Dr. Chen is an internationally-recognized expert in prostate cancer and bladder cancer. He has written several national guidelines for the American Urological Association (AUA) and the American Society of Clinical Oncology (ASCO) on the treatment of prostate cancer, and is frequently asked to speak across the US and internationally about the latest advances in taking care of prostate and bladder cancer patients. He has also written several textbooks and book chapters on prostate and bladder cancers -- which are read by urologists, radiation oncologists, medical oncologists and students internationally. Dr. Chen is a radiation oncologist with expertise in all forms of radiation treatment, including brachytherapy (seeds), external beam radiation (IMRT, IGRT), and stereotactic body radiation.