Dr. Ari Katerelos is a dedicated board-certified Radiation Oncologist who has recently joined GRMC from California. Formerly, he served as a physician at the California Proton Treatment Center. He earned his Bachelor of Science degree from the California State University at Los Angeles, and subsequently attained his Doctor of Medicine from the David Geffen School of Medicine at UCLA.

Dr. Katerelos completed his internship in Internal Medicine at UCLA Olive View and pursued his residency in Radiation Oncology at Loma Linda University Medical Center, where he had the honor of serving as chief resident.

He has previously held academic positions as an Assistant Clinical Professor at both City of Hope and Loma Linda Medical Center, where he pioneered innovative treatment protocols aimed at optimizing patient outcomes.

At GRMC, Dr. Katerelos has swiftly established himself as a provider of personalized and holistic care, utilizing cutting-edge imaging technologies and modern radiation therapies. His unwavering commitment to patient-centered treatment and his passion for advancing oncology practices make him a vital member of GRMC’s healthcare team and a trusted resource for the community.

Outside of his professional commitments, Dr. Katerelos enjoys Brazilian Jiu Jitsu, crossfit, swimming, and playing games with friends.

• Bachelor of Science
   California State University, Los Angeles, CA

• Doctor of Medicine
   David Geffen School of Medicine at UCLA
   Los Angeles, CA

• Residency
   Internal Medicine, Olive View at UCLA
   Sylmar, CA

• Fellowship
   Radiation Oncology, Loma Linda University Medical Center
   Loma Linda, CA

•  Radiation Oncologist
    California Proton Treatment Center

•  Radiation Oncologist & Assistant Clinical Professor,
    Department of Radiation Oncology
    City of Hope

•  Attending Physician, Department of Radiation Medicine
    Loma Linda Medical Center

•  Attending Physician, Assistant Clinical Professor
    Department of Radiation Medicine
    Loma Linda Medical Center

•  Department Lead of Head and Neck Service

•  LVN, RN, & Charge Nurse
    Oncology Floor, Northridge Hospital and Medical Center

•  Radiology X-Ray Supervisor and Operator