['Many investigators use prostate rebiopsy as an indicator of treatment efficacy and tumor response of localized prostate cancer for therapies in which the gland remains in situ. Because of the inherent sampling error of needle directed biopsies, however, some men will have a false-negative rebiopsy even if they have had no therapy or if the therapeutic intervention was unsuccessful in eradicating the malignancy. We evaluate the risk of a false-negative biopsy and the clinical factors that influence this risk.', 'A total of 90 patients undergoing radical prostatectomy for clinically localized disease underwent sextant biopsy of the prostate immediately after removal of the gland. Data collected included prostate specific antigen (PSA), hormonal status, age and biopsy core status.', 'Of the total study population 67.8% received neoadjuvant hormonal therapy. While all patients had pathologically confirmed adenocarcinoma within the prostatectomy specimen, 45.6% demonstrated a false-negative rebiopsy. Within a combined predictive model, PSA and hormonal status demonstrated a statistically significant effect on the false-negative rebiopsy rate. Predictive power of this combined model was high across the spectrum of risk for a false-negative rebiopsy.'] Is prostate rebiopsy a poor surrogate of treatment efficacy in localized prostate cancer?