Abstract
Objective: We evaluated the differences in pathologic findings and outcomes in patients undergoing radical retropubic prostatectomy (RRP) for localized prostate cancer diagnosed by either extended or non-extended prostate needle biopsy techniques.
Patients and Methods: Two hundred and seventy eight men with the diagnosis of localized prostate cancer using needle biopsies who underwent RRP were evaluated. Two study groups were identified: the first consisted of 123 patients diagnosed with prostate cancer by the use of extended needle biopsies (10 or more biopsy cores), and the second group consisted of 155 patients diagnosed with cancer by non-extended needle biopsies (9 or less biopsy cores). Median time of follow-up was 45 and 50 months, respectively. Biopsy and RRP specimen characteristics and outcome were compared between the two groups.
Results: Patients in the extended biopsy group had a median of 12 biopsy cores Interquartile range (IQR, 10–13; range, 10–16) with a mean of 2.7 cores positive for cancer (median 14% cores positive for cancer; IQR 8–30%). Patients in the non-extended biopsy group had a median of 6 cores (IQR, 6–8; range, 1–9) and a mean of 2.2 positive cores (median of 33% cores positive for cancer, IQR 16–50%) Needle biopsy results for Gleason score and presence of perineural invasion were similar in both groups. In the RRP specimens, the prostate weight was higher in the extended needle biopsy group There was a significant difference in the number of total sections required to histologically define the cancer; 45% of patients required >8 slides in the extended biopsy group whereas only 36% in the non-extended biopsy group required >8 slides However, there were no significant differences between the two groups in terms of pathological stage, surgical Gleason score, perineural invasion, capsular penetration, positive margins, seminal vesicle involvement or lymph node involvement. Biochemical disease-free recurrence was 11% (14/123) and 14% (22/155) in the extended and non-extended biopsy groups, respectively
Conclusions: Using the extended prostate biopsy technique, we detected a lower percent of positive cores for cancer on the needle biopsy. After RRP, a higher number of histological slides had to be processed for detection of prostate cancer after RRP. These findings suggest that lower volume prostate cancers are being detected by using the extended needle biopsy technique. However, these data show that extended biopsies detect cancers that after the RRP behave the same, by grade, stage and recurrence as those detected by non-extended biopsies. Longer follow-up and the presence of other predictors of cancer recurrence may differentiate the outcome of both groups of patients.