Samuel Jacob Klempner, M.D

Primary specialty

Hematology & Oncology PhysicianTaxonomy code 207RH0003X

License

A125171 Issued in CA

Practice address

55 Fruit St
Boston, MA 02114-2696

Phone

(617) 724-7168

NPI assigned

Jul 24, 2007

Sex

Male

Sole proprietor

No

Registry information is reported by the provider to CMS and is not verified. About this source

Specialties & licenses 4

Addresses

Medicare fee-for-service enrollment

Enrolled in MA

Eligible to order & refer

• Part B services: Yes
• Medical equipment: Yes
• Home health: Yes
• Power mobility devices: Yes
• Hospice: Yes

Green means eligible to order or refer.

Enrollment records 1

Specialty

Hematology/OncologyAlso: Internal Medicine

Education

University of Massachusetts Medical School, 2007

Medicare assignment

Accepts the Medicare-approved amount as payment in full

Telehealth

Offers telehealth services

Group practices

The General Hospital CorporationGroup PAC ID 6507803806, 1,275 clinicians

Massachusetts General Physicians Organization IncGroup PAC ID 2466365820, 3,494 clinicians

Practice addresses (Care Compare)

Hospital & facility affiliations

• Mass General Brigham Home Care, Inc Home health agency, Newton, MA, CCN 227207
• Massachusetts General Hospital Hospital, Boston, MA, CCN 220071
• North Shore Medical Center - Hospital, Salem, MA, CCN 220035
• Newton-Wellesley Hospital Hospital, Newton, MA, CCN 220101
• Brigham and Women'S Hospital Hospital, Boston, MA, CCN 220110

Medicare enrollment (NPD)

Enrolled

Credentials

Doctor of Medicine

State licenses

Practice roles

Locations

Interoperability endpoints

• Direct secure messaging: klempner.samuel.mgh@direct.partners.masshiway.net

Organizations this provider is connected to: Medicare benefit reassignments (the organization bills Medicare for this provider’s services), Care Compare group memberships and National Provider Directory roles.

• Massachusetts General Physicians Organization Inc

  • Dermatology Physician
  • Boston, MA
  • NPI 1801874573

  Internal Medicine

  Medicare reassignment Care Compare group NPD
• The General Hospital Corporation

  • General Acute Care Hospital
  • Boston, MA
  • NPI 1023049236
  Medicare reassignment Care Compare group NPD
• Brigham & Womens Physicians Organization Inc

  • Internal Medicine Physician
  • Boston, MA
  • NPI 1033535497
  Medicare reassignment NPD
• General Hospital Corp

  • General Acute Care Hospital
  • Boston, MA
  • NPI 1508390014
  NPD
• Brigham and Womens Physicians Organization Inc

  • Diagnostic Radiology Physician
  • Boston, MA
  • NPI 1265464598
  NPD (past)
• Brigham and Womens Physicians Organization Inc

  • Diagnostic Radiology Physician
  • Jamaica Plain, MA
  • NPI 1578549507
  NPD (past)
• Bristol Park Medical Group, Inc

  • Family Medicine Physician
  • Costa Mesa, CA
  • NPI 1043266760

  Internal Medicine

  NPD (past)
• Cedars-Sinai Medical Center

  • General Acute Care Hospital
  • Los Angeles, CA
  • NPI 1639172372
  NPD (past)
• University of California Irvine

  • General Acute Care Hospital
  • Orange, CA
  • NPI 1689608150
  NPD (past)

Hospitals and other facilities this clinician is affiliated with according to Medicare Care Compare.

• Mass General Brigham Home Care, Inc.

  • Home Health Agency
  • Newton, MA
  • NPI 1083644017
  Care Compare affiliation Name & address match
• Brigham & Womens Hospital, Inc.

  • General Acute Care Hospital
  • Boston, MA
  • NPI 1790717650
  Care Compare affiliation
• Newton-Wellesley Hospital

  • General Acute Care Hospital
  • Newton, MA
  • NPI 1992737761
  Care Compare affiliation
• North Shore Medical Center, Inc.

  • General Acute Care Hospital
  • Salem, MA
  • NPI 1730121633
  Care Compare affiliation
• The General Hospital Corporation

  • General Acute Care Hospital
  • Boston, MA
  • NPI 1023049236
  Care Compare affiliation

The complete NPPES record for this NPI in the NPI Registry API format.

{
    "created_epoch": "1185235200000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1786665600000",
    "number": "1134329378",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "6424 COLGATE AVE",
            "city": "LOS ANGELES",
            "state": "CA",
            "postal_code": "900484409",
            "telephone_number": "508-954-6022"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "55 FRUIT ST",
            "city": "BOSTON",
            "state": "MA",
            "postal_code": "021142696",
            "telephone_number": "617-724-7168"
        }
    ],
    "practiceLocations": [
        {
            "address_1": "11800 Wilshire Blvd",
            "address_purpose": "LOCATION",
            "city": "Los Angeles",
            "state": "CA",
            "postal_code": "900256602",
            "country_code": "US",
            "telephone_number": "310-231-2167",
            "fax_number": "310-231-2172",
            "country_name": "United States",
            "address_type": "DOM"
        },
        {
            "address_1": "75 Francis St",
            "address_purpose": "LOCATION",
            "city": "Boston",
            "state": "MA",
            "postal_code": "021156110",
            "country_code": "US",
            "telephone_number": "617-732-5500",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "basic": {
        "last_name": "KLEMPNER",
        "first_name": "SAMUEL",
        "middle_name": "JACOB",
        "credential": "M.D",
        "sole_proprietor": "NO",
        "sex": "M",
        "enumeration_date": "2007-07-24",
        "last_updated": "2026-08-14",
        "certification_date": "2026-08-14",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "207R00000X",
            "taxonomy_group": "",
            "desc": "Internal Medicine",
            "state": "MA",
            "license": "232414",
            "primary": false
        },
        {
            "code": "207RH0003X",
            "taxonomy_group": "",
            "desc": "Internal Medicine, Hematology & Oncology",
            "state": "CA",
            "license": "A125171",
            "primary": true
        },
        {
            "code": "207RH0000X",
            "taxonomy_group": "",
            "desc": "Internal Medicine, Hematology",
            "state": "MA",
            "license": "243585",
            "primary": false
        },
        {
            "code": "207RX0202X",
            "taxonomy_group": "",
            "desc": "Internal Medicine, Medical Oncology",
            "state": "MA",
            "license": "243585",
            "primary": false
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Ronald Ellis Kleinman, MD
• Katheryn Kleitsas
• Giannoula Lakka Klement, MD
• Jennifer Ann Klemm, N.P.
• Meaghan Klempa, PA-C
• Maxine Madans Klenicki, MSW
• Veronica E Klepeis, MD, PHD
• Stephen Daniel Klepfer
• Sarah Kler
• Elizabeth Beryl Klerman, MD PHD

• Hematology & Oncology Physician in Boston, MA
• Providers in Boston, MA by specialty
• Hematology & Oncology Physician in Massachusetts

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Aug 14, 2026; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
• Medicare enrollment (CMS PECOS): enrollments, PAC IDs and benefit reassignments; Order and Referring.
• Medicare Care Compare (CMS): clinician profile, group practices, facility affiliations, MIPS scores and star ratings.
• National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.