ucsf logo

Nicolas Prionas, MD, PhD

Radiation Oncology
Radiation Oncology Mount Zion
415-353-3900
ucsf logo

Nicolas Prionas, MD, PhD

Radiation Oncology
Radiation Oncology Mount Zion
415-353-3900

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
    73 ratings
    About provider reviews

    Showing 1-6 of 25 reviews

    Sort by
    • 5 out of 5 Stars
      February 27, 2026

      Dr Prionas is kind, caring and a great listener.. In addition to being a well-informed and great doctor, He made me feel comfortable from day one and I still feel the same way today.Offered suggestions to help my issues and made sure to let me know if I needed or wanted anything else to contact him!

    • 5 out of 5 Stars
      February 14, 2026

      Dr. Prionas provided an outstanding experience from start to finish. He was incredibly thorough during my appointment, taking the time to carefully explain everything and ensure I fully understood my options. I truly appreciated how patient he was with all of my questions. He never made me feel rushed and addressed each concern thoughtfully and clearly.His depth of knowledge and professionalism were evident throughout the entire visit. I left the appointment feeling confident in his care and grateful for the attention and respect he showed. I highly recommend Dr. Prionas to anyone looking for a knowledgeable, attentive, and compassionate radiation oncologist.

    • 5 out of 5 Stars
      February 14, 2026

      Both Dr Rachael Conger and Dr. Nicolas Prionas provided excellent care! They communicated clearly, listened well, and were kind and empathetic. I appreciate being able to have met with them both.

    • 5 out of 5 Stars
      February 2, 2026

      Excellent care

    • 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.

    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.