Deutenzalutamide and Hormone Therapy Before and After Surgery With Docetaxel Before Surgery for High-Risk Localized or Locally Advanced Prostate Cancer

POST-PC-01 is an investigator-initiated, prospective, multicenter, single-arm, open-label exploratory study. The rationale is to combine androgen receptor pathway inhibition and androgen deprivation with chemotherapy before definitive surgery, while limiting docetaxel exposure to the preoperative period. The study will generate preliminary evidence on antitumor activity, safety, and clinical feasibility; it is not designed to establish superiority over another treatment. The study uses a Simon minimax two-stage design. The first stage includes 16 participants in the prespecified primary efficacy decision analysis set. Enrollment will proceed to the second stage only if the first-stage results meet the predefined continuation criterion. The second stage adds 15 participants, for a total of 31 participants in the decision analysis set. The maximum enrollment of 37 allows limited replacement under protocol-defined circumstances unrelated to treatment efficacy or tolerability. Participants unable to undergo surgery because of disease progression or treatment toxicity are counted as nonresponders rather than replaced. The optional exploratory component is limited to pretreatment samples. It includes one peripheral blood collection of 20 mL for genetic analysis and the use of residual tissue from the diagnostic prostate biopsy. Tissue assessments include intraductal carcinoma of the prostate, BRCA1 and BRCA2 and other DNA repair-related gene alterations, and PTEN deletion or related abnormalities. No additional biopsy is performed for this component. Where samples and outcome data are available, associations between baseline pathological or genetic features and pathological response, recurrence, or progression will be explored descriptively. Participation requires an affirmative choice within the study informed consent form. Declining or withdrawing from this optional component does not affect participation in the study treatment and follow-up.