Differences in Postoperative Pathological Outcomes between Prostate Cancers Diagnosed at Initial and Repeat Biopsy

The Impact of Repeat Prostate Biopsies on Oncologic, Pathological and Perioperative Outcomes after Radical Prostatectomy

PURPOSE

The impact of repeat biopsy sessions on radical prostatectomy remains controversial regarding perioperative, pathological and oncologic outcome.

MATERIALS AND METHODS

We analyzed the records of 12,624 patients who underwent radical prostatectomy from 2007 to 2013. The association of the number of biopsy sessions (range 1 to 3 or more) with pathological outcomes and perioperative complications was analyzed using the Wilcoxon matched pair test. To test the association between biopsy sessions and biochemical recurrence-free survival we used Kaplan-Meier curves and multivariable Cox regression analysis.

RESULTS

Of the patients 89.2% had 1 biopsy session, 7.4% had 2 sessions and 3.4% had 3 or more sessions. Median followup was 36.6 months. In patients with 1, 2 and 3 or more biopsy sessions prostate volume (38, 44 and 45 ml) and prostate specific antigen (6.7, 7.6 and 10.1 ng/ml, respectively) were greater (each p <0.001). The perioperative outcome was more favorable. Patients with 1, 2 and 3 or more biopsy sessions more often had organ confined tumors (67.6%, 72.1% and 72.9%, p = 0.003) and higher tumor volume (3.1, 3.0 and 3.6 ml, p <0.001) but a lower tumor percent (7.5%, 3.7% and 2.4%, respectively, p <0.001). More biopsy sessions were associated with fewer lymph node metastases (1, 2 and 3 sessions 0.23, 0.13 and 0.17, respectively, p <0.001). Gleason score and surgical margin status did not differ. The overall biochemical recurrence rate was 18.9% and it was comparable among the biopsy groups. No association was found between the number of biopsies and biochemical recurrence.

CONCLUSIONS

Patients with multiple biopsy sessions experience a slightly more favorable pathological outcome without an impact on the oncologic outcome. The perioperative outcome was more favorable in patients with multiple biopsies.

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.

Are more low-risk prostate cancers detected by repeated biopsy? A retrospective pilot study

PURPOSE

We hypothesized that there might be a higher incidence of low-risk prostate cancer (PCa) in men diagnosed at a repeated biopsy. Thus, we investigated differences in clinicopathological results of PCa after primary and repeated biopsy.

MATERIALS AND METHODS

We retrospectively reviewed patients diagnosed with PCa at a primary or repeated biopsy from January 2004 to April 2011. Patients were stratified into primary biopsy and repeated biopsy groups. We analyzed prostate-specific antigen, clinical stage, Gleason score (GS), positive core ratio, and low-risk group by using D'Amico classification. We also investigated GS upgrading and upstaging after radical prostatectomy (RP).

RESULTS

Among 448 primary and 37 repeated biopsy PCa patients, 82 (group 1) and 25 (group 2) underwent RP. The percentage of low-risk patients did not differ significantly between the groups. The positive biopsy core ratio was significantly lower in group 2 (p=0.009). The percentages of GS upgrading and upstaging were 42.7% and 47.6% in group 1, respectively (p=0.568), and 48.0% and 52.0% in group 2, respectively (p=0.901). In the analysis of low-risk patients, GS upgrading and upstaging were not significantly different between the groups (p=0.615 and p=0.959, respectively).

CONCLUSIONS

A lower positive core ratio may imply a small volume of PCa and possibly insignificant PCa in the repeated biopsy group. However, no significant differences were observed for the ratio of low-risk cancers, GS upgrading, or upstaging between the groups. Therefore, PCa diagnosed at a repeated biopsy is not an additional indication for active surveillance.