JOHN ROSS CLARK
NPI 1871550244
Internal Medicine - Hematology & Oncology in Boston, MA

Q: What is John Clark's NPI number?

The NPI number for John Clark is 1871550244. It was assigned to this individual provider in the NPPES registry on April 28, 2006.

Q: What is John Clark's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Hematology & Oncology, with taxonomy code 207RH0003X.

Q: When was this NPI record last updated?

The NPPES record for John Clark was last updated on January 16, 2013. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 13 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.

Active since April 28, 2006PECOS Enrolled

55 FRUIT STREET, YAW 7B MASS GENERAL HOSPITAL, BOSTON, MA 02114(617) 724-4000(617) 643-1915 Get Directions Write a Review

NPPES record last updated: January 16, 2013. Verified against the NPPES registry weekly; last sync: August 16, 2026.

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About John Ross Clark NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

JOHN ROSS CLARK (NPI 1871550244) is an individual hematology & oncology provider in Boston, Massachusetts, licensed in Massachusetts (49154) and active in the NPI registry since April 2006. He is enrolled in Medicare PECOS.

NPPES Registry Identity

NPI1871550244

Entity TypeIndividualMale

Primary Taxonomy207RH0003X

Provider Legal NameJOHN ROSS CLARK

Location Address55 FRUIT STREET, YAW 7B MASS GENERAL HOSPITALBoston, MA 02114-2696

Mailing AddressPo Box 9142, Mass General Physicians Organization IncCharlestown, MA 02129-9142 · (617) 724-4000 · Fax (617) 643-1915

Phone(617) 724-4000

Fax(617) 643-1915

Sole ProprietorNo

Enumeration DateApril 28, 2006

Last NPPES UpdateJanuary 16, 2013

✔ NPI 1871550244 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyInternal Medicine · Hematology & OncologyAllopathic & Osteopathic Physicians

Taxonomy Code207RH0003X

License✔ Licensed in MA · 49154

Definition

An internist doctor of osteopathy that specializes in the treatment of the combination of hematology and oncology disorders. A doctor of osteopathy that is board eligible/certified by the American Osteopathic Board of Internal Medicine WAS able to obtain a Certificate of Special Qualifications in the field of Hematology and Oncology. The Certificate is NO longer offered.

55 FRUIT STREET, Boston, MA 02114

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Other Identifiers 4

Medicare UPINB76538

OtherJ02760Blue Cross Blue Shield

Medicare PINJ02760MA

Medicaid6194613MA

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

✔

Enrolled in Medicare (PECOS)

John Ross Clark is registered in the CMS Provider Enrollment, Chain and Ownership System (PECOS).

Eligible to Order & Refer✔ Part B Labs & Imaging✔ Durable Medical Equipment✔ Home Health Agency✔ Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 02114 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient

$189.86 typical visit price

range $63.72 – $189.86

Typical copayment $47.46 (range $15.93 – $47.46)

Most-billed visit code 99205

Established Patient

$111.18 typical visit price

range $21.07 – $155.29

Typical copayment $27.79 (range $5.26 – $38.82)

Most-billed visit code 99214

Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Referred Medical Equipment & Supplies CMS DME claims

Durable medical equipment, devices and supplies this provider ordered from DME suppliers for patients, from Medicare fee-for-service claims.

Enteral formula, nutritionally complete with intact nutrients, includes proteins, fats, carbohydrates, vitamins and minerals, may include fiber, administered through an enteral feeding tube, 100 calories = 1 unit B4150

Other-Enteral and Parenteral · category OB006N

1 supplier12 claims4,290 services$0.29 avg. paid by Medicare

Dollar amounts are the average Medicare paid the supplier per service. They are not the cost to the patient.

Other Providers at the Same Location NPPES 20

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

KUI TOH GERARD LEONG M.D.

Internal Medicine (Cardiovascular Disease)

55 FRUIT STREET, MASSACHUSETTS GENERAL HOSPITAL
BOSTON, MA 02114

Suffolk County (617) 726-8862

MS. JACQUELINE BANGO LICSW

Social Worker (Clinical)

55 FRUIT STREET, FOUNDERS BUILDING SUITE 880
BOSTON, MA 02114

Suffolk County (617) 643-8281

SARA ELIZABETH GROSSLEIN PA

Physician Assistant

55 FRUIT STREET, WHITE 1
BOSTON, MA 02114

Suffolk County (617) 724-4100

JEFFREY M ELLENBOGEN M.D.

Psychiatry & Neurology (Neurology)

55 FRUIT STREET, WANG 720 (NEUROLOGY)
BOSTON, MA 02114

Suffolk County (617) 724-7419

DR. NANCY LEE HARRIS MD

Pathology (Anatomic Pathology & Clinical Pathology)

55 FRUIT STREET, WRN 2 PATHOLOGY ASSOCIATES
BOSTON, MA 02114

Suffolk County (617) 726-5155

DR. STANLEY YANG SHAW MD PHD

Internal Medicine (Cardiovascular Disease)

55 FRUIT STREET, YAW 5 CARDIAC UNIT ASSOCIATES
BOSTON, MA 02114

Suffolk County (617) 724-6750

LEONARDO V RIELLA M.D., PHD

Internal Medicine

55 FRUIT STREET, WHITE 5
BOSTON, MA 02114

Suffolk County (617) 726-5050

SUSAN MAHER CRNA

Nurse Anesthetist, Certified Registered

55 FRUIT STREET, CLN 309 MGH ANESTHESIA ASSOCIATES
BOSTON, MA 02114

Suffolk County (617) 726-3030

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is John Clark's NPI number?

The NPI number for John Clark is 1871550244. It was assigned to this individual provider in the NPPES registry on April 28, 2006.

Where is John Clark located?

John Clark practices at 55 Fruit Street Yaw 7B Mass General Hospital, Boston, MA 02114. The listed phone number is (617) 724-4000.

What is John Clark's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Hematology & Oncology, with taxonomy code 207RH0003X.

Is John Clark enrolled in Medicare?

Yes. John Clark is registered in the Medicare PECOS enrollment system.

When was this NPI record last updated?

The NPPES record for John Clark was last updated on January 16, 2013. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 13 years ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.