Antiandrogen Therapy and Radiation Therapy With or Without Docetaxel in Treating Patients With Prostate Cancer That Has Been Removed by Surgery

Inclusion Criteria: * Patients post-prostatectomy with baseline Gleason \>= 7 (per prostatectomy pathology) * Baseline PSA prior to start of androgen deprivation therapy nadir \>= 0.2 ng/ml (post-operative value is never undetectable) obtained prior to step 1 registration * Baseline testosterone level obtained post-prostatectomy prior to start of androgen deprivation therapy and prior to step 1 registration * Pathologically (histologically) proven diagnosis of adenocarcinoma of the prostate as confirmed at time of prostatectomy; prostatectomy must have been performed within 365 days (1 year) prior to step 1 registrationand any type of radical prostatectomy is permitted, including retropubic, perineal, laparoscopic or robotically assisted; (please note: Prior ablative treatment for benign prostatic hypertrophy or focal high-intensity focused ultrasound therapy \[HIFU\] prior to prostatectomy is allowed) * Surgical formalin-fixed paraffin-embedded (FFPE) specimen must be available for submission to GenomeDx for genomic analysis on DECIPHER GRID platform * Please note: If a patient already has a Decipher risk score and meets all of the other eligibility criteria, the patient is eligible to be registered; however, the Decipher risk report will need to be submitted to GenomeDx for validation * Prior androgen deprivation (luteinizing hormone-releasing hormone \[LHRH\] agonist and/or non-steroidal anti-androgen) is allowed if: * Androgen deprivation therapy was initiated with…