Cesar M Castro, M.D., M.SC.

Primary specialty

Medical Oncology PhysicianTaxonomy code 207RX0202X

License

235484 Issued in MA

Practice address

185 Cambridge St FL 5
Boston, MA 02114-2790

Phone

(617) 726-2000

Fax

(617) 643-3244

NPI assigned

Jul 18, 2007

Sex

Male

Sole proprietor

Yes

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

Specialties & licenses 2

Addresses

Medicare fee-for-service enrollment

Enrolled in MA, NH2 enrollments

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 2

Specialty

Hematology/OncologyAlso: Internal Medicine

Education

University of California, San Francisco School of Medicine, 2005

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

Brigham and Womens Physicians Organization IncGroup PAC ID 3870405988, 2,931 clinicians

Practice addresses (Care Compare)

Hospital & facility affiliations

• Massachusetts General Hospital Hospital, Boston, MA, CCN 220071
• 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: castro.cesar.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.

• Brigham & Womens Physicians Organization Inc

  • Internal Medicine Physician
  • Boston, MA
  • NPI 1033535497
  Medicare reassignment Care Compare group NPD
• The General Hospital Corporation

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

  • Dermatology Physician
  • Boston, MA
  • NPI 1801874573
  Medicare reassignment Care Compare group
• Foundation Medical Partners Inc

  • Internal Medicine Physician
  • Nashua, NH
  • NPI 1033162037
  Medicare reassignment NPD
• Wentworth Douglass Physician Corporation

  • Magnetic Resonance Imaging Radiologic Technologist
  • Dover, NH
  • NPI 1447352430
  Medicare reassignment
• General Hospital Corp

  • General Acute Care Hospital
  • Boston, MA
  • NPI 1508390014
  NPD
• Foundation Medical Partners Inc.

  • Durable Medical Equipment & Medical Supplies
  • Amherst, NH
  • NPI 1679921472
  NPD
• Brigham and Womens Physicians Organization Inc

  • Diagnostic Radiology Physician
  • Boston, MA
  • NPI 1265464598
  NPD (past)

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

• Brigham & Womens Hospital, Inc.

  • General Acute Care Hospital
  • Boston, MA
  • NPI 1790717650
  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": "1184716800000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1770595200000",
    "number": "1184824112",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "55 FRUIT ST",
            "city": "BOSTON",
            "state": "MA",
            "postal_code": "021142621"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "185 CAMBRIDGE ST FL 5",
            "city": "BOSTON",
            "state": "MA",
            "postal_code": "021142790",
            "telephone_number": "617-726-2000",
            "fax_number": "617-643-3244"
        }
    ],
    "practiceLocations": [
        {
            "address_1": "75 Francis St",
            "address_purpose": "LOCATION",
            "city": "Boston",
            "state": "MA",
            "postal_code": "021156106",
            "country_code": "US",
            "telephone_number": "617-732-5500",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "basic": {
        "last_name": "CASTRO",
        "first_name": "CESAR",
        "middle_name": "M",
        "credential": "M.D., M.SC.",
        "sole_proprietor": "YES",
        "sex": "M",
        "enumeration_date": "2007-07-18",
        "last_updated": "2026-02-09",
        "certification_date": "2026-02-09",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "207RX0202X",
            "taxonomy_group": "",
            "desc": "Internal Medicine, Medical Oncology",
            "state": "MA",
            "license": "235484",
            "primary": true
        },
        {
            "code": "207R00000X",
            "taxonomy_group": "",
            "desc": "Internal Medicine",
            "state": "MA",
            "license": "235484",
            "primary": false
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Ilse Castro-Aragon, M.D.
• Cristina Michelle Castro-Rivera, MDPHD
• Alba Daniela Castro
• Alexander Domingo Castro
• Andrea Castro, DNAP, CRNA
• Daniel Adrian Castro
• Sara Castro, MD, MPH
• Elizabeth Frances Castronovo, AGNP-BC
• Ashley Caswell, BEHAVIORAL THERAPIST
• Jacob Robert Caswell, MSW

• Medical Oncology Physician in Boston, MA
• Providers in Boston, MA by specialty
• Medical Oncology Physician in Massachusetts

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Feb 9, 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.