Association of biopsy core number and location with pain in patients undergoing a transperineal prostate biopsy under local anaesthesia: a secondary analysis of the APROPOS trial.

BACKGROUND: APROPOS was a multicentre, randomized, blinded trial focus on investigating the perineal nerve block versus the periprostatic block in pain control for men undergoing a transperineal prostate biopsy. In the analysis reported here, the authors aimed to evaluate the association of biopsy core count and location with pain outcomes in patients undergoing a transperineal prostate biopsy under local anesthesia. METHODS: APROPOS was performed at six medical centers in China. Patients with suspected prostate cancer were randomized to receive either a perineal nerve block or a periprostatic block (1:1), followed by a transperineal prostate biopsy. The secondary analysis outcomes were the worst pain experienced during the prostate biopsy and postbiopsy pain at 1,6, and 24 h. RESULTS: Between 12 August 2020 and 20 July 2022, a total of 192 patients were randomized in the original trial, and 188 were involved in this analysis, with 94 patients per group. Participants had a median (IQR) age of 68 (63-72) and a median (IQR) prostate volume of 42.51 (30.04-62.84). The patient population had a median (IQR) number of biopsy cores of 15 (12-17.50), and 26.06% of patients had a biopsy cores count of more than 15. After adjusting the baseline characteristics, the number of biopsy cores was associated with the worst pain during the biopsy procedure in both the perineal nerve block group ( ß 0.19, 95% CI: 0.12-0.26, P <0.001) and the periprostatic block group ( ß 0.16, 95% CI: 0.07-0.24, P <0.001). A similar association was also evident for the postbiopsy pain at 1, 6, and 24 h. A lesser degree of pain in both groups at any time (r range -0.57 to -0.01 for both groups) was associated with biopsy cores from the peripheral zone of the middle gland, while other locations were associated with a higher degree of pain. In addition, the location of the biopsy core had less of an effect on pain during the biopsy (r range -0.01-0.25 for both groups) than it did on postbiopsy pain (r range -0.57-0.60 for both groups). CONCLUSIONS: In this secondary analysis of a randomized trial, biopsy core count and location were associated with pain in patients undergoing a transperineal prostate biopsy under local anesthesia. These results may be helpful for making clinical decisions about the anesthetic approach for scheduled transperineal prostate biopsies.

Perineal nerve block versus periprostatic block for patients undergoing transperineal prostate biopsy (APROPOS): a prospective, multicentre, randomised controlled study.

Background: We aimed to investigate perineal nerve block versus periprostatic block in pain control for men undergoing a transperineal prostate biopsy. Methods: In this prospective, randomised, blinded and parallel-group trial, men in six Chinese hospitals with suspected prostate cancer were randomly assigned (1:1) at the point of local anaesthesia to receive a perineal nerve block or periprostatic block and followed by a transperineal prostate biopsy. Centres used their usual biopsy procedure. Operators who performed anaesthesia were trained in both techniques before the trial and were masked to the randomised allocation until the time of anaesthesia and were not involved in the subsequent biopsy procedure and any assessment or analysis. Other investigators and the patients were masked until trial completion. The primary outcome was the level of the worst pain experienced during the prostate biopsy procedure. Secondary outcomes included pain (post-biopsy at 1, 6 and 24 h), changes in blood pressure, heart rate and breathing rate during the biopsy procedure, external manifestations of pain during biopsy, anaesthesia satisfaction, the detection rate of PCa and clinically significant PCa. This trial is registered on ClinicalTrials.gov, NCT04501055. Findings: Between August 13, 2020, and July 20, 2022, 192 men were randomly assigned to perineal nerve block or periprostatic block, 96 per study group. Perineal nerve block was superior for the relief of pain during the biopsy procedure (mean 2.80 for perineal nerve block and 3.98 for periprostatic block; adjusted difference in means -1.17, P < 0.001). Although the perineal nerve block had a lower mean pain score at 1 h post-biopsy compared with the periprostatic block (0.23 vs 0.43, P = 0.042), they were equivalent at 6 h (0.16 vs 0.25, P = 0.389) and 24 h (0.10 vs 0.26, P = 0.184) respectively. For the change in vital signs during biopsy procedure, perineal nerve block was significantly superior to periprostatic block in terms of maximum value of systolic blood pressure, maximum value of mean arterial pressure and maximum value of heart rate. There are no statistical differences in average value of systolic blood pressure, average value of mean, average value of heart rate, diastolic blood pressure and breathing rate. Perineal nerve block was also superior to periprostatic block in external manifestations of pain (1.88 vs 3.00, P < 0.001) and anaesthesia satisfaction (8.93 vs 11.90, P < 0.001). Equivalence was shown for the detection rate of PCa (31.25% for perineal nerve block and 29.17% for periprostatic block, P = 0.753) or csPCa (23.96% for perineal nerve block and 20.83% for periprostatic block, P = 0.604). 33 (34.8%) of 96 patients in the perineal nerve block group and 40 (41.67%) of 96 patients in the periprostatic block group had at least one complication. Interpretation: Perineal nerve block was superior to periprostatic block in pain control for men undergoing a transperineal prostate biopsy. Funding: Grant 2019YFC0119100 from the National Key Research and Development Program of China.