Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.

Dr. William C Guenther Jr., MD

Individual provider Hematology & Oncology Physician · NPI 1386789618

Dr. William C Guenther Jr., MD is a Hematology & Oncology Physician in Appleton, Wisconsin. Licensed in Wisconsin. Registered with an NPI since 2007.

Licensed in
WI
In the registry since
2007
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Address checks out

3925 N Gateway Dr
Appleton, WI 54913-7863
Phone: (920) 749-1171
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Hematology & Oncology Physician (primary) Taxonomy 207RH0003X · Licence 29203 (WI)

Record details

NPI number1386789618
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedFebruary 21, 2007
Last updated in NPPESJanuary 10, 2017
Mailing address3232 N Ballard Rd, Suite 200, Appleton, WI 54911-8804

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