Quick answers
- Does Mariko Fitzgibbons accept Medicare assignment?
- Yes. Medicare's clinician data says Mariko Fitzgibbons accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
- How many Medicare patients does Mariko Fitzgibbons see?
- In 2024, CMS data shows 1,160 Original Medicare patients and 2,066 services for Mariko Fitzgibbons. This counts Original Medicare only and measures volume, not quality.
- What is Mariko Fitzgibbons's NPI number?
- 1396050365. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.
Medicare activity in 2024
Official CMS public-use data for Mariko Fitzgibbons, 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.
| Original Medicare patients | 1,160 |
|---|---|
| Services billed to Medicare | 2,066 |
| Different services or procedures | 80 |
| Participating Medicare provider | Yes |
| Average age of these patients | 71 |
Most frequent services
- Mri scan of brain before and after contrast (70553)453 services
- Ct scan of chest with contrast (71260)278 services
- Ct scan of soft tissue of neck with contrast (70491)225 services
- Ct scan head or brain without contrast (70450)117 services
- Ct scan of abdomen and pelvis with contrast (74177)110 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 blood pressure75%
- High cholesterol71%
- Cancer (breast, colorectal, lung, prostate, endometrial or leukemia/lymphoma)51%
- Arthritis46%
- Diabetes36%
- Ischemic heart disease33%
Practice locations
Addresses where Mariko Fitzgibbons is enrolled with Medicare (CMS data updated October 2, 2026). The first 5 of 6; the Medicare profile lists all.
- 1000 FivepointIrvine, CA 92618 (949) 671‑4673
- 1500 Duarte RdDuarte, CA 91010 (626) 256‑4673
- 1500 E Duarte RdDuarte, CA 91010
- 209 Fair Oaks AveSouth Pasadena, CA 91030 (626) 396‑2900
- 320 W 6th StCorona, CA 92882 (951) 898‑2828
Group practices
Medicare enrollment lists Mariko Fitzgibbons as a member of this group (CMS data updated October 2, 2026).
- City of Hope Medical Foundation982 clinicians in the group
Specialties
- Diagnostic Radiologyprimary
Other radiologists in Irvine
Clinicians with the same Medicare primary specialty in Irvine, CA — not a recommendation.
Other clinicians in City of Hope Medical Foundation
Medicare enrollment lists these clinicians in the same group practice — not a recommendation.
Clinician information
| Credential | MD |
|---|---|
| Medical school | Northwestern University Feinberg Medical School |
| Graduation year | 2010 (16 years since medical school) |
| Gender (as listed) | Female |
| Medicare assignment | Accepts (Medicare-approved amount as full payment) |
| NPI (National Provider Identifier) | 1396050365 |
| Corrections | Report an error or suggest an update → |
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
- National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
- Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
- NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
- Medicare Care Compare — official Medicare tool to look up clinicians