Predicting the extent of prostate cancer using the combination of systematic biopsy and serum prostate-specific antigen in Japanese men

Objective To determine the utility of systematic biopsy alone or combined w ith an assay of serum prostate-specific antigen (PSA) level to predict the extent of prostate cancer in Japanese men. Patients and methods Thirty-two patients who were diagnosed as having clini cally organ-confined prostate cancer and who underwent prostatectomy were e valuated retrospectively for the results of systematic biopsy (percentage o f positive biopsy cores and cancer location), serum PSA and the pathologica l stage of whole-mount sections of the prostatectomy specimens. Results The incidence of extraprostatic disease (pT3N0M0 or N+) in patients with greater than or equal to 8 ng/mL of serum PSA and cancer in bilateral lobes was significantly higher than in those with <8 ng/mL PSA and cancer in one lobe (83% vs 30%, P=0.020). In those with more than half the biopsy cores positive, extraprostatic disease was significantly more common than i n those with less than half positive (93% vs 44%, P=0.0075); moreover, in p atients with more than half the cores positive and greater than or equal to 8 ng/mL serum PSA, it was significantly more common than in those with les s than half positive and <8 ng/mL of serum PSA (93% vs 27%, P=0.0021). Howe ver, the incidence of extraprostatic disease predicted by three variables ( cancer location, percentage positive biopsy cores and serum PSA) was not si gnificantly better than that predicted by two variables (percentage positiv e cores and serum PSA). Conclusions The combination of systematic biopsy and serum PSA may be usefu l in predicting extraprostatic cancer. Patients with greater than or equal to 8 ng/mL serum PSA and more than half the biopsy cores positive could avo id a prostatectomy because there is a high probability that they have extra prostatic disease.