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Theodore D. Masek, MD

Radiation Oncology Physician in Palm Desert, CA · enumerated 2005 · practices at Genesiscare Usa of California A Medical Corporation.

Data current as of Jul 13, 2026 · sourced from CMS NPPES

National Provider Identifier

1720073935

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Registry record

Entity type Individual (Type 1)
Name Theodore D. Masek
Credential MD
Sex Male
Practice address 77840 Flora Rd, Palm Desert, CA, 92211
Phone (760) 200-8777
Fax (760) 200-8877
Enumeration date Sep 14, 2005
Last updated in NPPES Aug 7, 2008

Taxonomy & licenses

2085R0001X Radiation Oncology Physician Allopathic & Osteopathic Physicians · License A39531 (CA) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

Other identifiers

Identifier Type State Issuer
P00253432 Other CA RAILROAD MEDICARE
00A395310 Medicaid CA -

What is an NPI number?

A National Provider Identifier (NPI) is a unique 10-digit number that CMS assigns to every U.S. healthcare provider and organization under HIPAA. Type 1 NPIs identify individual providers; Type 2 NPIs identify organizations. The NPI appears on insurance claims, prescriptions, and credentialing paperwork, and never changes, even if the provider moves or changes specialty.

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Frequently asked questions

Is this the official NPI registry?
No. NPI Portal is a private site built on public CMS NPPES data. The official registry is npiregistry.cms.hhs.gov, operated by CMS.
What specialty is Theodore Masek?
Theodore Masek is registered in NPPES with the primary taxonomy of Radiation Oncology Physician. The taxonomy code describes the provider's classification and area of specialization for claims and credentialing.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2008-08-07.