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Nicolas Prionas, MD, PhD

Radiation Oncology
Radiation Oncology Mission Bay
415-353-7175
ucsf logo

Nicolas Prionas, MD, PhD

Radiation Oncology
Radiation Oncology Mission Bay
415-353-7175

On this page

About me

Dr. Nicolas Prionas is a radiation oncologist who cares for adults with all types of cancer. He has a special interest in treating breast cancer.

In research, Prionas focuses on developing new technologies to improve the early detection, diagnosis and treatment of cancer. He is also interested in exploring applications of technology to increase access to equitable cancer care.

Prionas earned a bachelor's degree in biomedical computation and a master's degree in biomechanical engineering at Stanford University. At the University of California, Davis, he earned both a doctorate in biomedical engineering and his medical degree. He completed a residency in radiation oncology at Stanford Medicine.

Prionas is a member of the American Medical Association, American Society for Radiation Oncology, Radiological Society of North America, American Brachytherapy Society and American Association of Physicists in Medicine. He speaks Greek and Spanish.

Education & training

Board certification

  • Radiation Oncology, American Board of Radiology

Residency

  • Radiation Oncology, Stanford University Hospitals & Clinics GME

Internship

  • Transitional, Santa Clara Valley Medical Center GME

Degree

  • MD, University of California Davis School of Medicine

My expertise

  • Specialties
  • Conditions
  • Treatments
    • Radiation Treatment
    • Total Body Irradiation
    • 3D Conformal Radiation Therapy
    • Volumetric Modulated Arc Therapy
    • Stereotactic Cranial Radiation
    • Three-Dimensional Conformal Radiation Therapy
    • Intraoperative Radiation Therapy
    • Intensity-Modulated Radiation Therapy
    • Image-Guided Radiation Therapy

Locations

    Reviews

    Average rating

    5
    5 out of 5 Stars
    72 ratings
    About provider reviews

    Showing 1-6 of 21 reviews

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    • 5 out of 5 Stars
      January 28, 2026

      Dr. Prionas was truly amazing. I did not feel rushed, he reviewed my entire medical history, and he even brought up thoughts that I never considered with regards to the timing of my radiation. That discussion ultimately involved him going back and talking to the plastic surgeon - he got back to me the following day with an answer. His response was definitely after working hours, which was very considerate of him. He truly is a very nice - honest - and gentle physician.

    • 5 out of 5 Stars
      January 12, 2026

      I had one of the best experiences with a doctor during this visit with Dr. Prionas. He was compassionate, did not rush me, made me feel comfortable and heard and was extremely knowledgeable about a complicated situation.

    • 5 out of 5 Stars
      December 18, 2025

      Dr. Nicholas Prionas is a cut above in terms of knowledge, empathy, patient care, and expertise. Resident Dr. Alex Real is very kind and caring as well.

    • 5 out of 5 Stars
      November 3, 2025

      Each visit has been excellent. Best physician I have had doing on going tx. Yes I recommend UCSF to all my friends who are out of state not receiving optimal health care.

    • 5 out of 5 Stars
      September 26, 2025

      Dr Prionas is the most amazing radiology oncologist for breast cancer!!

    • 5 out of 5 Stars
      September 4, 2025

      Dr. Prionas is the perfect doctor. He's clinical and informative, but also incredibly personable and clearly listens to the patient. I learned new things about my entire cancer journey that I'd never heard from either my surgical or medical oncologist. His bedside manner is the best there could be, and he quickly perceives how to work with each patient. As I have heard others say, "I wish he was my doctor for everything". My immediate thought after the video meeting today was, "Where have you been for the last 6 months"? I wished I'd had a doctor patient relationship with him from the beginning.

    Please check with your health insurance plan regarding coverage for this type of care. Not all providers at UCSF Health are covered by every insurance plan.

    For informational purposes only, a link to the federal Centers for Medicare and Medicaid Services (CMS) Open Payments web page is provided here. The federal Physician Payments Sunshine Act requires that detailed information about payment and other payments of value worth over ten dollars ($10) from manufacturers of drugs, medical devices, and biologics to physicians and teaching hospitals be made available to the public.