Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of October 4, 2026.
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Dr. Mary Uan-Sian Feng, MD

Individual provider Radiation Oncology Physician · NPI 1720106693

Dr. Mary Uan-Sian Feng, MD practises Radiation Oncology in San Francisco, California. Graduated from Washington University School of Medicine in 2002, 24 years ago. Practices with UCSF Medical Group Business Services, a 1,531-clinician group, works from 2 locations, accepts Medicare assignment and offers telehealth. Licensed in California and Michigan.

Years since qualifying
24
Trained at
Washington University School of Medicine
Licensed in
CA, MI
In the registry since
2007
Specialties on file
3
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

1825 4th Street L1101
San Francisco, CA 94143
Phone: (415) 502-7222
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Additional practice locations (1)

  • 1500 East Medical Center Dr, Ann Arbor, MI 48109-5010 — (734) 936-4300

Specialties & licences

Radiation Oncology Physician (primary) Taxonomy 2085R0001X · Licence C143118 (CA)
Radiation Oncology Physician Taxonomy 2085R0001X · Licence 4301079982 (MI)
Student in an Organized Health Care Education/Training Program Taxonomy 390200000X · Licence 4301079982 (MI)

Record details

NPI number1720106693
Entity typeIndividual (Type 1)
GenderFemale
Credentials MD
Sole proprietorNo
NPI enumeratedMarch 27, 2007
Last updated in NPPESSeptember 27, 2022
Certification dateSeptember 27, 2022

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyRADIATION ONCOLOGY
Medical schoolWASHINGTON UNIVERSITY SCHOOL OF MEDICINE
Graduated 2002 (24 years in practice)
Group practice Ucsf Medical Group Business Services — 1531 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations2 on file with Medicare

Medicare patients and services, 2024

From the CMS Medicare Physician & Other Practitioners file for calendar year 2024. It counts Original Medicare patients only, so a practice that mostly sees Medicare Advantage or privately insured patients looks smaller here than it is.

Medicare patients70
Services billed 485 a service is one billed item, such as a visit, a test or a procedure
Average patient age74

Dollar amounts are not shown. What Medicare pays a practice is gross billings, before staff, premises and tax and including the cost of any drugs it administers, so it is not what a clinician earns.

Practises at

Facilities the CMS Facility Affiliation file lists for this clinician.

Colleagues at UCSF Medical Group Business Services

Clinicians the CMS Doctors & Clinicians file lists under the same group practice. CMS counts 1531 clinicians in the practice; 12 are shown here.

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