Zonal biopsy in the detection of prostate cancer in Japanese men.

To reduce sampling error as much as possible in the detection of prostate cancer, extensive transition zone sampling, in addition to the standard sextant random systematic biopsies, has been proposed. Improved biopsy techniques should make possible earlier and more effective detection of prostate cancer in a population where the incidence is low. Evaluation of such biopsies for elderly Japanese males is thus required. A total of 344 Japanese patients participated in this study. They underwent two transition zone biopsies in addition to systematic biopsy. Fifty-five of the 344 patients (16.0%) had cancer. Both biopsies were positive in 33 patients (60.0%), the standard systematic sextant biopsy alone demonstrated cancer in further 20 (36.4%) and the transition zone biopsy alone was positive in two others (3.6%). The two patients with cancer only in the transition zone biopsy cores had palpable abnormality and elevated prostate specific antigen. None of those with palpably benign glands or those with prior negative biopsies had cancer in the transition zone. Two additional cores from the transition zone led to no increase in morbidity of biopsy. Transition zone biopsy would not significantly contribute to the detection of prostate cancer in the present Japanese elderly male population. Though possibly of some value for certain patients, this biopsy does not warrant routine use.