Eugene Ahn, MD
NPI 1912999533 · Radiation Oncology Physician · Simi Valley, CA
Enrolled with Medicare as Practitioner - Radiation Oncology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Eugene Ahn, MD is a Radiation Oncology Physician provider in Simi Valley, CA (NPI 1912999533).
Provider details
- NPI number
- 1912999533
- Entity type
- Individual
- Primary specialty
- Radiation Oncology PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- A71690 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
20 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)25% of score
4,246 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our .
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Ct Guidance for Insertion of Radiation Therapy Fields77014 | 1,215 | $132 |
| Intensity Modulated Treatment Delivery, Single Or Multiple Fields/Arcs,via Narrow Spatially and Temporally Modulated Beams, Binary, Dynamic Mlc, Per Treatment SessionG6015 | 1,060 | $411 |
| Radiation Treatment Delivery,3 Or More Separate Treatment Areas, Custom Blocking, Tangential Ports, Wedges, Rotational Beam, Compensators, Electron Beam; 6-10 MevG6012 | 385 | $266 |
| Continuing Radiation Therapy Consultation Per Week77336 | 318 | $102 |
| Radiation Treatment Management, 5 Treatment Sessions77427 | 277 | $198 |
| Calculation of Radiation Therapy Dose77300 | 153 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$271 across 12 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Additional practice locations (1)
- 1240 Westlake BlvdSte 103Westlake Village, CA 91361-1929Phone: (805) 494-4483Fax: (805) 494-9555
Registry dates
- Enumerated
- 2005-08-19
- Last updated
- 2022-08-05
- Certified
- 2022-08-05
Frequently asked questions
- What is Eugene Ahn's NPI number?
- Eugene Ahn's National Provider Identifier (NPI) is 1912999533, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Eugene Ahn's specialty?
- Eugene Ahn is listed in the NPPES registry with a primary specialty of Radiation Oncology Physician (Allopathic & Osteopathic Physicians).
- Where is Eugene Ahn located?
- Eugene Ahn's practice location on file with NPPES is 2985 Sycamore Dr, Simi Valley, CA 93065-1201.
- What is Eugene Ahn's phone number?
- The practice phone number listed in the NPPES registry for Eugene Ahn is (805) 584-6611.
- Does Eugene Ahn accept Medicare?
- Eugene Ahn is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Eugene Ahn's NPI active?
- Yes — Eugene Ahn's NPI (1912999533) is active in the NPPES registry as of the last update on 2022-08-05.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.