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Jason A. Efstathiou, MD, DPhil

  • Phone: 617-726-5866
Department of Radiation Oncology


  • Cancer Center
  • Radiation Oncology
  • Genitourinary Oncology
Clinical Interests
Prostate cancer
Bladder cancer
Testicular, penile and genito-urinary cancers
Kidney cancer
Ureteral / Urethral cancer
Penile cancer
Proton Beam Therapy
Brachytherapy (radioactive seeds)
Boston: Massachusetts General Hospital
Medical Education
MD, Harvard Medical School
DPHIL, University of Oxford
Residency, Brigham and Women's Hospital
Board Certifications
Radiation Oncology, American Board of Radiology
Patient Age Group
Accepting New Patients


Dr. Efstathiou holds a M.D. from Harvard Medical School and completed his residency training in the Harvard Radiation Oncology Program. He serves as Assistant Professor of Radiation Oncology at MGH. His clinical practice focuses on treatment of patients with prostate cancer and other urologic cancers, as well as proton beam and brachytherapy. His current clinical research interests include adverse effects of hormone therapy for prostate cancer, effects of obesity/lifestyle modification on cancer control, long-term outcomes and late toxicities with bladder-sparing chemoradiation, and investigations into proton beam and other emerging technologies for prostate cancer. He is actively involved in clinical trial design both at MGH and within the national cooperative group, Radiation Therapy Oncology Group (RTOG), where he serves as RTOG Chair of the Comparative Effectiveness Subcommittee. A primary focus of his at this time is in comparative effectiveness and the development of a randomized trial of intensity-modulated radiation therapy (IMRT) versus proton beam using patient-reported outcomes, as well as developing the infrastructure for a national radiation oncology registry by leveraging health information technologies. He holds a Ph.D. from the University of Oxford in cancer genetics and remains active in translational science. Other educational/outreach efforts in which he is engaged include the development of web-based prostate cancer patient decision aids and an effort to provide ongoing training to foreign radiation oncologists.


Focused radiation therapy for localized muscle invading bladder cancer in the setting of selective bladder preservation: whole transcriptome analysis based treatment stratification.

PI, Massachusetts General Hospital Cancer Center Thematic Priority Translational Research Award ($50,000)

Hormone therapy for prostate cancer does not appear to increase cardiac deaths

Treating prostate cancer patients with drugs that block hormonal activity does not appear to increase the risk of death from cardiovascular disease, according to a study led by MGH researchers

Clark Center for Radiation Oncology
100 Blossom Street
Boston, MA 02114-2606

Phone: 617-726-5866
Fax: 617-726-3603

Clark Center for Radiation Oncology
100 Blossom Street
Boston, MA 02114-2606

Phone: 617-726-5866
Fax: 617-726-3603

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