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DR. HELEN HENG-SHAN MOON M.D.
NPI 1255480075
Internal Medicine - Hematology & Oncology in Pasadena, CA

Active since January 10, 2007PECOS EnrolledAccepts Medicare Assignment
393 E WALNUT ST FL 3, PASADENA, CA 91188(951) 353-4931 Get Directions Write a Review

NPPES record last updated: November 1, 2021. Verified against the NPPES registry weekly; last sync: October 25, 2026.

About Dr. Helen Heng-shan Moon M.d. NPPES

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

DR. HELEN HENG-SHAN MOON M.D. (NPI 1255480075) is an individual hematology & oncology provider in Pasadena, California, licensed in California (A91007) and active in the NPI registry since January 2007. She is enrolled in Medicare PECOS and is a graduate of Other (2003).

NPPES Registry Identity

NPI1255480075
Entity TypeIndividualFemale
Primary Taxonomy207RH0003X
Provider Legal NameDR. HELEN HENG-SHAN MOONCredential: M.D.
Location Address393 E WALNUT ST FL 3Pasadena, CA 91188-0001
Mailing Address393 E Walnut St Fl 3Pasadena, CA 91188-0001
Phone(951) 353-4931
Sole ProprietorYes
Medical School CMSOtherGraduated 2003
Enumeration DateJanuary 10, 2007
Last NPPES UpdateNovember 1, 2021
NPPES CertifiedNovember 1, 2021
✔ NPI 1255480075 is a valid, active identifier and passes the ISO check-digit test.

Specialties & Licenses 2

★ Primary SpecialtyInternal Medicine · Hematology & OncologyAllopathic & Osteopathic Physicians
Taxonomy Code207RH0003X
License✔ Licensed in CA · A91007
Definition
An internist doctor of osteopathy that specializes in the treatment of the combination of hematology and oncology disorders. A doctor of osteopathy that is board eligible/certified by the American Osteopathic Board of Internal Medicine WAS able to obtain a Certificate of Special Qualifications in the field of Hematology and Oncology. The Certificate is NO longer offered.
Also ListedInternal MedicineTaxonomy 207R00000X · License A91007 (CA)
393 E WALNUT ST FL 3, Pasadena, CA 91188
Open in Google Maps ↗

Other Names 1

Former Name (1)Dr. Helen Heng-shan Gu M.d.

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. Helen Heng-shan Moon 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 ID6002990538
PECOS Enrollment IDI20080222000239
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 Reassignment

Medicare enrollment records show Helen Moon reassigns Medicare billing to 1 organization. The organization bills Medicare for the services this provider delivers there.

Southern California Permanente Medical Group
4.7 mi
Health Maintenance Organization
2626 COLORADO BLVD
Los Angeles, CA 90041
  • Reassigned Medicare billing, California enrollment
  • Also billed through NPI 1396287082 (California)
  • 13,921 clinicians in this Medicare group
NPI 1013409044 (877) 608-0044

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

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.

Infusion, normal saline solution , 1000 cc J7030
An infusion of normal saline solution, 1000 cc, is a common medical procedure. It involves introducing a saltwater solution into your bloodstream via an intravenous (IV) line. This helps to hydrate your body, correct electrolyte imbalances, and deliver medications if needed.
42 services13 patients

Physician Visit Costs CMS claims · ZIP area

Typical Medicare office-visit costs in the 91188 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
$109.96 typical visit price
range $20.84 – $153.61
Typical copayment $27.49 (range $5.21 – $38.40)
Most-billed visit code 99214
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.

ASHLEY SANDERS ZAPATA
Marriage & Family Therapist
393 E WALNUT ST FL 3
PASADENA, CA 91188
Los Angeles County (803) 316-3757
IRIS CRUZ
Counselor (Mental Health)
393 E WALNUT ST FL 3
PASADENA, CA 91188
Los Angeles County (626) 405-6130
LILLI ANN GOCO REYES MD
Family Medicine
393 E WALNUT ST FL 3
PASADENA, CA 91188
Los Angeles County (626) 405-5951
JANELLE JANA WARMINGTON M.D.
Obstetrics & Gynecology
393 E WALNUT ST FL 3
PASADENA, CA 91188
Los Angeles County (877) 608-0044
JENNIFER LYN STURM LCSW
Counselor (Mental Health)
393 E WALNUT ST FL 3
PASADENA, CA 91188
Los Angeles County (833) 511-0106
JANET J KINKEAD D.O.
Family Medicine (Addiction Medicine)
393 E WALNUT ST FL 3
PASADENA, CA 91188
Los Angeles County (619) 629-8787
DR. MARIE M SAINT LOUIS DPM
Podiatrist (Foot & Ankle Surgery)
393 E WALNUT ST FL 3
PASADENA, CA 91188
Los Angeles County (917) 727-4302
DR. MAY T LYNN M.D.
Family Medicine
393 E WALNUT ST FL 3
PASADENA, CA 91188
Los Angeles County (626) 405-5113

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 Helen Moon's NPI number?

The NPI number for Helen Moon is 1255480075. It was assigned to this individual provider in the NPPES registry on January 10, 2007. The provider is also known as Dr. Helen Heng-Shan Gu M.D..

Where is Helen Moon located?

Helen Moon practices at 393 E Walnut St Fl 3, Pasadena, CA 91188. The listed phone number is (951) 353-4931.

What is Helen Moon's specialty?

The primary specialty registered for this NPI is Internal Medicine, specializing in Hematology & Oncology, with taxonomy code 207RH0003X.

Is Helen Moon enrolled in Medicare?

Yes. Helen Moon 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 organization bills Medicare for Helen Moon's services?

According to the CMS Revalidation Reassignment List (October 2026 release), Helen Moon reassigns Medicare benefits to Southern California Permanente Medical Group (Los Angeles, CA). The 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 Helen Moon'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 Helen Moon was last updated on November 1, 2021. NPI Profile syncs weekly with the NPPES registry data releases published by CMS. This NPI record was last updated 4 years 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.