Mark Anthony Sitarik, MD
Hematology & Oncology Physician · Boulder, CO
Mark Anthony Sitarik, MD is a hematology & oncology physician with a practice address in Boulder, Colorado, and NPI 1346224664, issued on Nov 30, 2005. Check the license (Colorado 26965, as entered in NPPES) on the Colorado Medical Board; the Medicare figures below come from public CMS files.
- Name
- Mark Anthony Sitarik
- Credential
- MD
- Primary taxonomy
- Hematology & Oncology Physician 207RH0003X
- License number
- 26965 CO
Self-reported in NPPES; status is on the state search - Practice location
- 4715 Arapahoe Ave, Boulder, CO 80303
- Phone
- (303) 385-2000
- Enumerated
- Nov 30, 2005
- Record last updated
- Jul 15, 2011 (not updated in 15 years: call before relying on the address or phone)
- Fax
- (303) 444-1839
- Medicaid ID
- 01269653 CO
- Medicare enrollment
- Enrolled (PECOS I20091201000492); accepts Medicare assignment
- Medical or professional school
- Hahneman Medical College Of The Pacific, 1982
- Entity
- Type 1 · individual
8 nearest hematology & oncology physician records → All 212 in Colorado → Look up another NPI →
Also registered at 4715 Arapahoe Ave
A shared address usually means a shared clinic or building; it does not show who employs whom.
- David Andorsky, MDHematology & Oncology Physician1609061837
- Andrew Antell, MDRadiation Oncology Physician1508840158
- Terri Bauer, LCSWClinical Social Worker1841509056
- Gregory Britt, M.D.Hematology & Oncology Physician1982645982
- Leslie Busby, MDHematology & Oncology Physician1952385502
- John Fleagle, MDHematology & Oncology Physician1346224433
Verify Mark Anthony Sitarik in five checks
- 1IdentityNPI record in CMS NPPESNPI lookupConfirmed in NPPES
- 2LicenseActive license and public ordersColorado Medical Board
Search for license 26965Check the board - 3Other statesLicenses and actions elsewhereDocInfo (FSMB)Not checked
- 4ExclusionsMedicare and Medicaid bansHHS-OIG exclusion listNot checked
- 5CertificationBoard certificationABMS AOA NCCPA AANPNot checked
53% more Medicare Part D claims than the average hematology & oncology physician in 2024
1,345 Medicare Part D claims for 184 beneficiaries, against an average of 877 among the 10,784 providers of this specialty who prescribed in Part D. 100 claims were for opioids.
Most prescribed
- Anastrozole100 claims
- Eliquis64 claims
- Lorazepam60 claims
- Hydroxyurea53 claims
- Acyclovir52 claims
- Prednisone46 claims
Source: CMS Medicare Part D Prescribers by Provider and Drug, 2024 (data.cms.gov). Part D covers prescriptions for Medicare patients only; drugs with fewer than 11 claims are not published.
The MIPS final score for 2023 (Medicare payment program): 84.8 of 100
The Merit-based Incentive Payment System score is reported for this clinician. Four categories are weighted into the final score; the average among 454,083 clinicians with a measured score was 83.5.
Source: CMS Quality Payment Program, MIPS performance year 2023; category weights for 2023 (qpp.cms.gov).
Bills Medicare through one group practice
- Rocky Mountain Cancer Centers LLPBoulder, CO
Source: CMS Doctors and Clinicians National Downloadable File (the group practices a clinician bills Medicare through) (data.cms.gov).
Mark Anthony Sitarik among 212 hematology & oncology physician records in Colorado
Mark Anthony Sitarik, MD is one of 212 hematology & oncology physician records with a practice address in Colorado. 77% of them appear in a Medicare file (Part D prescribing, MIPS, Open Payments or Medicare group billing); this one does. Its NPI, issued in 2005, is newer than 0% of them.
- NPI issued2005 · 0% of these records are older, 70% newer
- In a Medicare fileYes · 77% of these records are
- In the CMS Doctors and Clinicians fileYes · 71% of these records are
- Graduated1982 · median 2004 among the 150 with a school on file
- Record last updated2011 · 59% of these records were not updated in five years or more
Source: CMS NPPES, file of Aug 9, 2026, every record with primary taxonomy 207RH0003X and a Colorado practice address; Medicare files: CMS Part D Prescribers 2024, MIPS 2023, Open Payments 2024, Doctors and Clinicians (data.cms.gov).
Hematology & Oncology Physician providers in Colorado
There are 212 hematology & oncology physician records in Colorado.
All 212 in Colorado → Every provider in Boulder → Hematology & Oncology Physician nationwide →
The 8 hematology & oncology physician records with the nearest ZIP codes
- David Andorsky, MDBoulder, CO 803031609061837
- Gregory Britt, M.D.Boulder, CO 803031982645982
- Leslie Busby, MDBoulder, CO 803031952385502
- John Fleagle, MDBoulder, CO 803031346224433
- Jenny Fox, MDBoulder, CO 803031295719904
- Lori Jensen, MDBoulder, CO 803031437133527
- Patrick Moran, MDBoulder, CO 803031376520478
- Austin Poole, MDBoulder, CO 803031053686253
Common questions
What is Mark Anthony Sitarik, MD's NPI number?
Mark Anthony Sitarik, MD's National Provider Identifier (NPI) is 1346224664, issued on Nov 30, 2005. An NPI identifies a provider in billing; it is not a license.
Where is Mark Anthony Sitarik, MD located?
The NPPES record lists a practice address at 4715 Arapahoe Ave, Boulder, CO, 80303. Phone: (303) 385-2000. Providers update this record themselves, so call before visiting.
How can I verify Mark Anthony Sitarik, MD's license?
NPPES lists Colorado license number 26965, as entered by the provider. Search the Colorado Medical Board at https://dpo.colorado.gov/Medical. The NPPES record confirms identity only; the state search shows license status, expiration and public orders.
How much does Mark Anthony Sitarik, MD prescribe under Medicare Part D?
In 2024, Mark Anthony Sitarik, MD had 1,345 Medicare Part D claims for 184 beneficiaries; the average among hematology & oncology physician prescribers was 877. Part D covers Medicare prescriptions only.
What is Mark Anthony Sitarik, MD's MIPS final score?
The 2023 MIPS final score is 84.8 of 100. The average among 454,083 clinicians with a measured score was 83.5.
Source: CMS National Plan and Provider Enumeration System (NPPES), file of Aug 9, 2026 (NPPES files on CMS.gov); NUCC Health Care Provider Taxonomy. Medicare files from data.cms.gov. An NPI identifies who bills; it is not a license.
Figures on PlainDoctor are read from the federal files each page names (CMS NPPES, Medicare Part D, MIPS, Open Payments; the HHS-OIG exclusion list only as counts) and from Census population estimates, with the file date shown beside them. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of Aug 9, 2026.