Croix Fossum, M.D.

Primary specialty

Radiation Oncology PhysicianTaxonomy code 2085R0001X

License

A159160 Issued in CA

Practice address

7901 Frost St
San Diego, CA 92123-2701

Phone

(858) 939-5010

Fax

(858) 939-5021

NPI assigned

Apr 28, 2017

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

Enrolled in CA

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

Radiation Oncology

Education

Mayo Medical School, 2017

Medicare assignment

Accepts the Medicare-approved amount as payment in full

Group practices

X-Ray Medical Group Radiation Oncology IncGroup PAC ID 2668443326, 8 clinicians

Practice addresses (Care Compare)

Hospital & facility affiliations

• Sharp Memorial Hospital Hospital, San Diego, CA, CCN 050100
• Grossmont Hospital Hospital, La Mesa, CA, CCN 050026

Medicare enrollment (NPD)

Enrolled

Credentials

Doctor of Medicine

State licenses

Practice roles

Locations

Networks

• BSC 65 PLUS INDIVIDUAL MAPD

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.

• X-Ray Medical Group Radiation Oncology Inc

  • Radiation Oncology Physician
  • La Mesa, CA
  • NPI 1790724565
  Medicare reassignment Care Compare group NPD
• Sharp Chula Vista Medical Center

  • Skilled Nursing Facility
  • Chula Vista, CA
  • NPI 1538142369
  NPD (past)

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

• Grossmont Hospital Corporation

  • General Acute Care Hospital
  • La Mesa, CA
  • NPI 1528041811
  Care Compare affiliation
• Sharp Memorial Hospital

  • Rehabilitation Hospital Unit
  • San Diego, CA
  • NPI 1114901352
  Care Compare affiliation
• Sharp Memorial Hospital

  • General Acute Care Hospital
  • San Diego, CA
  • NPI 1407839921
  Care Compare affiliation

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

{
    "created_epoch": "1493337600000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1771372800000",
    "number": "1104351006",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "PO BOX 509015",
            "address_2": "DEPT 338",
            "city": "SAN DIEGO",
            "state": "CA",
            "postal_code": "921509015"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "7901 FROST ST",
            "city": "SAN DIEGO",
            "state": "CA",
            "postal_code": "921232701",
            "telephone_number": "858-939-5010",
            "fax_number": "858-939-5021"
        }
    ],
    "practiceLocations": [
        {
            "address_1": "5555 Grossmont Center Dr",
            "address_purpose": "LOCATION",
            "city": "LA Mesa",
            "state": "CA",
            "postal_code": "919423019",
            "country_code": "US",
            "telephone_number": "619-740-4500",
            "fax_number": "619-740-8499",
            "country_name": "United States",
            "address_type": "DOM"
        },
        {
            "address_1": "769 Medical Center Ct",
            "address_purpose": "LOCATION",
            "city": "Chula Vista",
            "state": "CA",
            "postal_code": "919116602",
            "country_code": "US",
            "telephone_number": "619-502-5851",
            "fax_number": "619-502-5865",
            "country_name": "United States",
            "address_type": "DOM"
        }
    ],
    "basic": {
        "last_name": "FOSSUM",
        "first_name": "CROIX",
        "credential": "M.D.",
        "sole_proprietor": "NO",
        "sex": "M",
        "enumeration_date": "2017-04-28",
        "last_updated": "2026-02-18",
        "certification_date": "2026-02-18",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "2085R0001X",
            "taxonomy_group": "",
            "desc": "Radiology, Radiation Oncology",
            "state": "CA",
            "license": "A159160",
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Amy Fose, PTA
• Kelsey E Foshee
• Kimberly Ann Foskett, LCPC, LPPC
• Jennifer Lee Foss, M.A.
• Lois Fossing, LVN
• Alexandra Devon Foster
• Alexandria Rae Foster, DO
• Amber Foster
• Ashton Louise Foster, RN
• Brittany P Foster

• Radiation Oncology Physician in San Diego, CA
• Providers in San Diego, CA by specialty
• Radiation Oncology Physician in California

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on Feb 18, 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.