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

Justin F Gainor, MD

Individual provider Internal Medicine Physician · NPI 1487813010

Justin F Gainor, MD is a Medical Oncology in Boston, Massachusetts. Graduated from Harvard Medical School in 2008, 18 years ago. Practices with The General Hospital Corporation, a 1,276-clinician group, accepts Medicare assignment and offers telehealth. Licensed in Massachusetts.

Years since qualifying
18
Trained at
Harvard Medical School
Licensed in
MA
In the registry since
2008
Specialties on file
2
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

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Practice location Partly verified

Some contact details are missing from the federal record.

Massachusetts General Hospital 55 Fruit St
Boston, MA 02114
Phone: (617) 726-2862
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Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Medical Oncology Physician (primary) Taxonomy 207RX0202X · Licence 245561 (MA)
Internal Medicine Physician Taxonomy 207R00000X · Licence L-236372 (MA)

Record details

NPI number1487813010
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedJune 9, 2008
Last updated in NPPESJuly 29, 2013

Medicare enrollment

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

Medicare specialtyMEDICAL ONCOLOGY
Also practisesHEMATOLOGY, INTERNAL MEDICINE
Medical schoolHARVARD MEDICAL SCHOOL
Graduated 2008 (18 years in practice)
Group practice The General Hospital Corporation — 1276 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services
Practice locations3 on file with Medicare

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