Dr. William Silveira is a board-certified radiation oncologist in the department of radiation oncology at Community Cancer Institute, Clovis Community Medical Center. He received his medical degree from Harvard Medical School and Ph.D. in chemical physics from Cornell University.

Dr. Silveira is a volunteer assistant clinical professor at University of California, San Francisco, and serves on the College of Mathematics and Science Advisory Board at California State University, Fresno. He is a passionate clinician and leader, recently serving as the medical director for the Department of Radiation Oncology at Community Cancer Institute for the past four years through May 2021. He has been published in numerous journals and has received a number of awards and fellowships, most recently receiving the Fresno State’s 2022 Top Dog Outstanding Alumnus Award College of Science and Mathematics.  

Having grown up in the farming community of Mendota, California, he is dedicated to provide the best oncologic care for people in the Central Valley.

Education and Certifications


Santa Clara Valley Medical Center


University of California, San Francisco, Radiation Oncology

Medical School

Harvard Medical School


American Board of Radiology