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Radiation Oncology

Derrick Koo, MD

Sees patients in Stockton, CA · California

Summary

Derrick Koo, MD (Radiation Oncology) is enrolled with Medicare at 1 practice location in Stockton, CA. NPI 1902984495. Medicare data says the clinician accepts Medicare assignment. Source: CMS National Downloadable File, updated 2026-10-02.

From official Medicare data

This page shows what Medicare's official clinician data says about Derrick Koo, 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

Radiation OncologyPrimary specialty
YesAccepts Medicare assignment
27Years since medical school (graduated 1999)
MaleGender (as listed)
Permanente Medical Group IncGroup practice

Quick answers

Where does Derrick Koo see patients?
Medicare's clinician data lists 1 practice location in Stockton, CA. Call before your visit to confirm the address.
What is Derrick Koo's specialty?
Medicare lists Radiation Oncology as the primary specialty.
Does Derrick Koo accept Medicare assignment?
Yes. Medicare's clinician data says Derrick Koo 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.
What is the phone number for Derrick Koo?
(209) 476-2000, as listed in official Medicare / NPI Registry data.
What is Derrick Koo's NPI number?
1902984495. The NPI (National Provider Identifier) is the clinician's permanent federal ID; you can look it up in the official NPI Registry.

Practice locations

Addresses where Derrick Koo is enrolled with Medicare (CMS data updated 2026-10-02).

Group practices

Medicare enrollment lists Derrick Koo as a member of this group (CMS data updated 2026-10-02).

  • Permanente Medical Group Inc10,996 clinicians in the group

Specialties

Find other Radiation Oncology doctors in California →

Other radiation oncologists in Stockton

Clinicians with the same Medicare primary specialty in Stockton, CA — not a recommendation.

All radiation oncologists in Stockton →

Clinician information

CredentialMD
Graduation year1999
Gender (as listed)Male
Medicare assignmentAccepts (Medicare-approved amount as full payment)
NPI (National Provider Identifier)1902984495
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. National Downloadable File (Doctors and Clinicians) — CMS, data updated 2026-10-02, retrieved 2026-10-29
  2. NPI Registry — U.S. Department of Health and Human Services (NPPES), the clinician’s official record
  3. Medicare Care Compare — official Medicare tool to look up clinicians