Alexander Tomas Adler Gregor, MD

Primary specialty

Student in an Organized Health Care Education/Training ProgramTaxonomy code 390200000X

License

339018 Issued in NY

Practice address

1275 York Avenue
Box 435
New York, NY 10065

Phone

(212) 639-7537

Fax

(416) 480-4225

NPI assigned

Apr 3, 2025

Sex

Male

Sole proprietor

No

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

Specialties & licenses 1

Addresses

Medicare fee-for-service enrollment

Not listed in the public Medicare enrollment file

Medicare enrollment (NPD)

Not enrolled

Credentials

Doctor of Medicine

State licenses

Practice roles

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.

• Memorial Sloan Kettering Cancer Center

  • Special Hospital
  • New York, NY
  • NPI 1821255365
  NPD (past)
• Memorial Sloan-Kettering Cancer Center

  • Special Hospital
  • New York, NY
  • NPI 1235394099
  NPD (past)

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

{
    "created_epoch": "1743638400000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1756252800000",
    "number": "1881498152",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "1275 YORK AVENUE",
            "address_2": "BOX 435",
            "city": "NEW YORK",
            "state": "NY",
            "postal_code": "10065",
            "telephone_number": "212-639-7537"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "1275 YORK AVENUE",
            "address_2": "BOX 435",
            "city": "NEW YORK",
            "state": "NY",
            "postal_code": "10065",
            "telephone_number": "212-639-7537",
            "fax_number": "416-480-4225"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "last_name": "GREGOR",
        "first_name": "ALEXANDER",
        "middle_name": "TOMAS ADLER",
        "credential": "MD",
        "sole_proprietor": "NO",
        "sex": "M",
        "enumeration_date": "2025-04-03",
        "last_updated": "2025-08-27",
        "certification_date": "2025-08-27",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "390200000X",
            "taxonomy_group": "",
            "desc": "Student in an Organized Health Care Education/Training Program",
            "state": "NY",
            "license": "339018",
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Bryce Wyndham Gregg, RN
• Isabel Amanda Gregg, N.P.
• Stacy Gregg
• Stephanie Gregg
• Elvira Gregoire
• Courtney Anne Gregor, LMSW
• Adrienne Elise Gregorek, PT, DPT
• Kaitlyn Gregorio
• Maria Gregorio, LCSW
• Olivia Gregorio

• Student in an Organized Health Care Education/Training Program in New York, NY
• Providers in New York, NY by specialty
• Student in an Organized Health Care Education/Training Program in New York

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Aug 27, 2025; self-reported and not verified by CMS. Specialty names from the NUCC taxonomy.
• National Provider Directory (CMS): practice roles, locations, licenses, networks and endpoints.

Verify at the official NPI Registry.