Single positive core prostate cancer in a 12-core transrectal biopsy scheme: clinicopathological implications compared with multifocal counterpart.

PURPOSE

The incidence of single positive core prostate cancer at the time of biopsy appears to be increasing in the prostate-specific antigen (PSA) era. To determine the clinical implication of this disease, we analyzed surgical and pathological characteristics in comparison with multiple positive core disease.

MATERIALS AND METHODS

Among 108 consecutive patients who underwent robotic radical prostatectomy following a diagnosis of prostate cancer based on a 12-core transrectal biopsy performed by the same method in a single institute, outcomes from 26 patients (Group 1) diagnosed on the basis of a single positive biopsy core and from 82 patients (Group 2) with multiple positive biopsy cores were analyzed.

RESULTS

The preoperative PSA value, Gleason score, prostate volume, and D'Amico's risk classification of each group were similar. The proportion of intermediate+highrisk patients was 69.2% in Group 1 and 77.9% in Group 2 (p=0.22). Total operative time and blood loss were similar. Based on prostatectomy specimens, only 3 patients (11.5%) in Group 1 met the criteria for an indolent tumor (7.31% in Group 2). Although similarities were observed during preoperative clinical staging (p=0.13), the final pathologic stage was significantly higher in Group 2 (p=0.001). The positive-margin rate was also higher in Group 2 (11.5% vs. 31.7%, p=0.043). Despite similarity in upstaging after prostatectomy in each group (p=0.86), upgrading occurred more frequently in Group 1 (p=0.014, 42.5% vs. 19.5%). No clinical parameters were valuable in predicting upgrading.

CONCLUSIONS

Most single positive core prostate cancer diagnoses in 12-core biopsy were clinically significant with similar risk stratification to multiple positive core prostate cancers. Although the positive-margin rate was lower than in multiple positive core disease, an increase in Gleason score after radical prostatectomy occurred more frequently.