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Pediatric Medicine

Stephen T. Nishiyama, MD

Sees patients in Boston, MA · Massachusetts

Summary

Dr. Stephen T. Nishiyama, MD is a pediatrician at 55 Fruit St, Boston, MA 02114. Phone: (617) 724-0287. Accepts Medicare assignment. NPI 1710978622. Source: CMS National Downloadable File, updated October 2, 2026.

  • Specialty: Pediatrician (Medicare lists Pediatric Medicine)
  • Address: 55 Fruit St, Boston, MA 02114 · Directions
  • Phone: (617) 724‑0287
  • Medicare: Accepts Medicare assignment
  • Group practice: Massachusetts General Physicians Organization Inc
  • Medical school: University Of Vermont College Of Medicine · graduated 1991 (35 years since medical school)
  • Gender (as listed): Male

From official Medicare data

This page shows what Medicare's official clinician data says about Stephen T. Nishiyama, joined by NPI number (data updated October 2, 2026). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

Quick answers

Does Stephen T. Nishiyama accept Medicare assignment?
Yes. Medicare's clinician data says Stephen T. Nishiyama accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of October 2, 2026. Ask the office to confirm before your visit.
What is Stephen T. Nishiyama's NPI number?
1710978622. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Practice locations

Addresses where Stephen T. Nishiyama is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Stephen T. Nishiyama as a member of this group (CMS data updated October 2, 2026).

  • Massachusetts General Physicians Organization Inc3,558 clinicians in the group

Specialties

Find other Pediatric Medicine doctors in Massachusetts →

Other pediatricians in Boston

Clinicians with the same Medicare primary specialty in Boston, MA — not a recommendation.

All pediatricians in Boston →

Other clinicians in Massachusetts General Physicians Organization Inc

Medicare enrollment lists these clinicians in the same group practice — not a recommendation.

Clinician information

CredentialMD
Medical schoolUniversity Of Vermont College Of Medicine
Graduation year1991 (35 years since medical school)
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1710978622
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  2. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  3. Medicare Care Compare — official Medicare tool to look up clinicians