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John Sylvester, MD

Radiation Oncologist

21st Century Oncology - Lakewood Ranch

(941) 907-9053

 Dr John Sylvester is a Radiation Oncologist with 21st Century Oncology in Bradenton/Sarasota, FL. Previously he was co-founder and Director of The Seattle Prostate Institute and Director of the Puget Sound Tumor Institute. He is lead investigator in multiple prostate cancer trials. He has published over 70 articles in medical journals and multiple medical textbook chapters, on prostate cancer. He co-wrote The Prostate Cancer Treatment Book. He is a member of the American Brachytherapy Society (ABS), The American Society of Therapeutic Radiation Oncology (ASTRO), The AMA, The Florida State Medical Society, and the American College of Radiology.


Dr. John Sylvester completed both his Medical Degree and specialty training in Radiation Oncology at UCLA. He is board certified in Radiation Oncology by the American Board of Radiology. He was awarded the American Cancer Society Fellowship during his year as chief resident at UCLA. He began performing prostate brachytherapy with Dr. Blasko in 1987, and joined the Seattle team full time in 1988. Dr. Sylvester was Director of the Puget Sound Tumor Institute from 1991 through 2000. Dr. Sylvester co-founded the Seattle Prostate Institute in 1997 and served as the Director of Education and Training for 9 years. He ran the internationally renowned monthly program which trained more physicians in prostate cancer treatment, than any other program in the world. He also ran the highly regarded Annual Seattle Advanced Prostate Brachytherapy Conference. Dr. Sylvester was the Director of the Seattle Prostate Institute from 2006-2008. He was in charge of the ABS Fellowship rotation at the Seattle Prostate Institute, a highly competitive and desired Fellowship program for residents in radiation oncology throughout North America. These programs trained lead genitourinary radiation oncologists at UCSF, Harvard, MDAH, UCLA, Univ. Chicago, Emory, Rush, Cleveland Clinic, Wake Forrest, Duke, Princess Margaret, British Columbia Cancer Agency, virtually all of the prostate brachytherapy programs in Australia, New Zealand, England, and South America. Until his move to Florida in 2011, he was the Chief Medical Officer of Proqura, an organization developed by the Seattle team, focused on improving the quality of permanent prostate brachytherapy throughout the world.

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