Provider records sourced from NPPES (CMS National Plan & Provider Enumeration System). Data current as of August 10, 2026.

Dr. Mark Joseph Fesler, MD

Individual provider Internal Medicine Physician · NPI 1235204066

Dr. Mark Joseph Fesler, MD is a Hematology/Oncology in Saint Louis, Missouri. Graduated from Saint Louis University School of Medicine in 2003, 23 years ago. Practices with Van Amburg and Busiek Mds LLC, a 9-clinician group, accepts Medicare assignment and offers telehealth. Licensed in Colorado and Missouri.

Years since qualifying
23
Trained at
Saint Louis University School of Medicine
Licensed in
CO, MO
In the registry since
2006
Specialties on file
2
What do these letters mean?
MD — Doctor of Medicine
A physician who completed allopathic medical school.

See every abbreviation used in this directory →

Practice location Address checks out

3655 Vista Ave
Saint Louis, MO 63110-2539
Phone: (314) 977-4340
Fax: (314) 773-1167
Show map & directions

Pin is approximate — placed at the ZIP-code centre, not the exact door.

Specialties & licences

Hematology & Oncology Physician (primary) Taxonomy 207RH0003X · Licence 2008029015 (MO)
Internal Medicine Physician Taxonomy 207R00000X · Licence 43133 (CO)

Record details

NPI number1235204066
Entity typeIndividual (Type 1)
GenderMale
Credentials MD
Sole proprietorNo
NPI enumeratedNovember 21, 2006
Last updated in NPPESMarch 29, 2021
Certification dateMarch 29, 2021

Medicare enrollment

From the CMS Doctors & Clinicians file — this clinician is enrolled in Medicare.

Medicare specialtyHEMATOLOGY/ONCOLOGY
Also practisesHEMATOPOIETIC CELL TRANSPLANTATION AND CELLULAR THERAPY
Medical schoolSAINT LOUIS UNIVERSITY SCHOOL OF MEDICINE
Graduated 2003 (23 years in practice)
Group practice Van Amburg And Busiek Mds Llc — 9 clinicians
Accepts Medicare assignment Yes — accepts the Medicare-approved amount
TelehealthOffers telehealth services

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