Highly Conformal, Hypofractionated, Focally Dose Escalated Post-Prostatectomy Radiotherapy

Overview

Background: Sometimes prostate cancer comes back after a person's prostate is removed. In this case, radiation is a common treatment. Radiation kills prostate cancer cells. It can be very effective. It is usually given in short doses almost every day for 6 or 7 weeks. Researchers want to see if a shorter schedule can be as effective. They want to see if that causes the same or fewer side effects. Usually, radiation is used to treat the entire area where the prostate was before surgery. In some patients, an area of tumor can be seen on scans. Researchers are also trying to see if they can give less dose to the area usually treated with radiation if the full dose is given to the tumor seen on scans. Objective: To find the shortest radiation schedule that people can tolerate without strong side effects. Eligibility: People at least 18 years old who have had a prostatectomy and will get radiation. Design: Participants will be screened with: * Medical history * Physical exam * Blood and urine tests * Scan that uses a small amount of radiation to make a picture of the body * Scan that uses a magnetic field to make an image of the body * Participants will provide documents that confirm their diagnosis. * Participants may have a scan of the abdomen and pelvis. Before they start treatment, participants will have another physical exam and blood tests. Participants will get radiation each day Monday through Friday. Treatment may last 2, 3, or 4 weeks. Participants may provide a tissue sample from a previous procedure for research. Participants will answer questions about their general well-being and function. About 4-5 weeks after they finish radiation treatment, participants will have a follow-up visit. They will be examined and give a blood sample. They will have 6 follow-up visits for the next 2 years.

BACKGROUND: Prostate cancer that recurs after prostatectomy (rising prostate-specific antigen (PSA) with no evidence of metastatic disease is often treated with radiation to the entire prostate bed to a dose of 66-72 Gray (Gy) over 6-7 weeks. This treatment can provide PSA control in approximately 75% of patients but may have associated genitourinary and gastrointestinal toxicity due to irradiation of the rectum, small bowel, and bladder. Imaging of prostate cancer has improved to the extent that recurrent disease is often identified in the prostate bed or in other pelvic sites. The current standard is to irradiate the entire prostate bed to the total dose. This trial will test the tolerability of accelerated treatment designed to yield a similar rate of late toxicity. In addition, in patients with visible tumor, it will test the feasibility of delivering a lower dose to the prostate bed and an integrated boost (simultaneous) to the visible tumor to allow a higher dose to visible tumor than can be delivered with standard approaches. OBJECTIVE: \- Define the maximum tolerated dose (MTD) hypofractionation of image guided, focally dose escalated post-prostatectomy radiation. ELIGIBILITY: * PSA recurrence after prostatectomy or indications for adjuvant radiation after prostatectomy. * No evidence of distant metastases of prostate cancer (pelvic lymph nodes are allowed). * Age greater than or equal to 18 years old * Eastern Cooperative Oncology Group (ECOG) performance status less than or equal to 1 DESIGN: This is a Phase I trial of hypofractionated focal dose escalation with reduced dose prostate bed irradiation using image and pathologic guidance. The prostate bed will be treated with hypofractionated radiation and areas in the prostate bed or pelvis shown to have tumor on biopsy or with advanced imaging studies will be treated with an integrated boost to visible tumor. The treatment duration will be decreased sequentially in three Dose Level groups. Quality of life and functional outcomes such as urine, bowel, and erectile function will be assessed with questionnaires. A maximum of 48 patients will be enrolled.