2026 NPPES data Hematology & Oncology Physician NPI 1881606622 M.D.
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MARY ANNE FENTON, M.D.

Hematology & Oncology Physician in PROVIDENCE, Rhode Island. CMS National Plan and Provider Enumeration System profile including specialty classification, practice address, and Medicare prescribing data when reported.

Federal data — no proprietary rating. PlainDoctor publishes the actual CMS NPPES and Medicare records — NPI registration, specialty, practice location, and prescribing data — without a composite score or editorial opinion on top. Every field traces to a federal source.
Prescribing volume
790
Medicare Part D claims · 176 beneficiaries · Hematology & Oncology Physician avg: 847
Generic prescribing
92%
generic claims · 8% brand-name · higher generic rates reduce patient out-of-pocket costs
What the federal data reveals: MARY ANNE FENTON, M.D. is a Hematology & Oncology Physician ([object Object]) practicing in PROVIDENCE, Rhode Island with a Medicare Part D prescribing footprint of 790 claims across 176 beneficiaries — 8% brand-name prescribing .

What stands out: MARY ANNE FENTON, M.D. filed 790 Medicare Part D claims in 2023 across PROVIDENCE, Rhode Island. Every figure on this page comes straight from federal CMS records, with no proprietary rating applied.

Board certification likely (heuristic — not verified)

MARY ANNE FENTON, M.D. practices in an ABMS-board-eligible specialty and shows active CMS Medicare participation + 1 hospital affiliation — signals consistent with board-certified status. For verified board certification, see CertificationMatters.org (the official ABMS public lookup).

MARY ANNE FENTON, M.D. at a glance

Quality data not reported

NPI registry status

Active

Issued 08/12/2006

NPI 1881606622

Primary specialty

Hematology & Oncology Physician

Mid-sized

11,215 US NPIs in this specialty

Medicare Part D claims

790 7% vs specialty avg

2023 prescription claims

Specialty avg: 847

Specialty distribution in Rhode Island

How Hematology & Oncology Physician compares to other specialties among Rhode Island providers

Rhode Island providers

Hematology & Oncology Physician share within Rhode Island

1. Hematology & Oncology Physician42%2. Internal medicine21%3. Family medicine17%4. Surgical12%5. Pediatric8%
Hematology & Oncology Physician share within Rhode Island

Specialty board-certification context

Estimated specialty board-certified rate — Hematology & Oncology Physician (ABMS / AOA reference)

Quality data not reported
Est. board-certified rate
78%
Hematology & Oncology Physician ABMS/AOA estimate

Est. board-certified rate (Hematology & Oncology Physician) — ABMS / AOA estimate

0%100%78%
Est. board-certified rate (Hematology & Oncology Physician) — ABMS / AOA estimate

The Merit-based Incentive Payment System (MIPS) scores providers 0–100 across four performance categories: Quality, Cost, Promoting Interoperability, and Improvement Activities, weighted under 42 CFR §414.1380. Reporting is voluntary for many small practices, so absence of a MIPS score is not a quality signal.

Board certification through an ABMS or AOA member board signals voluntary post-licensure examination plus continuous Maintenance of Certification cycles. Verify any individual provider's status through certificationmatters.org (ABMS) or osteopathic.org (AOA).

MARY ANNE FENTON, M.D. is a Hematology & Oncology Physician provider practicing in PROVIDENCE, Rhode Island, according to the CMS National Plan and Provider Enumeration System (NPPES). Credentials: M.D.. NPI: 1881606622. This profile includes practice location, specialty classification, and organizational affiliations from the CMS provider registry. Provider information is self-reported to CMS and updated monthly.

MARY ANNE FENTON, M.D. appears in the CMS NPPES registry as a Hematology & Oncology Physician provider holding M.D. credentials at 593 EDDY ST, PROVIDENCE, RI, 02903, with a listed phone of (401) 444-5391. NPI 1881606622 was issued on 08/12/2006. Because NPPES data is self-reported by the provider and refreshed monthly, the address, phone, and specialty reflect what FENTON most recently submitted to CMS rather than a vetted directory listing, which is why patients should always confirm the practice is still at this location before scheduling.

Medicare Part D records for calendar year 2023 show 790 prescription claims written by this provider, covering 176 Medicare beneficiaries and totaling roughly $777K in drug spend, split 8% brand-name and 92% generic by claim count, with an opioid prescribing rate of 1.8%. These figures capture only Medicare Part D — commercial insurance, Medicaid, and cash-pay prescriptions are not included, and any drug-beneficiary cell under 11 is suppressed by CMS for patient privacy.

Hematology & Oncology Physician is a mid-sized specialty nationwide, with 11,215 enrolled providers across 54 states and an average of 847 Part D claims per prescriber, so the context for interpreting these metrics differs meaningfully from a primary-care baseline. Important: PlainDoctor is a directory of publicly available government data, not medical advice, a malpractice database, or a quality rating. Inclusion here does not imply a recommendation, and absence of complaints or sanctions on this page does not mean none exist — always verify credentials through the NPPES NPI Registry, your state medical board, and the ABMS or AOA before making healthcare decisions.

Practice Address

593 EDDY ST
PROVIDENCE, RI 02903

Provider Details

NPI 1881606622
Specialty Hematology & Oncology Physician
Credentials M.D.
Gender Female
NPI Issued 08/12/2006

Hospital and facility affiliations

Facilities where MARY ANNE FENTON, M.D. bills Medicare from. Star ratings (1-5) are CMS Hospital Compare's "Hospital overall rating" — a composite of mortality, readmission, patient experience, safety, timely care, and efficient use of medical imaging measures. Source: CMS Care Compare.

RHODE ISLAND HOSPITAL
★★★★☆ 4/5
EAST GREENWICH, RI
Acute Care Hospitals
CMS CCN: 410007

Affiliations sourced from CMS Doctors and Clinicians National Downloadable File; hospital ratings from CMS Hospital General Information dataset (cross-referenced by facility name + state).

Brand vs generic prescribing mix · Generic-heavy

MARY ANNE FENTON, M.D. — brand share 8.0%
Specialty average (est.)

8% brand-name claims vs 92% generic, on 790 2023 Medicare Part D claims.

The federal Medicare Part D Generic Dispensing Rate national benchmark sits near 90% generic / 10% brand for primary-care prescribers, per CMS Office of the Actuary 2024 estimates. Higher brand share is common in specialty prescribing where generic equivalents are not available.

Medicare Part D Prescribing Data

CMS Medicare Part D prescriber-level data for calendar year 2023.

790
Total Claims
$777K
Total Drug Cost
176
Medicare Beneficiaries

Prescribing Breakdown

30-Day Fills
1,587
Total Day Supply
45,767
Brand vs Generic
8% brand / 92% generic
Brand Drug Cost
$726K
Generic Drug Cost
$51K
Opioid Claims
14 (1.8% rate)

Patient Demographics

Average Patient Age
73.8 years
Avg HCC Risk Score
1.52
Gender Split
100% female / 0% male

Top Prescribed Drugs (Medicare Part D)

Top drugs by claim count for calendar year 2023. Based on Medicare Part D data only.

Drug Claims
Anastrozole
405
Letrozole
118
Exemestane
55
Tamoxifen Citrate
32
Dexamethasone
26
Ibrance
Palbociclib
24
Alendronate Sodium
20
Ondansetron Hcl
15
Eliquis
Apixaban
14
Oxycodone Hcl
12

* Counts below 11 are suppressed by CMS for patient privacy. Generic names shown where available from CMS Part D data.

Hematology & Oncology Physician Overview

How MARY ANNE FENTON, M.D. fits within the Hematology & Oncology Physician landscape nationally.

11,215
Hematology & Oncology Physician Providers in US
54
States with Hematology & Oncology Physician
847
Avg Claims per Provider

MARY ANNE FENTON, M.D.'s 790 claims are below the specialty average of 847.

Nearby Hematology & Oncology Physician Providers in Rhode Island

Other clinicians with the same primary specialty enrolled in Rhode Island, drawn from the same CMS NPPES roster as FENTON.

Compare Hematology & Oncology Physician nationally: see state-by-state distribution →

Frequently Asked Questions

What is MARY ANNE FENTON, M.D.'s specialty?
MARY ANNE FENTON, M.D. specializes in Hematology & Oncology Physician and practices in PROVIDENCE, Rhode Island. Credentials: M.D..
How much does MARY ANNE FENTON, M.D. prescribe under Medicare Part D?
In 2023, MARY ANNE FENTON, M.D. wrote 790 Medicare Part D claims totaling $777K in drug costs for 176 beneficiaries.
Where is MARY ANNE FENTON, M.D. located?
MARY ANNE FENTON, M.D. is located at 593 EDDY ST, PROVIDENCE, RI, 02903. Phone: (401) 444-5391.
What is MARY ANNE FENTON, M.D.'s NPI number?
MARY ANNE FENTON, M.D.'s National Provider Identifier (NPI) is 1881606622, issued on 08/12/2006.
Does MARY ANNE FENTON, M.D. prescribe more brand-name or generic drugs?
MARY ANNE FENTON, M.D.'s prescribing is 8% brand-name and 92% generic drugs by claim count, with $726K in brand drug costs.
Does MARY ANNE FENTON, M.D. prescribe opioids?
Yes, MARY ANNE FENTON, M.D. had 14 opioid claims in 2023 with an opioid prescribing rate of 1.8%.
How many Hematology & Oncology Physician providers are there in the US?
There are 11,215 Hematology & Oncology Physician providers across 54 states in the US. The average Hematology & Oncology Physician provider writes 847 Medicare Part D claims per year.
What drugs does MARY ANNE FENTON, M.D. prescribe most often?
Based on 2023 Medicare Part D data, MARY ANNE FENTON, M.D.'s most frequently prescribed drugs include Anastrozole, Letrozole, Exemestane. This reflects Medicare Part D prescriptions only and does not include commercial insurance or other payer types.
Does MARY ANNE FENTON, M.D. accept Medicare?
MARY ANNE FENTON, M.D. appears in CMS Medicare data with 790 Part D claims and 176 Medicare beneficiaries in 2023. Contact the provider's office directly to confirm current Medicare enrollment and accepted plans.
How can I verify MARY ANNE FENTON, M.D.'s credentials?
MARY ANNE FENTON, M.D.'s NPI is 1881606622 with credentials M.D.. You can verify this through the NPPES NPI Registry, check state medical board records, and confirm board certification through the ABMS or AOA.

Data Sources

Provider Directory
CMS National Plan and Provider Enumeration System (NPPES), download.cms.gov/nppes, updated monthly. Contains NPI, specialty, credentials, and practice location.
Specialty Classification
NUCC Health Care Provider Taxonomy (nucc.org), the industry standard for classifying provider specialties in Medicare and Medicaid billing.
Prescribing Data
CMS Medicare Part D Prescriber Public Use File (2023). Includes claims, drug costs, beneficiaries, and opioid prescribing rates.
Limitations
Provider data is self-reported to CMS. Prescribing data reflects Medicare Part D only and does not include commercial insurance, Medicaid, or cash prescriptions. Claims below 11 beneficiaries are suppressed by CMS for privacy.

See our complete data methodology for details on how we collect and process government data.

Data as of April 2026 (NPPES) / 2023 (Medicare Part D). Source: Centers for Medicare & Medicaid Services (CMS).

Disclaimer: Data from CMS NPPES and Medicare Part D. PlainDoctor does not rate or rank providers. Provider information is self-reported and may not be current. Always verify information directly with the provider. About · Methodology