['To evaluate the efficacy of TRUS guided 10-core biopsy strategy for Turkish patients who had biopsy of the prostate for the first time.', 'Between February 2001 and May 2003, 303 consecutive men with suspected prostate cancer were included in the study. Indications for TRUS guided prostate biopsy were: abnormal digital rectal examination and/or a serum PSA over 2.5 ng/ml. All of the patients underwent a 10-core biopsy protocol with additional core from the each suspicious area detected by TRUS. Besides the sextant technique, 4 more biopsies were obtained from the lateral peripheral zone. We aimed to analyze whether cancer detection improved with the extended versus the standard sextant biopsy in our series overall and in each subgroup.', 'Of 303 patients 94 (31%) were positive for prostate cancer. Median age and PSA of prostate cancer patients were significantly higher than of the non-cancer patients. Besides prostate volumes of the cancer patients were significantly lower than of the non-cancer ones. The cancer detection rates were 31% (94/303) and 23.1% (70/303) for the 10-core biopsy strategy and sextant biopsy strategies, respectively. Thus the 10-core biopsy technique increased cancer detection rate by 25.5% (24/94) for the whole group of patients. A statistically significant number of additional cancers were detected with 10-core biopsy strategy for all the subgroups of the patients. Furthermore 10-core biopsy protocol detected more cancers (at least 6.4%) than all the probable different combinations of 8-core biopsy protocols. Among the 94 cancer patients, biopsy from a suspicious area revealed cancer in 31.9% of them; however, in all of these patients cancer was already present in the 10-core biopsy. On the other hand, lesion biopsies revealed 5.7% additional cancers if sextant technique was used. There were only 3 (0.9%) serious complications requiring hospitalization and all 3 were infections controlled by appropriate antibiotics.'] Does an extended 10-core transrectal ultrasonography guided prostate biopsy protocol improve the detection of prostate cancer?