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Dr. Mark Massak, D.O.

Vascular & Interventional Radiology Physician in Chambersburg, PA · enumerated 2013.

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

National Provider Identifier

1952740532

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Registry record

Entity type Individual (Type 1)
Name Dr. Mark Massak
Credential D.O.
Sex Male
Practice address 12 St. Paul Drive, Wellspan Radiology, Chambersburg, PA, 17201
Phone (717) 217-6026
Enumeration date Jun 18, 2013
Last updated in NPPES Feb 2, 2026

Taxonomy & licenses

2085R0204X Vascular & Interventional Radiology Physician Allopathic & Osteopathic Physicians · License OS020464 (PA) Primary
DO · Doctor of Osteopathic Medicine: A fully licensed physician trained in osteopathic medical schools, with the same practice rights as an MD. About the DO 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

How do I verify Mark Massak's NPI record?
Cross-check NPI 1952740532 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.
Is NPI 1952740532 active?
Yes, as of the latest NPPES snapshot, NPI 1952740532 is active (record last updated 2026-02-02).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2026-02-02.