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Medical Oncology

Mark L. Sundermeyer, MD

Works at hospitals in Saint Louis, MO · Creve Coeur, MO · Belleville, IL … · Missouri, Illinois

Summary

Mark L. Sundermeyer, MD (Medical Oncology) is listed by Medicare at 5 hospitals in Saint Louis, MO, Creve Coeur, MO and Belleville, IL and other places. NPI 1386690337. Medicare data says the clinician accepts Medicare assignment. Source: CMS Facility Affiliation Data, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Mark L. Sundermeyer, joined by NPI number (data updated 2026-10-02). It is not a recommendation or a rating. Call the office or hospital to confirm before you go.

In a medical emergency, call 911.

At a glance

Medical OncologyPrimary specialty
YesAccepts Medicare assignment
YesOffers telehealth
26Years since medical school (graduated 2000)
University Of Missouri, Columbia School Of MedicineMedical school
MaleGender (as listed)
Washington UniversityGroup practice

Quick answers

Which hospitals does Mark L. Sundermeyer work at?
Medicare's official clinician data lists Mark L. Sundermeyer at 5 hospitals: Barnes Jewish Hospital, Barnes-Jewish West County Hospital, Christian Hospital Northeast, Memorial Hospital and Parkland Health Center. This is where the clinician works or has privileges; call the hospital to confirm.
Where does Mark L. Sundermeyer see patients?
Medicare's clinician data lists 1 practice location in Saint Louis, MO. Call before your visit to confirm the address.
What is Mark L. Sundermeyer's specialty?
Medicare lists Medical Oncology as the primary specialty, and also Internal Medicine.
Does Mark L. Sundermeyer accept Medicare assignment?
Yes. Medicare's clinician data says Mark L. Sundermeyer accepts Medicare assignment (the Medicare-approved amount as full payment for covered services), as of 2026-10-02. Ask the office to confirm before your visit.
Does Mark L. Sundermeyer offer telehealth?
Medicare's clinician data says Mark L. Sundermeyer offers telehealth services. Ask the office which visits can be done by video or phone.
What is the phone number for Mark L. Sundermeyer?
(800) 647-2098, as listed in official Medicare / NPI Registry data.
What is Mark L. Sundermeyer's NPI number?
1386690337. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Hospitals where Mark L. Sundermeyer works

Medicare's Facility Affiliation Data lists Mark L. Sundermeyer at these hospitals (updated 2026-10-02). Each hospital page shows its address, phone, emergency services, Medicare rating and all its clinicians.

Practice locations

Addresses where Mark L. Sundermeyer is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Mark L. Sundermeyer as a member of this group (CMS data updated 2026-10-02).

  • Washington University3,029 clinicians in the group

Specialties

Find other Medical Oncology doctors in Missouri →

Other oncologists in Saint Louis

Clinicians with the same Medicare primary specialty in Saint Louis, MO — not a recommendation.

All oncologists in Saint Louis →

Clinician information

CredentialMD
Medical schoolUniversity Of Missouri, Columbia School Of Medicine
Graduation year2000
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
TelehealthOffers telehealth services
NPI (National Provider Identifier)1386690337
CorrectionsReport an error or suggest an update →

Most corrections must be made at the source: clinicians update their NPI Registry record (NPPES) and their Medicare enrollment (PECOS); this page follows the next data release.

Sources

  1. Facility Affiliation Data — Centers for Medicare & Medicaid Services (CMS), data updated 2026-10-02, retrieved 2026-10-29
  2. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  3. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  4. Medicare Care Compare — official Medicare tool to look up clinicians