Dr. Michael A. Geffin

Dr. Mark A. Preston is a urologic surgeon at Brigham and Women’s Hospital and Associate Professor of Surgery at Harvard Medical School. Dr. Preston received his Medical Degree from the University of Ottawa in Canada, where he also completed his residency training in Urology. He completed a three-year accredited fellowship in Urologic Oncology at Massachusetts General Hospital including a Masters of Public Health from the Harvard School of Public Health with a concentration in clinical effectiveness. He is board certified in Urology.Dr. Preston’s clinical interests include urologic oncology (bladder, kidney, prostate and testicular cancer) and minimally invasive surgery. Dr. Preston’s research focuses on the epidemiology of prostate and kidney cancer risk with an emphasis on predictive biomarkers and pharmacoepidemiology. Dr. Preston is highly rated in 19 conditions, according to our data. His top areas of expertise are Bladder Cancer, Muscle Invasive Bladder Cancer, Prostate Cancer, Cystectomy, and Prostatectomy.

Dr. Mossanen is a graduate of the University of California, Los Angeles (UCLA) in Los Angeles, CA and received his medical degree from the David Geffen School of Medicine at UCLA. He also holds a Master of Public Health from the Harvard T.H. Chan School of Public Health in Boston, MA. Dr. Mossanen completed a residency in Urology from the University of Washington in Seattle, WA followed by a fellowship in Urologic Oncology in the Combined Harvard Urologic Oncology Fellowship at Massachusetts General Hospital and Brigham and Women’s Hospital. Dr. Mossanen has been board certified by the American Board of Urology since 2020.His research and clinical interests include: bladder cancer, kidney cancer, kidney masses/cysts, laparoscopic surgery, penile cancer, prostate cancer, robotic surgery, testicular cancer. Dr. Mossanen is highly rated in 18 conditions, according to our data. His top areas of expertise are Bladder Cancer, Muscle Invasive Bladder Cancer, Penile Cancer, Cystectomy, and Nephrectomy.

Stephen Gillard is a Urologist in Plymouth, Massachusetts. Dr. Gillard is highly rated in 45 conditions, according to our data. His top areas of expertise are Perirenal Abscess, Boils, Urinary Tract Infection in Children, Ureteroscopy, and Prostatectomy.