Nan Chen
NPI 1558749887 · Medical Oncology Physician · Chicago, IL
Enrolled with Medicare as Practitioner - Hematology/Oncology · source: CMS PECOS Public Provider Enrollment (2026.04.01)
Nan Chen is a Medical Oncology Physician provider in Chicago, IL (NPI 1558749887).
Provider details
- NPI number
- 1558749887
- Entity type
- Individual
- Primary specialty
- Medical Oncology PhysicianAllopathic & Osteopathic Physicians
- Sex
- Female
- Sole proprietor
- Yes
- License
- 036156991 (IL)
Specialties & taxonomies
Allopathic & Osteopathic Physicians
Allopathic & Osteopathic Physicians
Profile Score
A profile completeness & documented-activity index — NOT a quality, outcomes, or patient-satisfaction rating.
- Registry tenure25% of score
11 yrs in NPPES registry
- Profile completeness25% of score
100% of core fields populated
- Practice footprint15% of score
2 documented practice locations
- Medicare service volume (vs. specialty peers)25% of score
658 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) |
|---|---|---|
| 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 | 193 | $18 |
| Established Patient Office Or Other Outpatient Visit With Moderate Level of Decision Making, If Using Time, 30 Minutes Or More99214 | 181 | $106 |
| Subsequent Hospital Care With Moderate Levelof Medical Decision Making, If Using Time, at Least 50 Minutes99233 | 127 | $130 |
| Established Patient Office Or Other Outpatient Visit With High Level of Medical Decision Making, If Using Time, 40 Minutes Or More99215 | 77 | $159 |
| New Patient Office Or Other Outpatient Visit With a High Level of Medical Decision Making, If Using Time, 60 Minutes Or More99205 | 30 | $201 |
What this provider prescribes (Medicare Part D)
Top drugs by Medicare Part D claim volume, 2024 · 12 distinct drugs on file.
| Drug | Part D claims (2024) | Beneficiaries |
|---|---|---|
| Letrozole | 182 | 64 |
| Anastrozole | 95 | 34 |
| Exemestane | 76 | 20 |
| Tamoxifen Citrate | 61 | 22 |
| Ribociclib Succinatebrand: Kisqali | 30 | — |
| Palbociclibbrand: Ibrance | 25 | — |
| Ondansetron Hcl | 24 | — |
| Prochlorperazine Maleate | 21 |
Transparency — industry payments
Based on CMS Open Payments, 2024; not all care is captured.
$8,388 across 8 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
Additional practice locations (1)
- 10855 Virginia StCrown Point, IN 46307-0210Phone: (888) 824-0200
Registry dates
- Enumerated
- 2015-05-06
- Last updated
- 2026-06-04
- Certified
- 2026-06-04
Frequently asked questions
- What is Nan Chen's NPI number?
- Nan Chen's National Provider Identifier (NPI) is 1558749887, a unique 10-digit ID issued by CMS for use in standard healthcare transactions.
- What is Nan Chen's specialty?
- Nan Chen is listed in the NPPES registry with a primary specialty of Medical Oncology Physician (Allopathic & Osteopathic Physicians).
- Where is Nan Chen located?
- Nan Chen's practice location on file with NPPES is 5841 S Maryland Ave, Chicago, IL 60637-1443.
- What is Nan Chen's phone number?
- The practice phone number listed in the NPPES registry for Nan Chen is (888) 824-0200.
- Does Nan Chen accept Medicare?
- Nan Chen is approved to bill Medicare according to CMS PECOS enrollment data (2026.04.01). Confirm current participation with the provider before scheduling.
- Is Nan Chen's NPI active?
- Yes — Nan Chen's NPI (1558749887) is active in the NPPES registry as of the last update on 2026-06-04.
Source: CMS NPPES Data Dissemination (June 2026). NPI Central is not affiliated with CMS. Data is provided as-is from the public registry.