William Hikaru Matsui, M.D.

Primary specialty

Medical Oncology PhysicianTaxonomy code 207RX0202X

License

R6828 Issued in TX

Practice address

1515 Holcombe Blvd
Houston, TX 77030-4000

Phone

(713) 792-6161

NPI assigned

May 10, 2006

Last updated

May 13, 2026By the provider in NPPES

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 TX

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

University of California, San Francisco School of Medicine, 1995

Medicare assignment

Accepts the Medicare-approved amount as payment in full

Telehealth

Offers telehealth services

Group practices

Seton Family of DoctorsGroup PAC ID 0941333280, 785 clinicians

Physicians Referral ServiceGroup PAC ID 7911801410, 2,728 clinicians

The University of Texas at AustinGroup PAC ID 2668559436, 154 clinicians

Practice addresses (Care Compare)

Hospital & facility affiliations

• Ascension Seton Medical Center Austin Hospital, Austin, TX, CCN 450056
• University of Texas M D Anderson Cancer Center Hospital, Houston, TX, CCN 450076

Merit-based Incentive Payment System (MIPS)

Final score

79.35 of 100Reported as group

Quality

76.32

Improvement activities

40

Cost

74.57

Medicare enrollment (NPD)

Enrolled

Credentials

Doctor of Medicine

Practice roles

Locations

Interoperability endpoints

• Direct secure messaging: william.matsui.1@16041.direct.athenahealth.com

Organizations this provider is connected to: Medicare benefit reassignments (the organization bills Medicare for this provider’s services), Care Compare group memberships, National Provider Directory roles and organizations whose NPPES authorized official is this provider.

• University of Texas at Austin Dell Medical School

  dba UT Health Austin

  • General Practice Physician
  • Austin, TX
  • NPI 1073066239
  Medicare reassignment Care Compare group NPD
• Seton Family of Doctors

  • Neurological Surgery Physician
  • Austin, TX
  • NPI 1588997233
  Medicare reassignment Care Compare group NPD (past)
• Physicians Referral Service

  • Multi-Specialty Clinic/Center
  • Houston, TX
  • NPI 1073574810
  Medicare reassignment Care Compare group
• Seton Family of Doctors

  dba One Medical Group of Texas

  • Family Medicine Physician
  • Austin, TX
  • NPI 1225644065
  NPD
• Seton Family of Doctors

  dba Ascension Texas Imaging

  • Radiology Clinic/Center
  • Austin, TX
  • NPI 1275290694
  NPD
• University of Texas at Austin

  dba University of Texas at Austin Speech & Hearing Center

  • Audiologist
  • Austin, TX
  • NPI 1871522771
  NPD
• University of Texas at Austin Dell Medical School

  dba UT Health Austin Ambulatory Surgery Center

  • Ambulatory Surgical Clinic/Center
  • Austin, TX
  • NPI 1780218305
  NPD
• University Health Services

  dba Uiversity of Texas at Austin

  • Health Service Clinic/Center
  • Austin, TX
  • NPI 1740313337
  NPD (past)

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

• Ascension Seton

  dba Ascension Seton Medical Center Austin

  • General Acute Care Hospital
  • Austin, TX
  • NPI 1164526786
  Care Compare affiliation
• University of Texas M. D. Anderson Cancer Center

  • General Acute Care Hospital
  • Houston, TX
  • NPI 1174582050
  Care Compare affiliation

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

{
    "created_epoch": "1147219200000",
    "enumeration_type": "NPI-1",
    "last_updated_epoch": "1778630400000",
    "number": "1568411049",
    "addresses": [
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "MAILING",
            "address_type": "DOM",
            "address_1": "PO BOX 4439",
            "city": "HOUSTON",
            "state": "TX",
            "postal_code": "772104439",
            "telephone_number": "713-792-2991"
        },
        {
            "country_code": "US",
            "country_name": "United States",
            "address_purpose": "LOCATION",
            "address_type": "DOM",
            "address_1": "1515 HOLCOMBE BLVD",
            "city": "HOUSTON",
            "state": "TX",
            "postal_code": "770304000",
            "telephone_number": "713-792-6161"
        }
    ],
    "practiceLocations": [],
    "basic": {
        "last_name": "MATSUI",
        "first_name": "WILLIAM",
        "middle_name": "HIKARU",
        "credential": "M.D.",
        "sole_proprietor": "NO",
        "sex": "M",
        "enumeration_date": "2006-05-10",
        "last_updated": "2026-05-13",
        "certification_date": "2026-05-13",
        "status": "A"
    },
    "taxonomies": [
        {
            "code": "207RX0202X",
            "taxonomy_group": "",
            "desc": "Internal Medicine, Medical Oncology",
            "state": "TX",
            "license": "R6828",
            "primary": true
        }
    ],
    "identifiers": [],
    "endpoints": [],
    "other_names": []
}

• Leslie K. Matson, PA-C
• Taylor Ann Matson, PA-C
• Stavros Matsoukas, MD
• Madison Matsuda, MD
• Elizabeth Cotton Matsui, M.D.
• Ayaka Matsumura
• Ryoichi Matsunuma
• Takahiro Matsuo, MD
• Mary Karen Christine Matt, DDS
• Eduardo J Matta, MD

• Medical Oncology Physician in Houston, TX
• Providers in Houston, TX by specialty
• Medical Oncology Physician in Texas

• NPPES NPI Registry (CMS): identity, addresses, specialties, licenses, identifiers and endpoints. Last updated by the provider on May 13, 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.