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Fox Valley Hematology & Oncology, S.C.

Hematology & Oncology Physician in De Pere, WI · enumerated 2017 · authorized official William Guenther, Officer/Physician.

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

National Provider Identifier

1649716358

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Registry record

Entity type Organization (Type 2)
Legal business name Fox Valley Hematology & Oncology, S.C.
Practice address 1716 Lawrence Dr, De Pere, WI, 54115
Phone (920) 749-1171
Fax (920) 734-5307
Enumeration date Jan 19, 2017
Last updated in NPPES Jan 19, 2017

Taxonomy & classification

207RH0003X Hematology & Oncology Physician Allopathic & Osteopathic Physicians Primary

Authorized official

Name William Guenther
Title Officer/Physician
Phone (920) 749-1171

Other identifiers

Identifier Type State Issuer
000045450 Other WI PTAN
32802700 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

What is a Type 2 NPI?
A Type 2 NPI identifies an organization (group practice, hospital, pharmacy, lab), while Type 1 NPIs identify individual providers. Organizations bill under their Type 2 NPI.
What type of organization is Fox Valley Hematology & Oncology, S.C.?
Fox Valley Hematology & Oncology, S.C. is registered in NPPES as a Hematology & Oncology Physician (its primary provider taxonomy).

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Source: CMS NPPES (public data). Snapshot 2026-07-13. Provider record last updated 2017-01-19.