Gonadotropin-releasing Hormone Analog

This phase II trial compares giving estrogen with an androgen receptor signaling inhibitor to standard of care luteinizing hormone-releasing hormone (LHRH) analogues with an androgen receptor signaling inhibitor for improving quality of life for patients with hormone sensitive prostate cancer that is newly diagnosed or that has come back after a period of improvement (recurrent) and has spread from where it first started (primary site) to other places in the body (metastatic). Standard prostate cancer treatment decreases hormone levels, specifically estrogen, in the body which can lead to hot flashes, fatigue, decreased bone health, and cardiovascular and metabolic dysfunction. Transdermal estrogen may help to alleviate these symptoms. Androgen receptor signaling inhibitors work by blocking the effects of androgen (a male reproductive hormone) to stop the growth and spread of tumor cells. LHRH analogues are a type of androgen deprivation therapy that blocks the use of androgen by the tumor cells. Giving estrogen with androgen receptor signaling inhibitor may improve quality of life in men with newly diagnosed or recurrent metastatic hormone sensitive prostate cancer.

This phase II trial tests the accuracy of functional imaging (FFNP)-positron emission tomography (PET)/computed tomography (CT) to predict response to abemaciclib plus endocrine therapy. Abemaciclib is a drug used to treat certain types of hormone receptor positive (HR+), HER2 negative breast cancer. Abemaciclib blocks certain proteins, which may help keep tumor cells from growing. Endocrine therapy adds, blocks, or removes hormones that can cause cancer to grow. FFNP PET imaging is a form of x-ray that uses FFNP as an imaging agent that may provide more precise information about the location of tumors that "light up" with FFNP than a PET scan alone can provide.