Doctor profile · Federal record

Dr. Ann Lee, M.D.

Gastroenterology Physician (CMS: Gastroenterology) · Gastroenterology Physician · Downey, CA

  • NPI 1396979126
  • Accepts Medicare
  • MIPS 81.5 / 100 · 2023
  • 18 yrs in practice
  • Licensed in 2 states
  • Female
  • Group practice
  • No sanctions

Practice & contact

Operates at 3 locations .

NPPES Updated May 11, 2026
Primary practice
10441 Lakewood Blvd Ste B
Downey, CA 902412871
(562) 869-4497
Additional location
8810 C Avenue, Apt 134
Hesperia, CA 92345
(714) 788-8218
Additional location
9831 S Western Ave
Chicago, IL 606431740
(773) 445-3500
Mailing address
Po Box 35380
Las Vegas, NV 891335380

Credentials & registration

NPPES · NUCC
NPI registered
May 2009 — 17 yrs on file
Profile last updated
December 29, 2025
Year of graduation
2008 — 18 yrs since
Specialty taxonomy
207RG0100X — NUCC code
State licenses (2)
Illinois #036-167184 · California #136160

Federal sanctions & exclusions

OIG LEIE Updated May 11, 2026

No sanctions, exclusions or revocations on file

Checked against OIG LEIE on NPI 1396979126. Last verified May 11, 2026.

Medicare procedures · 2023

Top services delivered

CMS Provider Utilization
Total services
342
Distinct HCPCS
6
Medicare allowed
$35,991
HCPCS Description Services Patients Avg allowed
99232 Subsequent hospital care with moderate levelof medical decision making, if using time, at least 35 minutes 141 90 $77
99222 Initial hospital care with straightforward or low-level medical decision making, if using time, at least 55 minutes 73 71 $127
43239 Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope 38 38 $101
45380 Biopsy of large bowel using a flexible endoscope 38 37 $95
99233 Subsequent hospital care with moderate levelof medical decision making, if using time, at least 50 minutes 29 18 $107
45385 Removal of polyps or growths of large bowel using an endoscope with mechanical snare 23 22 $229

In context: peer comparison

Among 2 peers in Downey Gastroenterology Physician, average services per provider: 41. This provider delivers 8.3× the peer median.

Hospital affiliations

CMS Hospital Compare

Frequently asked questions

Auto-generated from federal data
What is Dr. Ann Lee's medical specialty?
Dr. Ann Lee practices Gastroenterology Physician in Downey, CA.
Where does Dr. Ann Lee practice?
Dr. Ann Lee practices at 10441 Lakewood Blvd Ste B, Downey, CA 902412871. Office phone: 5628694497.
What is Dr. Ann Lee's NPI?
Dr. Ann Lee's National Provider Identifier (NPI) is 1396979126, issued by NPPES.
Does Dr. Ann Lee accept Medicare assignment?
Yes. Dr. Ann Lee accepts Medicare assignment, meaning Medicare-allowed amounts are accepted as full payment for covered services.
What procedures does Dr. Ann Lee commonly perform?
Top Medicare-reported procedures in 2023: Subsequent hospital care with moderate levelof medical decision making (HCPCS 99232); Initial hospital care with straightforward or low-level medical decision making (HCPCS 99222); Biopsy of esophagus, stomach, and/or upper small bowel using a flexible endoscope (HCPCS 43239). Source: CMS Medicare Physician & Other Practitioners file.