Individual provider

Katherine Tierney, M.D.

Gynecologic Oncology Physician Obstetrics & Gynecology Physician Medicare enrolled

Katherine Tierney, M.D. is a Gynecologic Oncology Physician in Los Angeles, CA, registered under NPI 1669702502. This provider registers 2 separate taxonomy codes, which usually means they practise across more than one recognised specialty.

Getting there

The practice address on file is 1516 SAN PABLO ST FL 3, Los Angeles, CA 90033. We have not yet mapped what surrounds this office — parking, transit, and nearby pharmacies are added as our data collection reaches each location.

1516 SAN PABLO ST FL 3, Los Angeles, CA 90033 Open in Google Maps →

Credentials and Medicare

State licence
LicenceStateSpecialty
A110278 CA Gynecologic Oncology Physician primary
A110278 CA Obstetrics & Gynecology Physician
MD60688841 WA Obstetrics & Gynecology Physician

Licences are recorded in 2 states: CA, WA. Providers licensed in several states often practise near a state border or deliver telehealth across state lines.

Medicare (PECOS)
Status
Approved
Provider type
Practitioner - Obstetrics/gynecology
PAC ID
9638323231

Enrolled in Medicare 3 times, across 3 states:

StateEnrollment IDProvider type
Washington I20161101002449 Practitioner - Obstetrics/gynecology
Oregon I20161101002609 Practitioner - Obstetrics/gynecology
California I20241105002220 Practitioner - Gynecological Oncology

Medicare enrolment is recorded as approved under the provider type Practitioner - Obstetrics/gynecology. There are 3 separate enrolment records across 3 states (WA, OR, CA). Multiple enrolments usually mean the provider bills Medicare from more than one practice location, or has kept an earlier enrolment after moving. Each record carries its own enrolment ID, listed above. Being enrolled means the provider can bill Medicare; it does not tell you whether they are currently accepting new Medicare patients. Call the office to confirm.

Licensed in 2 states

This provider holds licences in 2 states: California and Washington. The practice address on file is in Los Angeles, CA, but a licence in another state usually means they see patients there too — either at a second location or by telehealth. If the address above is far from you, it is worth calling to ask whether they practise closer to where you live.

CA California practice address
Licence
A110278
Specialty
Gynecologic Oncology Physician
Verify with the CA board →
WA Washington
Licence
MD60688841
Specialty
Obstetrics & Gynecology Physician
Verify with the WA board →

Licence numbers are self-reported to NPPES at registration. They do not confirm a licence is currently active, in good standing, or valid for the specialty shown — only the state board can tell you that, which is why we link to each one.

What Gynecologic Oncology covers

An obstetrician/gynecologist who provides consultation and comprehensive management of patients with gynecologic cancer, including those diagnostic and therapeutic procedures necessary for the total care of the patient with gynecologic cancer and resulting complications. NUCC Health Care Provider Taxonomy, code 207VX0201X
Allopathic & Osteopathic Physicians Obstetrics & Gynecology Gynecologic Oncology

All registered taxonomy codes

This provider registers 3 taxonomy codes. The primary code is what appears on most claims; the others record additional recognised specialties.

CodeSpecialtyLicenceState
207VX0201X Gynecologic Oncology Physician Gynecologic Oncology A110278 CA primary
207V00000X Obstetrics & Gynecology Physician A110278 CA
207V00000X Obstetrics & Gynecology Physician MD60688841 WA

The taxonomy records how the provider classifies their own practice. It does not confirm which conditions they currently treat, whether they are accepting new patients, or which insurance they take — call the office for that.

Full NPPES record

An NPI-1 identifies a single person. It stays with the clinician for life, even if they move practice or change state, which is why the address on file can lag behind where they actually work today.

NPI1669702502 valid check digit
Entity typeIndividual (NPI-1)
Enumeration dateDec 26, 2009
Last updatedFeb 13, 2025
StatusActive
Sole proprietorNo
CredentialM.D.
Practice address 1516 SAN PABLO ST FL 3
Los Angeles, CA 90033
(323) 276-3705
Mailing address PO BOX 31309
Los Angeles, CA 90031
This record was updated on Feb 13, 2025, which is recent enough that the contact details are likely still accurate.

Number check

1669702502 passes the NPI check digit test The final digit 2 matches the value computed from the first nine digits, so this is a well-formed NPI.
How the check works, step by step

Every NPI carries a Luhn check digit — the same scheme used on credit cards. CMS prefixes the number with 80840 before computing it, which marks it as a US health identifier.

Digit 8 0 8 4 0 1 6 6 9 7 0 2 5 0
Doubled? ×2 ×2 ×2 ×2 ×2 ×2 ×2
Value 8 0 8 8 0 2 6 3 9 5 0 4 5 0

Sum = 58 · next multiple of 10 = 60 · check digit = 2 · actual last digit = 2

A valid check digit only means the number is well-formed. It does not mean the provider is licensed, active, or in good standing — those are separate questions answered by the sections above.

Common questions

What is NPI number 1669702502?
NPI 1669702502 is the National Provider Identifier assigned to Katherine Tierney, M.D. in Los Angeles, CA. It is a 10-digit number issued by the Centers for Medicare & Medicaid Services and used on claims, referrals, and prescriptions to identify the provider.
What does Gynecologic Oncology cover?
An obstetrician/gynecologist who provides consultation and comprehensive management of patients with gynecologic cancer, including those diagnostic and therapeutic procedures necessary for the total care of the patient with gynecologic cancer and resulting complications.
How do I contact Katherine Tierney, M.D.?
The phone number on file with NPPES is (323) 276-3705, last updated Feb 13, 2025. Because NPPES is only updated when a provider files a change, call ahead to confirm the number and the current practice address before visiting.
Does Katherine Tierney, M.D. accept Medicare?
This NPI has an approved Medicare enrolment in PECOS, which means the provider is enrolled to bill Medicare. Enrolment does not guarantee they are accepting new Medicare patients — verify directly with the office.
Is NPI 1669702502 a valid number?
Yes. 1669702502 passes the Luhn check digit validation that CMS uses for NPI numbers, and it resolves to an active record in the registry.
How to use this page. Everything here comes from public federal records. Tips Health does not verify quality of care, confirm that a licence is currently active, or check malpractice history, and accepts no fees for placement. A listing is not a recommendation. Verify independently before seeking care.