Relugolix

This phase II trial studies how well a short course of androgen deprivation therapy (ADT) with relugolix works in increasing expression of prostate-specific membrane antigen (PSMA) and improving diagnostic imaging with PSMA positron emission tomography (PET)/computed tomography (CT) in patients with high risk or very high risk prostate cancer. PSMA PET/CT has become the standard of care in imaging for high-risk prostate cancer. However, a limitation of PSMA PET/CT is its ability to detect cancer that has spread to the lymph nodes. PSMA is a protein that is usually found on the surface of normal prostate cells but is found in higher amounts on prostate tumor cells. Studies have shown that expression of PSMA is regulated by androgens (male reproductive hormones). Relugolix binds to gonadotropin-releasing hormone receptors in the pituitary gland, which blocks the pituitary gland from making the hormones follicle-stimulating hormone and luteinizing hormone. This causes the testicles to stop making testosterone. Relugolix may stop the growth of tumor cells that need testosterone to grow. PSMA PET/CT is an imaging procedure that is used to help find prostate tumor cells in the body. For this procedure, a cell-targeting molecule linked to a radioactive substance (flotufolastat F 18 in this trial) is injected into the body and travels through the blood. It attaches to PSMA that is found on the surface of prostate tumor cells. PET/CT scanners detect high concentrations of the radioactive molecule and shows where the prostate tumor cells are in the body. Giving a short course of ADT with relugolix may increase PSMA expression to detect smaller areas of prostate cancer that were not previously detected.

This phase III trial tests two questions by two separate comparisons of therapies. The first question is whether enhanced therapy (apalutamide in combination with abiraterone + prednisone) added to standard of care (prostate radiation therapy and short term androgen deprivation) is more effective compared to standard of care alone in patients with prostate cancer who experience biochemical recurrence (a rise in the blood level of prostate specific antigen \[PSA\] after surgical removal of the prostate cancer). A second question tests treatment in patients with biochemical recurrence who show prostate cancer spreading outside the pelvis (metastasis) by positron emission tomography (PET) imaging. In these patients, the benefit of adding metastasis-directed radiation to enhanced therapy (apalutamide in combination with abiraterone + prednisone) is tested. Diagnostic procedures, such as PET, may help doctors look for cancer that has spread to the pelvis. Androgens are hormones that may cause the growth of prostate cancer cells. Apalutamide may help fight prostate cancer by blocking the use of androgens by the tumor cells. Metastasis-directed targeted radiation therapy uses high energy rays to kill tumor cells and shrink tumors that have spread. This trial may help doctors determine if using PET results to deliver more tailored treatment (i.e., adding apalutamide, with or without targeted radiation therapy, to standard of care treatment) works better than standard of care treatment alone in patients with biochemical recurrence of prostate cancer.

The purpose of this research study is to test the efficacy of ADT on prostate-specific membrane antigen (PSMA), a marker of prostate cancer, before and after scheduled ADT. Follow up will be 48 months your prostate removal to do a blood test and log if any new or worsening symptoms have occurred as a part of your standard-of-care (SOC).

This study is testing the way that approved androgen deprivation therapy treatments, Leuprolide and Relugolix, for prostate cancer affect quality of life, blood levels, cholesterol, and blood sugar. The drugs are already standard treatment for people with prostate cancer, and the drugs will be used as described in their label. The names of the study drugs involved in this study are: * Leuprolide (type of ADT) * Relugolix (type of ADT)

This phase II trial studies the effects of stereotactic body radiation therapy (SBRT) and the timing of treatment with androgen receptor pathway inhibitor (ARPI) plus androgen deprivation therapy (ADT) in treating patients with hormone sensitive prostate cancer that has spread from where it first started to other places in the body (metastatic), and that has come back after a period of improvement (recurrent). It also studies the effects of salvage radiation therapy (sXRT) on prostate cancer and to see if radiation to the pelvis helps prevent prostate cancer from spreading elsewhere. SBRT is a type of external radiation therapy that uses special equipment to position a patient and precisely deliver radiation to tumors in the body (except the brain). The total dose of radiation is divided into smaller doses given over several days. This type of radiation therapy helps spare normal tissue. Androgen can cause the growth of prostate cells. ADT lowers the amount of androgen made by the body. This may help stop the growth of tumor cells that need androgen to grow. Androgen receptor pathway inhibitors work by blocking the effects of androgen to stop the growth and spread of tumor cells. sXRT is a targeted radiation treatment for the prostate, typically given when cancer possibly returns after surgery or radiation. Its goal is to destroy any tumor cells in the area. Giving SBRT alone with watchful waiting may be as effective in treating prostate cancer as giving SBRT together with ARPI and ADT and sXRT may be effective in treating prostate cancer and preventing it from spreading elsewhere.