapids, MI

5/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number230038

Location100 Michigan St NEGrand Rapids, MI 49503 · Kent County

Emergency services Birthing friendly

Holland Community Hospital

Acute Care Hospitals · Holland, MI

5/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number230072

Location602 Michigan AveHolland, MI 49423 · Ottawa County

Emergency services Birthing friendly

Corewell Health Ludington Hospital

Acute Care Hospitals · Ludington, MI

4/5 CMS rating

OwnershipVoluntary non-profit - Private

CMS Certification Number230110

LocationOne N Atkinson DriveLudington, MI 49431 · Mason County

Emergency services Birthing friendly

Corewell Health Reed City Hospital

Critical Access Hospitals · Reed City, MI

OwnershipVoluntary non-profit - Private

CMS Certification Number231323

Location300 N Patterson, PO Box 75Reed City, MI 49677 · Osceola County

Emergency services

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 49503 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient

$166.68 typical visit price

range $54.34 – $166.68

Typical copayment $41.67 (range $13.58 – $41.67)

Most-billed visit code 99205

Established Patient

$68.07 typical visit price

range $17.09 – $135.40

Typical copayment $17.01 (range $4.27 – $33.85)

Most-billed visit code 99213

Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Medicare Quality Performance CMS QPP · MIPS

Performance in the CMS Quality Payment Program: the MIPS final score across four weighted categories, and the individual quality measures reported to Medicare.

75/100

MIPS Final ScoreMerit-based Incentive Payment System · CMS Quality Payment Program

Scored as part of a group practice

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

MAUREEN TAN PEDRES M.D.

Internal Medicine

100 MICHIGAN ST NE, SUITE A721
GRAND RAPIDS, MI 49503

Kent County (616) 391-3139

MATTHEW H ARMSTRONG MD

Anesthesiology

100 MICHIGAN ST NE
GRAND RAPIDS, MI 49503

Kent County (616) 391-1510

ALINE DE QUADROS TEIXEIRA MD

Internal Medicine

100 MICHIGAN ST NE
GRAND RAPIDS, MI 49503

Kent County (616) 391-3139

DR. LINDSEY DANIELLE CONRADO PT, DPT

Physical Therapist

100 MICHIGAN ST NE
GRAND RAPIDS, MI 49503

Kent County (161) 639-1177

DANIEL H. ROBINSON D.O.

Anesthesiology

100 MICHIGAN ST NE
GRAND RAPIDS, MI 49503

Kent County (616) 391-1510

MARK GREENWOOD DO

Emergency Medicine

100 MICHIGAN ST NE, MC 71
GRAND RAPIDS, MI 49503

Kent County (616) 391-5310

RAYMOND SCUREK MD

Emergency Medicine

100 MICHIGAN ST NE
GRAND RAPIDS, MI 49503

Kent County (616) 391-1680

MRS. RACHEL LEIGH VANSTRIEN PA-C

Physician Assistant

100 MICHIGAN ST NE, SUITE 8861
GRAND RAPIDS, MI 49503

Kent County (616) 391-0800

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Michael Mahacek's NPI number?

The NPI number for Michael Mahacek is 1922021484. It was assigned to this individual provider in the NPPES registry on July 25, 2006.

Where is Michael Mahacek located?

Michael Mahacek practices at 100 Michigan St NE, Grand Rapids, MI 49503. The listed phone number is (616) 391-1830.

What is Michael Mahacek's specialty?

The primary specialty registered for this NPI is Radiology, specializing in Radiation Oncology, with taxonomy code 2085R0001X.

Is Michael Mahacek enrolled in Medicare?

Yes. Michael Mahacek is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

What insurance does Michael Mahacek accept?

Health plans from Ambetter Health, Ambetter from Buckeye Health Plan, Ambetter from Meridian, Blue Care Network of Michigan and Blue Cross Blue Shield of Michigan Mutual Insurance Company and 2 other insurers list Michael Mahacek as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

Is Michael Mahacek affiliated with any hospitals?

According to CMS data, Michael Mahacek is affiliated with Spectrum Health United Hospital, Spectrum Health, Holland Community Hospital, Corewell Health Ludington Hospital and Corewell Health Reed City Hospital.

When was this NPI record last updated?

The NPPES record for Michael Mahacek was last updated on December 9, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.