Clinicopathological features of prostate cancer in Japanese men diagnosed on repeat transrectal ultrasound-guided biopsy

Clinicopathologic differences between prostate cancers detected during initial and repeat transrectal ultrasound-guided biopsy in Korea

Purpose

The aim of this study was to investigate clinicopathologic differences between prostate cancer (PCa) detected at initial and repeat transrectal ultrasound-guided prostate biopsy in a large Korean cohort.

Materials and Methods

From 2000 through 2012, a total of 7,001 patients underwent transrectal ultrasound-guided prostate biopsy at 6 centers in Daegu and Gyeongbuk provinces. Of these 7,001 patients, the initial biopsy was positive for PCa in 2,118 patients. Repeat biopsy was performed in 374 of the 4,883 patients with an initial negative finding and a persistently elevated prostate-specific antigen (PSA) level, nodules or asymmetry by digital rectal examination (DRE), high-grade prostatic intraepithelial neoplasia, or atypical small acinar proliferation. Numbers of biopsy cores varied from 6 to 12 according to center and biopsy date.

Results

Cancer was diagnosed in 2,118 of the 7,001 patients (30.3%) at initial biopsy and in 86 of the 374 patients (23.0%) at repeat biopsy. The repeat biopsy rate was 5.3%. Mean PSA values were 68.7±289.5 ng/mL at initial biopsy and 18.0±55.4 ng/mL at repeat biopsy (p<0.001). The mean number of cancer-positive cores per biopsy was 5.5±3.5 for initial biopsy and 3.0±2.9 for repeat biopsy (p<0.001). Mean Gleason score was 7.5±1.4 at initial biopsy and 6.6±1.3 at repeat biopsy (p<0.001). For detected cancers, the low-stage rate was higher for repeat biopsy than for initial biopsy (p=0.001).

Conclusions

Cancers detected at repeat biopsy tend to have lower Gleason scores and stages than cancers detected at initial biopsy. The present study shows that repeat biopsy is needed in patients with a persistently high PSA or abnormal DRE findings.

Characterization of prostate cancer detected at repeat biopsy

Background

The aim of this study was to investigate the characteristics of prostate cancer patients who were diagnosed at repeat biopsy and compare them to non-cancerous patients or patients who were diagnosed at initial biopsy.

Methods

We carried out a retrospective analysis of clinical and pathological data from 576 patients, which included data on the period of time from radical prostatectomy to biochemical failure.

Results

Cancer was diagnosed in 191 (33%) of 576 patients at initial biopsy and in 23 (18%) of 127 patients who underwent a repeat biopsy. Cut-off values of 0.80 and 0.30 for prostate specific antigen velocity (PSAV) and prostate specific antigen density (PSAD), respectively, were determined using ROC curve analysis. Based on these values, PSAV and PSAD were able to predict 94% (46 of 49) of negative repeat biopsies, indicating that these patients had undergone unnecessary repeat biopsies. Although the patients who were diagnosed at repeat biopsy had a higher rate of organ-confined tumor than those who were diagnosed at initial biopsy (73% and 44%, respectively; P = 0.041), there were no differences in the recurrence rate or the duration of biochemical failure-free survival between the two groups.

Conclusion

PSAV and PSAD may be useful indicators of the results of repeat biopsies. Although prostate cancer that was diagnosed at repeat biopsy was associated with a more favorable pathological profile, it was not associated with a better outcome after radical prostatectomy.