DR. LIAM GHIAM MD, MS
NPI 1689123879
Radiology - Radiation Oncology in Los Alamitos, CA

Q: What is Liam Ghiam's NPI number?

The NPI number for Liam Ghiam is 1689123879. It was assigned to this individual provider in the NPPES registry on September 28, 2016. The provider is also known as Dr. Alireza Ghiam MD, Ms.

Q: What is Liam Ghiam's specialty?

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

Q: When was this NPI record last updated?

The NPPES record for Liam Ghiam was last updated on July 10, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 15 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.

Active since September 28, 2016PECOS EnrolledAccepts Medicare Assignment

3951 KATELLA AVE STE 102, LOS ALAMITOS, CA 90720(562) 799-3198(562) 799-3509 Get Directions Write a Review

NPPES record last updated: July 10, 2025. Verified against the NPPES registry weekly; last sync: October 18, 2026.

Record update history: Jul 10, 2025, May 12, 2025, Aug 15, 2023 and 9 more (12 updates tracked since 2016).

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About Dr. Liam Ghiam Md, Ms NPPES

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

DR. LIAM GHIAM MD, MS (NPI 1689123879) is an individual radiation oncology provider in Los Alamitos, California, licensed in California (A165739) and active in the NPI registry since September 2016. He is enrolled in Medicare PECOS and is a graduate of Other (2003).

NPPES Registry Identity

NPI1689123879

Entity TypeIndividualMale

Primary Taxonomy2085R0001X

Provider Legal NameDR. LIAM GHIAMCredential: MD, MS

Location Address3951 KATELLA AVE STE 102Los Alamitos, CA 90720-3303

Mailing Address3951 Katella Ave Ste 102Los Alamitos, CA 90720-3303 · (562) 799-3198 · Fax (562) 799-3509

Phone(562) 799-3198

Fax(562) 799-3509

Sole ProprietorNo

Medical School CMSOtherGraduated 2003

Enumeration DateSeptember 28, 2016

Last NPPES UpdateJuly 10, 202512 updates tracked since enumeration

NPPES CertifiedJuly 10, 2025

✔ NPI 1689123879 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses

★ Primary SpecialtyRadiology · Radiation OncologyAllopathic & Osteopathic Physicians

Taxonomy Code2085R0001X

License✔ Licensed in CA · A165739

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.

3951 KATELLA AVE STE 102, Los Alamitos, CA 90720

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Other Names 1

Professional Name (2)Dr. Alireza Ghiam Md, Ms

Medicare Participation & PECOS CMS

Medicare enrollment, assignment, billing reassignment, and ordering and referring status from CMS.

Medicare Enrollment Status

✔

Enrolled in Medicare and accepts Medicare assignment

Dr. Liam Ghiam Md, Ms 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 ID8729359864

PECOS Enrollment IDI20200210002780

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.

Medicare Billing Reassignments

Medicare enrollment records show Liam Ghiam reassigns Medicare billing to 2 organizations. Each organization bills Medicare for the services this provider delivers there; the nearest is listed first.

Uc Regents Department Of Radiation Oncology

10 mi

Radiation Oncology

101 THE CITY DR S
Orange, CA 92868

Reassigned Medicare billing, California enrollment
26 clinicians in this Medicare group

NPI 1386692473 (714) 456-8068

Usc Care Medical Group, Inc

20 mi

General Practice

1520 SAN PABLO ST
Los Angeles, CA 90033

Reassigned Medicare billing, California enrollment
2,445 clinicians in this Medicare group

NPI 1902846306 (323) 442-5955

Source: CMS Revalidation Reassignment List, October 2026 release. Reassignment records can lag staffing changes; confirm a current affiliation with the organization.

Areas of Expertise CMS Part B claims 15

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.

Stereoscopic x-ray guidance for localization of target volume for the delivery of radiation therapy G6002

Stereoscopic x-ray guidance is a technique used in radiation therapy. It involves taking multiple X-ray images from different angles to create a 3D picture of the area to be treated. This helps accurately pinpoint the exact location for radiation delivery, ensuring the therapy is as effective as possible.

1,300 services111 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.

296 services94 patients

Calculation of radiation therapy dose 77300

Radiation therapy dose calculation is a process to determine the exact amount of radiation needed to treat a specific area in the body. This calculation helps ensure the treatment is effective while minimizing harm to healthy tissues. It's a key part of planning your radiation therapy.

222 services70 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.

130 services99 patients

Design and construction of complex radiation treatment device 77334

The design and construction of a complex radiation treatment device is a process where a specialized instrument is created. This device targets harmful cells with high-energy rays to destroy or damage them, while minimizing impact on healthy cells. This aids in treating conditions like cancer.

126 services65 patients

Complex radiation therapy planning 77263

Complex radiation therapy planning is a process to determine the most effective way to deliver radiation to a specific area in your body. It involves detailed imaging to map your body's structure, allowing for precise targeting of cancer cells while sparing healthy tissue.

76 services70 patients

Design and construction of radiation treatment device for high precision radiation therapy 77338

A radiation treatment device is custom-made for each patient to target cancer cells with high precision. It's designed to focus radiation on the tumor, sparing healthy tissue. This process ensures effective therapy while minimizing side effects.

73 services57 patients

High precision radiation therapy planning 77301

High precision radiation therapy planning involves detailed mapping of your body to target cancer cells accurately. Advanced imaging techniques help identify the exact location of the tumor, minimizing harm to healthy tissues. This personalized approach enhances effectiveness and reduces side effects.

62 services57 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.

62 services62 patients

Special radiation treatment 77470

Special radiation treatment is a medical procedure that uses high-energy rays to destroy or damage cancer cells. It's a targeted approach that aims to minimize harm to healthy tissues. The treatment duration varies based on individual health conditions.

34 services32 patients

Obtaining data needed to develop the optimal radiation treatment, 1 treatment area 77280

This procedure involves gathering essential information to create the best radiation treatment plan for a specific area. It includes scanning the treatment area and using this data to calculate the precise dose of radiation needed to target the disease effectively, while sparing healthy tissue.

22 services21 patients

Obtaining respiratory data needed to develop the optimal radiation treatment 77293

Obtaining respiratory data is vital for optimal radiation treatment. This involves tracking your breathing patterns to ensure the precise delivery of radiation to the target area, minimizing damage to healthy tissue. It's a non-invasive process and contributes to effective treatment.

19 services18 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.

19 services15 patients

Obtaining data needed to develop the optimal radiation treatment, 3 or more treatment areas or any number of treatment areas where special treatment is involved 77290

This procedure involves collecting necessary data to plan the best radiation treatment. It may cover 3 or more areas or any area requiring special attention. Data collection includes imaging scans and tests to understand the disease's extent and to tailor a precise, effective treatment plan.

14 services13 patients

3d radiation therapy planning 77295

3D radiation therapy planning is a procedure that uses computer imaging to map out the area needing treatment. This ensures the radiation targets the disease precisely, while minimizing exposure to surrounding healthy tissues. It's a key step in preparing for effective radiation therapy.

13 services12 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 90720 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

$187.60 typical visit price

range $62.96 – $187.60

Typical copayment $46.90 (range $15.74 – $46.90)

Most-billed visit code 99205

Established Patient

$77.96 typical visit price

range $20.84 – $153.61

Typical copayment $19.49 (range $5.21 – $38.40)

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.

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 Liam Ghiam's NPI number?

The NPI number for Liam Ghiam is 1689123879. It was assigned to this individual provider in the NPPES registry on September 28, 2016. The provider is also known as Dr. Alireza Ghiam MD, Ms.

Where is Liam Ghiam located?

Liam Ghiam practices at 3951 Katella Ave Ste 102, Los Alamitos, CA 90720. The listed phone number is (562) 799-3198.

What is Liam Ghiam's specialty?

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

Is Liam Ghiam enrolled in Medicare?

Yes. Liam Ghiam 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.

Which organizations bill Medicare for Liam Ghiam's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Liam Ghiam reassigns Medicare benefits to 2 organizations: Uc Regents Department Of Radiation Oncology (Orange, CA) and Usc Care Medical Group, Inc (Los Angeles, CA). Each reassignment is filed with Medicare on form CMS-855R, signed by both the clinician and the organization, and lets the organization bill Medicare and receive payment for Liam Ghiam's services. Reassignment records can lag staffing changes; confirm current arrangements with the organization.

When was this NPI record last updated?

The NPPES record for Liam Ghiam was last updated on July 10, 2025. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 15 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.