Detailed Description: 1. Identify novel exosomal RNA signatures at pretreatment that predict response to ADT. The study team will collect blood samples from patients with systemic disease pretreatment (at enrollment), three months post-treatment and at the time of progression of disease (or at two years post-ADT for patients still in remission at that time point) and then perform next-generation sequencing using serum exosomal RNAs derived from these patients. The investigators plan to identify exosomal RNAs signatures that change between pretreatment (at enrollment) and during treatment (at three months) and further explore the effect of these changes on disease response. The investigators also plan to compare exosomal RNA levels between patients relapse within the first two years versus those in remission at two years. Among patients with progression, the investigators plan to compare exosomal RNA signatures at progression of disease to signatures at pretreatment and during treatment. 2. Validate exosomal RNA markers that predict response to ADT by real-time RT-PCR. Secondary objectives: Selected RNAs, identified through the above process will be validated using real-time RT-PCR assay to test reproducibility of RNA sequencing results. The investigators expect to select and validate approximate five RNA markers that predict duration of response to ADT.