Objective To determine whether data obtained from preoperative prostate needle biopsy can predict the laterality of significant cancer and positive surgical margins on final-specimen pathology after laparoscopic radical prostatectomy (LRP). Patients and methods Data from 490 patients undergoing LRP by one surgeon were reviewed retrospectively. The demographic characteristics, intraoperative data and pathological results were analysed. Univariate and multivariate analyses were used to determine which factors before and during LRP influenced the positive surgical margin status. Results There was only minor agreement between the laterality of positive needle biopsies and laterality of any cancer and significant cancer on final-specimen pathology (κ = 0.135 and 0.151, respectively). This was irrespective of the number of needle cores obtained or final-specimen Gleason grade. Similarly, the laterality of dominant cancer on needle biopsy had only a minor agreement with the location of positive surgical margins (κ = 0.050) and fair agreement with the location of extracapsular extension on final-specimen pathology (κ = 0.235). Conclusions Preoperative needle biopsy data have only a minor correlation with the laterality of significant cancer and positive surgical margins at final pathology of LRP specimens. Recognition of this fact, and the frequent bilaterality of significant cancer, with its potential for contralateral positive surgical margins even when the biopsies are positive only unilaterally, is an important consideration when planning nerve-sparing, and potentially for focal therapy. © 2009 BJU INTERNATIONAL.