Gigi Chen, M.D.
NPI 1821073636 · Hematology & Oncology Physician · Pleasant Hill, CA
Enrolled with Medicare as Practitioner - Hematology/Oncology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Gigi Chen, M.D. is a Hematology & Oncology Physician provider in Pleasant Hill, CA (NPI 1821073636).
Provider details
- NPI number
- 1821073636
- Entity type
- Individual
- Primary specialty
- Hematology & Oncology PhysicianAllopathic & Osteopathic Physicians
- Credential
- M.D.
- Sex
- Female
- Sole proprietor
- No
- License
- A84387 (CA)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
20 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
1 documented practice location
- Medicare service volume (vs. specialty peers)25% of score
3,602 Medicare services, 2024 (ranked within specialty)
- Open Payments transparency10% of score
Has Open Payments disclosures (2024)
Medicare volume is ranked against active providers in the same specialty. Signals a provider has no public data for (e.g. Medicare claims) are left out of the score entirely — never counted as zero — so providers without that data are not penalized. See the full formula and weights in our .
What this provider does (Medicare)
Based on Medicare fee-for-service claims, 2024; not all care is captured.
| Service (HCPCS) | Medicare services | Typical Medicare-allowed (2024) |
|---|---|---|
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 1,012 | $135 |
| Established Patient Office Or Other Outpatient Visit With High Level of Medical Decision Making, If Using Time, 40 Minutes Or More99215 | 489 | $183 |
| Visit Complexity Inherent to Evaluation and Management Associated With Medical Care Services That Serve As the Continuing Focal Point for All Needed Health Care Services And/Or With Medical Care Services That Are Part of Ongoing Care Related to a Patient'SG2211 | 307 | $19 |
| Insertion of Needle Into Vein for Collection of Blood Sample36415 | 246 | $9 |
| Complete Blood Cell Count (red Cells, White Blood Cell, Platelets), Automated Test and Automated Differential White Blood Cell Count85025 | 233 | $8 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 22 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Anastrozole | 64 | 22 |
| Apixabanbrand: Eliquis | 53 | 14 |
| Rivaroxabanbrand: Xarelto | 50 | 17 |
| Letrozole | 39 | 15 |
| Warfarin Sodium | 36 | 12 |
| Gabapentin | 36 | — |
| Ondansetron Hcl | 28 | 13 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$4,528 across 58 records (Open Payments 2024)
Open Payments discloses payments and transfers of value (meals, travel, consulting, research, royalties) from drug and device makers to providers. This is a transparency signal, not a verdict — such payments are legal and common, and their presence is neither an endorsement nor a criticism. Source: CMS Open Payments, program year 2024.
Practice location
Mailing address
Registry dates
- Enumerated
- 2005-12-14
- Last updated
- 2021-08-02
- Certified
- 2021-08-02
Frequently asked questions
- What is Gigi Chen's NPI number?
- Gigi Chen's National Provider Identifier (NPI) is 1821073636, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Gigi Chen's specialty?
- Gigi Chen is listed in the NPPES registry with a primary specialty of Hematology & Oncology Physician (Allopathic & Osteopathic Physicians).
- Where is Gigi Chen located?
- Gigi Chen's practice location on file with NPPES is 400 Taylor Blvd, Pleasant Hill, CA 94523-2147.
- What is Gigi Chen's phone number?
- The practice phone number listed in the NPPES registry for Gigi Chen is (925) 677-5041.
- Does Gigi Chen accept Medicare?
- Gigi Chen is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Gigi Chen's NPI active?
- Yes — Gigi Chen's NPI (1821073636) is active in the NPPES registry as of the last update on 2021-08-02.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.