Ron S Gejman, MD, PHD

Primary specialty

Medical Oncology PhysicianTaxonomy code 207RX0202X

License

323560 Issued in NY

Practice address

177 Fort Washington Ave
MHB 6GN-435
New York, NY 10032-3733

Phone

(212) 305-8923

NPI assigned

Mar 21, 2020

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 NY

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

Medical Oncology

Education

Other, 2020

Medicare assignment

Accepts the Medicare-approved amount as payment in full

Telehealth

Offers telehealth services

Group practices

Trustees of Columbia University in the City of New YorkGroup PAC ID 8527972546, 2,262 clinicians

Practice addresses (Care Compare)

Medicare enrollment (NPD)

Enrolled

Credentials

Doctor of Medicine, Doctor of Philosophy

State licenses

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.

• Trustees of Columbia University in the City of New York

  • Surgery Physician
  • New York, NY
  • NPI 1508266347
  Medicare reassignment Care Compare group

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

{
    "created_epoch": "1584748800000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1777507200000",
    "number": "1811523848",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "177 FORT WASHINGTON AVE",
            "address_2": "MHB 6GN-435",
            "city": "NEW YORK",
            "state": "NY",
            "postal_code": "10032",
            "telephone_number": "212-305-8923"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "177 FORT WASHINGTON AVE",
            "address_2": "MHB 6GN-435",
            "city": "NEW YORK",
            "state": "NY",
            "postal_code": "100323733",
            "telephone_number": "212-305-8923"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "last_name": "GEJMAN",
        "first_name": "RON",
        "middle_name": "S",
        "name_prefix": "Dr.",
        "credential": "MD, PHD",
        "sole_proprietor": "YES",
        "sex": "M",
        "enumeration_date": "2020-03-21",
        "last_updated": "2026-04-30",
        "certification_date": "2026-04-30",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "207R00000X",
            "taxonomy_group": "",
            "desc": "Internal Medicine",
            "state": "NY",
            "license": "323560",
            "primary": false
        },
        {
            "code": "207RX0202X",
            "taxonomy_group": "",
            "desc": "Internal Medicine, Medical Oncology",
            "state": "NY",
            "license": "323560",
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Kelly Geisler, PSY.D
• Stephen H Geisler, MD
• Richard Geismar, PT
• Audrey Geist
• Elise Marie Geithner, NP
• Dmitriy Gekhman, MD
• Biana Gekht, OD
• Gelb Rejuvenation Dentistry, PLLC
• Bruce Gelb, M.D.
• Bruce Elliot Gelb, M.D.

• Medical Oncology Physician in New York, NY
• Providers in New York, NY by specialty
• Medical Oncology Physician in New York

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Apr 30, 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.