Feasibility of Using SPECT/CT Imaging to Map Lymphatic Drainage Patterns in Prostate Cancer Patients

The purpose of this study is to develop a practice procedure for lymphatic drainage mapping with the intent of providing a new tool that could potentially be used for radiation treatment planning. High-risk prostate cancer patients who are scheduled to be treated with intensity-modulated radiotherapy (IMRT) may be eligible to enroll in this study. 99mTc-sulfur nanocolloid, a radiopharmaceutical ("tracer") will be injected by a urologist using transrectal ultrasound guidance (TRUS)at the UCSF Urology Clinic. Participants will then undergo SPECT/CT imaging at the UCSF Nuclear Medicine Clinic. This study will evaluate the feasibility of transporting patients to the Nuclear Medicine Clinic for imaging within 1-3 hours after administration of 99mTc-sulfur nanocolloid.