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Dr. Susan R. Lessin, M.D.

Hematology & Oncology Physician in Sunnyvale, CA · enumerated 2005.

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

National Provider Identifier

1629066618

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Registry record

Entity type Individual (Type 1)
Name Dr. Susan R. Lessin
Credential M.D.
Sex Female
Practice address 585 N Mary Ave, Sunnyvale, CA, 94085
Phone (408) 730-5100
Fax (408) 730-8726
Enumeration date Oct 12, 2005
Last updated in NPPES Jan 27, 2016

Taxonomy & licenses

174400000X Specialist Other Service Providers Secondary
207RH0003X Hematology & Oncology Physician Allopathic & Osteopathic Physicians · License G44586 (CA) Primary
MD · Doctor of Medicine: A physician who completed medical school (allopathic medicine), residency training, and state licensure. About the MD credential

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

What is the NPI number for Susan Lessin?
The National Provider Identifier (NPI) for Susan Lessin is 1629066618, a Type 1 (individual) record in the CMS NPPES registry.
Where does Susan Lessin practice?
The practice location on file with NPPES is in Sunnyvale, CA. Providers can have multiple locations; NPPES lists the primary practice address.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2016-01-27.