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Ellen L Ziaja, MD

Radiation Oncology Physician in Summit, WI · enumerated 2006.

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

National Provider Identifier

1104868181

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Registry record

Entity type Individual (Type 1)
Name Ellen L Ziaja
Credential MD
Sex Female
Practice address 36500 Aurora Dr, Summit, WI, 53066
Phone (262) 434-1800
Fax (414) 649-5309
Enumeration date Jun 12, 2006
Last updated in NPPES Sep 15, 2023

Taxonomy & licenses

2085R0001X Radiation Oncology Physician Allopathic & Osteopathic Physicians · License 39952 (WI) 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
32461100 Medicaid WI -

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 NPI 1104868181 active?
Yes, as of the latest NPPES snapshot, NPI 1104868181 is active (record last updated 2023-09-15).
How do I verify Ellen Ziaja's NPI record?
Cross-check NPI 1104868181 against the official CMS registry at npiregistry.cms.hhs.gov. This page mirrors the same public NPPES data with a monthly snapshot.

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2023-09-15.