Michael Z. Koontz, MD

Medicare activity in 2024

Official CMS public-use data for Michael Z. Koontz, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Most frequent services

1. Injection, ferric carboxymaltose, 1 mg (J1439)42,000 services
2. Injection, darbepoetin alfa, 1 microgram (non-esrd use) (J0881)19,641 services
3. Injection, filgrastim (g-csf), excludes biosimilars, 1 microgram (J1442)18,480 services
4. Injection, pembrolizumab, 1 mg (J9271)15,000 services
5. Injection, oxaliplatin, 0.5 mg (J9263)11,320 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

• High cholesterol75%
• High blood pressure72%
• Cancer (breast, colorectal, lung, prostate, endometrial or leukemia/lymphoma)46%
• Arthritis43%
• Ischemic heart disease37%
• Diabetes28%

Hospitals where Michael Z. Koontz works

Medicare's Facility Affiliation Data lists Michael Z. Koontz at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

• Community Hospital of the Monterey PeninsulaMonterey, CA · Acute Care Hospital · Medicare rating: 4 of 5 stars · Emergency services: listed by Medicare · CCN 050145

Practice locations

Addresses where Michael Z. Koontz is enrolled with Medicare (CMS data updated October 2, 2026).

• 5 Harris Ct, Suite 201Monterey, CA 93940 (831) 375‑4105

Group practices

Medicare enrollment lists Michael Z. Koontz as a member of this group (CMS data updated October 2, 2026).

• Monterey Bay Oncology a Medical Corporation16 clinicians in the group

Specialties

• Medical Oncologyprimary
• Internal Medicinealso

Find other Medical Oncology doctors in California →

Other oncologists in California

Clinicians with the same Medicare primary specialty in California — not a recommendation.

• Thomas P. Bradley, MD
• Nancy Rubin, MD
• Lucio M. Nobile, MD
• Eric Chang, MD
• Shafqat Akhtar, MD
• Sandhya Srinivas, MD
• Alexander Chehrazi-Raffle, MD
• Karla P. Olmedo Gutierrez, MD

All oncologists in California →

Other clinicians in Monterey Bay Oncology a Medical Corporation

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

• Katrina Fischer, MD
• Simranjit Sekhon, MD
• Vanessa I. Anaya, PA
• Amir Tabatabai, MD
• Raina M. Ferzoco, MD
• Nancy Rubin, MD

Clinician information

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
6. Medicare Care Compare — official Medicare tool to look up clinicians