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Hematology/Oncology

Gabriela S. Hobbs, MD

Works at hospitals in Boston, MA · Newton, MA · Northampton, MA … · Massachusetts, New Hampshire

Summary

Dr. Gabriela S. Hobbs, MD is a hematologist-oncologist at 40 2nd Ave, Waltham, MA 02451. Phone: (781) 487-2900. Accepts Medicare assignment. In 2024, Gabriela S. Hobbs had 207 Original Medicare patients and 957 services. NPI 1285893453. Source: CMS National Downloadable File, updated October 2, 2026; CMS Facility Affiliation Data, updated October 2, 2026; CMS Medicare Physician & Other Practitioners, data year 2024.

From official Medicare data

This page shows what Medicare's official clinician data says about Gabriela S. Hobbs, 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 Gabriela S. Hobbs accept Medicare assignment?
Yes. Medicare's clinician data says Gabriela S. Hobbs 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.
How many Medicare patients does Gabriela S. Hobbs see?
In 2024, CMS data shows 207 Original Medicare patients and 957 services for Gabriela S. Hobbs. This counts Original Medicare only and measures volume, not quality.
What is Gabriela S. Hobbs's NPI number?
1285893453. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Medicare activity in 2024

Official CMS public-use data for Gabriela S. Hobbs, data year 2024 (released May 21, 2026). It covers Original Medicare (fee-for-service) patients only, not Medicare Advantage or other insurance. It shows volume, not quality or outcomes. CMS hides any count of 10 or fewer patients.

Original Medicare patients207
Services billed to Medicare957
Different services or procedures9
Participating Medicare providerYes
Average age of these patients75

Most frequent services

  1. Established patient office or other outpatient visit with moderate level of decision making, if using time, 30 minutes or more (99214)332 services
  2. Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes (99233)283 services
  3. Visit complexity inherent to evaluation and management associated with medical care services that serve as the continuing focal point for all needed health care services and/or with medical care services that are part of ongoing care related to a patient's (G2211)240 services
  4. Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more (99215)32 services
  5. Initial hospital care with moderate level of medical decision making, if using time, at least 75 minutes (99223)19 services

Chronic conditions among these patients

Share of this clinician’s Original Medicare patients with each condition, as published by CMS (it describes the patients, not the care given).

  • High blood pressure71%
  • High cholesterol70%
  • Arthritis44%
  • Ischemic heart disease32%
  • Anxiety32%
  • Chronic kidney disease29%

Hospitals where Gabriela S. Hobbs works

Medicare's Facility Affiliation Data lists Gabriela S. Hobbs at these hospitals (updated October 2, 2026). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians. Star rating and emergency services: Hospital General Information (CMS), data updated October 26, 2026.

Practice locations

Addresses where Gabriela S. Hobbs is enrolled with Medicare (CMS data updated October 2, 2026).

Group practices

Medicare enrollment lists Gabriela S. Hobbs as a member of these groups (CMS data updated October 2, 2026).

  • Massachusetts General Physicians Organization Inc3,558 clinicians in the group
  • The General Hospital Corporation1,267 clinicians in the group

Specialties

Find other Hematology/Oncology doctors in Massachusetts →

Other hematologist-oncologists in Waltham

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

All hematologist-oncologists in Waltham →

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 schoolIcahn School Of Medicine At Mount Sinai
Graduation year2008 (18 years since medical school)
Gender (as listed)Female
Medicare assignmentAccepts (Medicare-approved amount as full payment)
TelehealthOffers telehealth services
NPI (National Provider Identifier)1285893453
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. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated October 2, 2026, retrieved October 29, 2026
  2. Hospital General Information — CMS, data updated October 26, 2026, retrieved November 13, 2026
  3. National Downloadable File (Doctors and Clinicians) — CMS, data updated October 2, 2026, retrieved October 29, 2026
  4. Medicare Physician & Other Practitioners - by Provider — CMS, data year 2024, released May 21, 2026; Medicare Physician & Other Practitioners - by Provider and Service
  5. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  6. Medicare Care Compare — official Medicare tool to look up clinicians