DR. DIANE C. TSAI M.D.
NPI 1730266966
Radiology - Radiation Oncology in Portland, OR

Active since November 01, 2006PECOS EnrolledAccepts Medicare Assignment
3620 N INTERSTATE AVE, PORTLAND, OR 97227(503) 813-2000 Get Directions Write a Review

NPPES record last updated: December 9, 2025. Verified against the NPPES registry weekly; last sync: August 16, 2026.

Record update history: Dec 9, 2025, Sep 28, 2022, Sep 30, 2021 and 1 more (4 updates tracked since 2021).

About Dr. Diane C. Tsai M.d. NPPES

Official registry information on file with the National Plan and Provider Enumeration System.

DR. DIANE C. TSAI M.D. (NPI 1730266966) is an individual radiation oncology provider in Portland, Oregon, licensed in Oregon (MD174455) and active in the NPI registry since November 2006. She is enrolled in Medicare PECOS, is affiliated with Columbia Memorial Hospital, and is a graduate of Other (1991).

NPPES Registry Identity

NPI1730266966
Entity TypeIndividualFemale
Primary Taxonomy2085R0001X
Provider Legal NameDR. DIANE C. TSAICredential: M.D.
Location Address3620 N INTERSTATE AVEPortland, OR 97227-1106
Mailing Address500 Ne Multnomah St Ste 100Portland, OR 97232-2031 · (800) 813-2000 · Fax (855) 524-5255
Sole ProprietorNo
Medical School CMSOtherGraduated 1991
Enumeration DateNovember 1, 2006
Last NPPES UpdateDecember 9, 20254 updates tracked since enumeration
NPPES CertifiedDecember 9, 2025
NPI 1730266966 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

Primary SpecialtyRadiology · Radiation OncologyAllopathic & Osteopathic Physicians
Taxonomy Code2085R0001X
Licenses Licensed in OR · MD174455 Licensed in CA · G86931 Licensed in WA · MD00037303
Definition
A radiologist who deals with the therapeutic applications of radiant energy and its modifiers and the study and management of disease, especially malignant tumors.
3620 N INTERSTATE AVE, Portland, OR 97227

Accepted Insurance

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, and ordering and referring status from the CMS PECOS system.

Medicare Enrollment Status

Enrolled in Medicare and accepts Medicare assignment

Dr. Diane C. Tsai M.d. is registered in PECOS and agrees to accept the Medicare-approved amount as full payment. Medicare patients are not billed beyond the standard deductible and coinsurance.

PECOS PAC ID7315843521
PECOS Enrollment IDI20031209000735, I20151002002628, I20180702002294
Eligible to Order & Refer Part B Labs & Imaging Durable Medical Equipment Home Health Agency Power Mobility DevicesPer the CMS Ordering and Referring file. Eligibility means Medicare pays claims that this provider orders or refers for these categories.

Areas of Expertise CMS Part B claims 6

Services this provider delivered to Medicare fee-for-service patients, from the CMS Medicare utilization data. Higher counts generally reflect more experience with a service; care delivered outside Medicare is not included.

Continuing radiation therapy consultation per week 77336
Continuing radiation therapy consultation per week involves regular meetings with your healthcare team. These sessions help monitor your progress, manage side effects, and adjust your treatment plan if necessary. It's a key part of ensuring the effectiveness of your radiation therapy.
68 services14 patients
Radiation treatment management, 5 treatment sessions 77427
Radiation treatment management involves a series of 5 sessions where targeted radiation is used to destroy or shrink cancer cells in your body. Each session is carefully planned to maximize effectiveness while minimizing harm to healthy tissues. You may experience side effects which will be closely monitored and managed for your comfort.
63 services13 patients
Established patient office or other outpatient visit with low level od decision making, if using time, 20 minutes or more 99213
This is a routine visit for patients who have already been seen by the healthcare provider. During this approximately 20-29 minute appointment, your health status will be evaluated and any necessary treatments or tests will be discussed. It's a chance to address any health concerns you may have.
27 services25 patients
Prolonged office or other outpatient evaluation and management service(s) beyond the maximum required time of the primary procedure which has been selected using total time on the date of the primary service; each additional 15 minutes by the physician or G2212
This service refers to extended doctor visits where your healthcare provider spends additional time evaluating and managing your health beyond the primary procedure's required time. This includes each extra 15 minutes spent by the physician on the same day as the primary service.
27 services12 patients
Established patient office or other outpatient visit with high level of medical decision making, if using time, 40 minutes or more 99215
This service involves a follow-up appointment for existing patients, lasting between 40 to 54 minutes. During this time, your healthcare provider will assess your current health status, discuss any changes or concerns, review your treatment plan, and answer any questions you may have.
24 services19 patients
New patient office or other outpatient visit with a high level of medical decision making, if using time, 60 minutes or more 99205
This is a first-time patient visit where a healthcare professional spends 60-74 minutes with you. It involves a comprehensive evaluation, including your medical history and current health condition. They'll also advise on preventive health measures and formulate a treatment plan if needed.
14 services14 patients

Hospital Affiliations CMS Care Compare 2

Hospitals where this provider delivers care, identified from recent Medicare claims and place-of-service records.

Columbia Memorial Hospital

Critical Access Hospitals · Astoria, OR
OwnershipProprietary
CMS Certification Number381320
Location2111 Exchange StreetAstoria, OR 97103 · Clatsop County
Emergency services Birthing friendly

Providence St Mary Medical Center

Acute Care Hospitals · Walla Walla, WA
3/5 CMS rating
OwnershipVoluntary non-profit - Private
CMS Certification Number500002
Location401 W Poplar StWalla Walla, WA 99362 · Walla Walla County
Emergency services Birthing friendly

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 97227 ZIP code area, from fee-for-service claims. These are area statistics, not this provider’s prices; actual charges vary by service and coverage.

New Patient
$176.88 typical visit price
range $58.99 – $176.88
Typical copayment $44.22 (range $14.74 – $44.22)
Most-billed visit code 99205
Established Patient
$73.28 typical visit price
range $19.32 – $144.79
Typical copayment $18.32 (range $4.83 – $36.19)
Most-billed visit code 99213
Amounts reflect what Medicare beneficiaries in this ZIP area are typically charged for office visits. Patients with other coverage should check their individual plans.

Other Providers at the Same Location NPPES 8

Providers registered at the same practice address, or within the immediate area, according to the NPPES registry.

Radiology (Radiation Oncology)
3620 N INTERSTATE AVE
PORTLAND, OR 97227
Radiology (Radiation Oncology)
3620 N INTERSTATE AVE
PORTLAND, OR 97227
Radiology (Radiation Oncology)
3620 N INTERSTATE AVE
PORTLAND, OR 97227
Clinic/Center (Oncology, Radiation)
3620 N INTERSTATE AVE
PORTLAND, OR 97227
Radiology (Radiation Oncology)
3620 N INTERSTATE AVE
PORTLAND, OR 97227
Counselor
3620 N INTERSTATE AVE
PORTLAND, OR 97227
Nurse Practitioner (Family)
3620 N INTERSTATE AVE
PORTLAND, OR 97227
Internal Medicine
3620 N INTERSTATE AVE
PORTLAND, OR 97227

Frequently Asked Questions NPPES & CMS

Common questions about this NPI record, answered from the official NPPES registry and CMS datasets shown on this page.

What is Diane Tsai's NPI number?

The NPI number for Diane Tsai is 1730266966. It was assigned to this individual provider in the NPPES registry on November 1, 2006.

Where is Diane Tsai located?

Diane Tsai practices at 3620 N Interstate Ave, Portland, OR 97227. The listed phone number is (503) 813-2000.

What is Diane Tsai's specialty?

The primary specialty registered for this NPI is Radiology, specializing in Radiation Oncology, with taxonomy code 2085R0001X.

Is Diane Tsai enrolled in Medicare?

Yes. Diane Tsai is registered in the Medicare PECOS system and accepts Medicare assignment, which means accepting the Medicare-approved amount as payment in full for covered services.

What insurance does Diane Tsai accept?

Health plans from BridgeSpan Health Company, Kaiser Permanente, Moda Health Plan, Inc., PacificSource Health Plans and Premera Blue Cross Blue Shield of Alaska and 2 other insurers list Diane Tsai as in-network in at least one marketplace plan. Coverage varies by plan and year; verify with the insurer or the provider before a visit.

Is Diane Tsai affiliated with any hospitals?

According to CMS data, Diane Tsai is affiliated with Columbia Memorial Hospital and Providence St Mary Medical Center.

When was this NPI record last updated?

The NPPES record for Diane Tsai was last updated on December 9, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 8 months ago. If this record has changed at CMS more recently, you can request an on-demand re-check against the live CMS registry, directly from this page.