Testing the Effects of Low Dose Apalutamide on Prostate-Specific Antigen (PSA) Levels in Men Scheduled for Removal of the Prostate Gland

Inclusion Criteria: * Histologically confirmed organ-confined adenocarcinoma of the prostate (PCa) suitable for prostatectomy * Gleason score =\< (4+4), however no Gleason pattern 5 * Current serum PSA =\< 20 ng/ml * Age \> 18 years * Karnofsky \>= 70% * Leukocytes \>= 3,000/uL * Absolute neutrophil count \>= 1,500/uL * Platelets \>= 100,000/uL * Total bilirubin =\< 1.5 x institutional upper limit of normal (ULN) (note: in subjects with Gilbert's syndrome, if total bilirubin is \> 1.5 x ULN, measure direct and indirect bilirubin and if direct bilirubin is =\< 1.5 x ULN, subject may be eligible) * Aspartate aminotransferase (AST) (serum glutamic oxaloacetic transaminase \[SGOT\])/alanine aminotransferase (ALT) (serum glutamic pyruvic transaminase \[SGPT\]) \< 2.5 x institutional ULN * Creatinine \< 2 x institutional ULN * Thyroid stimulating hormone (TSH) within the institutional normal range * Willing to use adequate contraception (barrier method; abstinence; subject has had a vasectomy; or partner is using effective birth control or is postmenopausal) for the duration of study participation * Ability to understand and the willingness to sign a written informed consent document Exclusion Criteria: * Prior or ongoing hormonal treatment for prostate cancer including, but not limited to orchiectomy, antiandrogens, abiraterone, ketoconazole, or estrogens, or luteinizing hormone-releasing hormone (LHRH) agonists/antagonists. Men on stable doses of 5-alpha reductase inhibitors (…