Doctor profile · Federal record

Dr. Mark Hwang

Radiation Oncology Physician (CMS: Radiation Oncology) · Student in an Organized Health Care Education/Training Program · Greenwich, CT

  • NPI 1487049037
  • Accepts Medicare
  • 11 yrs in practice
  • Male
  • Group practice
  • No sanctions

Practice & contact

NPPES Updated May 11, 2026
Primary practice
5 Perryridge RD
Greenwich, CT 068304608
(208) 863-3911
Mailing address
622 W 168Th St, Chony North Basement Room 11
New York, NY 100323720

Credentials & registration

NPPES · NUCC
NPI registered
March 2015 — 11 yrs on file
Profile last updated
November 18, 2020
Year of graduation
2015 — 11 yrs since
Specialty taxonomy
2085R0001X — NUCC code
State license (1)
Wisconsin #73946

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1487049037. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
2,376
Distinct HCPCS
10
Medicare allowed
$209,406
HCPCS Description Services Patients Avg allowed
77014 Ct guidance for insertion of radiation therapy fields 848 54 $43
77014 Ct guidance for insertion of radiation therapy fields 435 23 $43
77300 Calculation of radiation therapy dose 158 59 $31
77427 Radiation treatment management, 5 treatment sessions 144 40 $180
77427 Radiation treatment management, 5 treatment sessions 128 40 $180
77334 Design and construction of complex radiation treatment device 86 53 $58
77263 Complex radiation therapy planning 71 68 $159
99213 Established patient office or other outpatient visit, 20-29 minutes 57 53 $61
99213 Established patient office or other outpatient visit, 20-29 minutes 53 52 $62
77301 High precision radiation therapy planning 46 45 $402

In context: peer comparison

Among 1 peers in this city , average services per provider: 99. This provider delivers 24× the peer median.

Open Payments

Industry payments received

CMS Open Payments
All-time total
$20
Transactions
1
Manufacturers
1
Payer (manufacturer) Industry Txns Amount
Siemens Medical Solutions USA, Inc. 1 $20.40

By nature of payment

Food and Beverage
$20

Medicare Part D · 2023

Top prescriptions

CMS Part D Prescriber
Total claims
716
Patients
241
Total drug cost
$14,997
Drug Type Claims Patients Total cost
Tamsulosin Hcl Generic 477 156 $9,063
Oxybutynin Chloride Er (Oxybutynin Chloride) Brand 142 46 $4,521
Megestrol Acetate Generic 44 17 $701
Methylprednisolone Generic 29 22 $278
Alfuzosin Hcl Er (Alfuzosin Hcl) Brand 12 0 $271
Ondansetron Odt (Ondansetron) Brand 12 0 $163

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. Mark Hwang's medical specialty?
Dr. Mark Hwang practices Radiation Oncology Physician in Greenwich, CT.
Where does Dr. Mark Hwang practice?
Dr. Mark Hwang practices at 5 Perryridge RD, Greenwich, CT 068304608. Office phone: 2088633911.
What is Dr. Mark Hwang's NPI?
Dr. Mark Hwang's National Provider Identifier (NPI) is 1487049037, issued by NPPES.
Does Dr. Mark Hwang accept Medicare assignment?
Yes. Dr. Mark Hwang accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Mark Hwang commonly perform?
Top Medicare-reported procedures in 2023: Ct guidance for insertion of radiation therapy fields (HCPCS 77014); Ct guidance for insertion of radiation therapy fields (HCPCS 77014); Calculation of radiation therapy dose (HCPCS 77300). Source: CMS Medicare Physician & Other Practitioners file.