Colonoscopy clinicians in Tacoma, Washington

CMS lists 35 clinicians with a primary specialty of Gastroenterology, Internal Medicine, Family Practice, or General Practice who have billed Medicare for at least one colonoscopy and practice in Tacoma, Washington (details below).

Colonoscopy volume

Clinician	Colonoscopies billed	Percentile rank
Ajay Pabby, MD	195	88%
Miguel Ordonez Castellanos, MD	185	86%
Andrew Woolf, DO	181	86%
Kalyan Kanneganti, MD	169	84%
Steven Larson, MD	168	84%
Nicolas Villa Guillen, MD	162	82%
Robert Lawson	156	81%
Kyung Noh, MD	151	80%
John Sun, MD	127	73%
William Holderman, MD	125	73%
Michael Lee, MD	123	72%
Amy Tsuchida, MD	115	69%
Charles Donner, MD	104	66%
Mark Potter, DO	86	58%
Leonard Philo, MD	84	57%
Patricia Ann Quaine, MD	84	57%
Brian Mulhall, MD	82	56%
Christopher Duncan, MD	81	55%
Jennifer Higa, MD	76	53%
Darren Schwartz, MD	74	52%
Ioannis Papadopoulos, MD	71	50%
Jeffrey Tokar, MD	64	47%
Daniel Bushyhead, MD	54	41%
Surosree Ganguli, MD	53	41%
Kawthar Mohamed, MD	41	33%
Sangik Oh, MD	41	33%
Pierre Nader, MD	34	29%
Nicholas Procaccini, MD	31	27%
Charles Scheurich, MD	28	25%
Lillian Wang, MD	20	19%
Sanjay Agrawal, MD	1-10	13% or below
Ralph Katsman, MD	1-10	13% or below
Pallavi Patel, MD	1-10	13% or below
Kyle Severinsen, MD	1-10	13% or below
Gary Taubman, MD	1-10	13% or below

Sorted by the number of colonoscopies billed to Medicare, highest first, not by quality or skill. CMS suppresses counts between 1 and 10 to protect patient privacy and publishes the range instead.

Understanding CMS Data

CMS's "Colonoscopy" category combines specific billing codes for colonoscopy to calculate the number of times each clinician billed Medicare for a "Colonoscopy." These include screening colonoscopy, diagnostic colonoscopy, and colonoscopy with biopsy or polyp removal. CMS's list also includes flexible sigmoidoscopy and laparoscopic appendectomy, so a clinician's count may include those procedures. CMS counts one procedure per patient per day, so a colonoscopy that included both a biopsy and a polyp removal counts once. CMS reports only procedures that clinicians billed to Original Medicare and Medicare Advantage. Therefore, CMS's procedure volume data does not include procedures that clinicians may have performed on patients who have other health care coverage (e.g., commercial insurance, self-pay, or the VA). Billing variation and coding errors can also affect CMS's data. Therefore, the number of procedures that CMS reports for a clinician may be higher or lower than the actual number of colonoscopies a clinician performed during the reporting period. Lastly, only clinicians with a primary specialty of Gastroenterology, Internal Medicine, Family Practice, or General Practice (as reported to Medicare) are presented.

Source: Centers for Medicare & Medicaid Services (August 18, 2026 release).