Nicolaj Andersen, MD
NPI 1659455640 · Hematology & Oncology Physician · Santa Rosa, CA
Enrolled with Medicare as Practitioner - Hematology/Oncology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Nicolaj Andersen, MD is a Hematology & Oncology Physician provider in Santa Rosa, CA (NPI 1659455640).
Provider details
- NPI number
- 1659455640
- Entity type
- Individual
- Primary specialty
- Hematology & Oncology PhysicianAllopathic & Osteopathic Physicians
- Credential
- MD
- Sex
- Male
- Sole proprietor
- No
- License
- A90797 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure38% of score
19 yrs in NPPES registry
- Profile completeness38% of score
100% of core fields populated
- Practice footprint23% of score
1 documented practice location
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 methodology.
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 43 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Abiraterone Acetate | 180 | 29 |
| Zanubrutinibbrand: Brukinsa | 165 | 19 |
| Prednisone | 108 | 48 |
| Lenalidomide | 107 | 14 |
| Dexamethasone | 86 | 48 |
| Anastrozole | 75 | 30 |
| Filgrastim-Aafibrand: Nivestym | 63 | 13 |
| Enzalutamidebrand: Xtandi |
Practice location
Mailing address
Registry dates
- Enumerated
- 2006-10-25
- Last updated
- 2021-12-22
Frequently asked questions
- What is Nicolaj Andersen's NPI number?
- Nicolaj Andersen's National Provider Identifier (NPI) is 1659455640, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Nicolaj Andersen's specialty?
- Nicolaj Andersen is listed in the NPPES registry with a primary specialty of Hematology & Oncology Physician (Allopathic & Osteopathic Physicians).
- Where is Nicolaj Andersen located?
- Nicolaj Andersen's practice location on file with NPPES is 401 Bicentennial Way, Santa Rosa, CA 95403-2149.
- What is Nicolaj Andersen's phone number?
- The practice phone number listed in the NPPES registry for Nicolaj Andersen is (707) 571-4000.
- Does Nicolaj Andersen accept Medicare?
- Nicolaj Andersen is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Nicolaj Andersen's NPI active?
- Yes — Nicolaj Andersen's NPI (1659455640) is active in the NPPES registry as of the last update on 2021-12-22.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.