Gregory S Sibley, M.D.

Primary specialty

Radiation Oncology PhysicianTaxonomy code 2085R0001X

License

0101052359 Issued in VA

Practice address

8613 Route 29 Ste 100N
Fairfax, VA 22031-2172

Phone

(571) 350-8400

Fax

(703) 280-9596

NPI assigned

Aug 9, 2005

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

Other identifiers 1

Electronic endpoints 1

Medicare fee-for-service enrollment

Enrolled in DC, VA2 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

Radiation Oncology

Education

University of Michigan Medical School, 1990

Medicare assignment

Accepts the Medicare-approved amount as payment in full

Telehealth

Offers telehealth services

Group practices

Virginia Cancer Specialists, P.C.Group PAC ID 2264412485, 80 clinicians

Practice addresses (Care Compare)

Medicare enrollment (NPD)

Enrolled

Credentials

Doctor of Medicine

State licenses

Practice roles

Interoperability endpoints

• Direct secure messaging: gregory.sibley@vcs.ikm.direct-ci.com

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.

• Virginia Cancer Specialists, P.C.

  • Hematology & Oncology Physician
  • Fairfax, VA
  • NPI 1346294519

  DC

  Medicare reassignment Care Compare group
• Frederick Health Hospital Inc

  • General Acute Care Hospital
  • Frederick, MD
  • NPI 1538165527
  NPD (past)
• Radiation Oncology Associates of Washington, PC

  • Specialist
  • Washington, DC
  • NPI 1265413850
  NPD (past)
• Windber Hospital, Inc.

  • General Acute Care Hospital
  • Windber, PA
  • NPI 1275620536
  NPD (past)

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

{
    "created_epoch": "1123545600000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1762819200000",
    "number": "1043211360",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "3040 WILLIAMS DR STE 100",
            "city": "FAIRFAX",
            "state": "VA",
            "postal_code": "220314618",
            "telephone_number": "571-350-8400",
            "fax_number": "703-280-9596"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "8613 ROUTE 29 STE 100N",
            "city": "FAIRFAX",
            "state": "VA",
            "postal_code": "220312172",
            "telephone_number": "571-350-8400",
            "fax_number": "703-280-9596"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "last_name": "SIBLEY",
        "first_name": "GREGORY",
        "middle_name": "S",
        "name_prefix": "Dr.",
        "credential": "M.D.",
        "sole_proprietor": "NO",
        "sex": "M",
        "enumeration_date": "2005-08-09",
        "last_updated": "2025-11-11",
        "certification_date": "2025-11-11",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "2085R0001X",
            "taxonomy_group": "",
            "desc": "Radiology, Radiation Oncology",
            "state": "VA",
            "license": "0101052359",
            "primary": true
        }
    ],
    "identifiers": [
        {
            "code": "05",
            "desc": "MEDICAID",
            "issuer": null,
            "identifier": "5821738",
            "state": "DC"
        }
    ],
    "endpoints": [
        {
            "endpointType": "DIRECT",
            "endpointTypeDescription": "Direct Messaging Address",
            "endpoint": "gregory.sibley@ikm.direct-ci.com",
            "affiliation": "N",
            "endpointDescription": "direct messaging for provider",
            "use": "DIRECT",
            "useDescription": "Direct",
            "contentType": "OTHER",
            "contentTypeDescription": "Other",
            "contentOtherDescription": "electronic health records",
            "address_1": "8613 Lee Hwy",
            "city": "Fairfax",
            "state": "VA",
            "country_code": "US",
            "postal_code": "220312171",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "other_names": []
}

• Randy Lee Shusman, LCSW
• Amelia Shuster
• Siavash Sobhani M.D. P.C.
• Hassan Sibay, M.D.
• David Paul Sibley, D.D.S.
• Lily Chu Sicard, M.D.
• Hannah Sichel, MS
• Humaira Adeeb Siddiqi, M.D.
• Ali Ahmed Siddiqui, MD
• Olivia Siddle

• Radiation Oncology Physician in Fairfax, VA
• Providers in Fairfax, VA by specialty
• Radiation Oncology Physician in Virginia

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Nov 11, 2025; 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.