Clinical data
The prospective, randomized controlled study was done in our hospital from July 2016 to August 2017. Ethics clearance was obtained from the Clinical Medical College of the Yangzhou University.
Study inclusion criteria included: digital rectal examination findings nodules; and/or ultrasound or magnetic resonance imaging revealings suspicious of prostate cancer; and/or PSA4 ~ 10 ng/ml with an abnormal free/total PSA or PSA density; and/or PSA > 10 ng/ml. Exclusion criteria were chronic pelvic pain syndrome, chronic prostatitis, previous prostate biopsies, allergy to local anesthetic, bleeding disorder, pathological rectum, active urinary tract infection and taking analgesic medications. All patients signed a written informed consent before prostate biopsy. Assisted by a computer program, an independent researchers used a random number table to randomly divide the patients into three groups. The patients of group-1 received prostate capsule local anesthesia (PLA), group-2 received PNB in addition to PLA, and group-3 received PLA along with a PPB. Regarding the grouping assignment, the patients were unaware the details.
Biopsy procedure
The biopsy device included: A biplanar TRUS probe (Flex focus 1202; BK, Naerum, Denmark), brachytherapy stepping unit (Fixer, template, stepper) (Mick Radio-Nuclear Instruments, Mount Vernon, NY, USA), Bard biopsy gun (Bard MCl 820) and an 18-gauge biopsy needle.
Before prostate biopsy, complete blood cell count with differentiation, coagulation test and comprehensive metabolic panel were routinely performed. The patients were given oral intestinal clearance drugs one day before operation and emptied their stools on the morning of operation.
The patients were placed in a lithotomy position and underwent a conventional digital rectal examination. The TRUS probe was fixed on the brachytherapy stepping unit and was placed into the rectum. Then, the patients received the following anesthesia:
Group-1 (PLA): under the guidance of TRUS, the projection range of prostate in perineal skin was observed. In an area larger 0.5 cm than this range, infiltration anesthesia of perineal skin used 10 ml of 1% lidocaine. Then infiltration anesthesia was performed on the apex of the prostate. At the 1, 3, 5, 7, 9 and 11 o’clock of the area which prostate apex projected in the perineal skin, the syringe enters from these points and injected 12 ml of 1% lidocaine near the apex of the prostate.
Group-2 (PLA + PNB): for PNB, by rotating the TRUS probe, the vessels in the prostatic neurovascular bundle (NVB) can be observed at the prostate-bladder-seminal vesicle angle. Therefore, the NVB can be located by blood vessels. In the region of NVB, ANSll 0.5 mm ∗ 112 mm spinal needle was used to inject 5 ml of 1% lidocaine to perform PNB. The same was done for the other side (Fig. 1).
Group-3 (PLA + PPB): for PPB, under color Doppler ultrasound guidance, pelvic plexus was positioned which situated in the lateral to the apex of bilateral seminal vesicles. Then, in the area of the pelvic plexus, 5 ml 1% lidocaine was injected (Fig. 2).
To avoid injecting local anesthetic into the vessels, the syringe was aspirated before injecting local anesthetic in the three groups. After 5 min, prostate biopsies were performed.
Pain and complication assessment
Pain was evaluated by the visual analog scale (VAS; 0, none; 10, intolerable pain), and satisfaction was quantified using a visual numeric scale (VNS; 0, terrible; 4, perfect); only integers were allowed [23, 24]. Another independent resident and the patients were ‘blinded’ to the type of anesthesia given. The resident explained the VAS and VNS to the patients and requested them to rate their level of pain or satisfaction. VAS scores and VNS scores had two time points: VAS-1 and VNS-1 during the biopsy procedure, and VAS-2 and VNS-2 at 30 min after the procedure. The patients recorded the VAS and VNS scores without any other assistance.
Patients were given a nonvalidated self-administered questionnaire about complications such as hematuria, hemospermia, urinary retention and infection.
Statistical analysis
Epi Info™ 7 (WHO, Geneva, Switzerland) was used for sample size calculation. 95% CI, 5% α error, 80% power and 90% population proportion were set. It was estimated that at least 42 men would be needed for each of the three groups. And according to the 20% predicted clinical missed follow-up rate, at least 51 patients in each group were required.
Data analysis was performed using SPSS (version 19.0; IBM Corp, Armonk, NY) statistical software. The VAS scores and VNS scores were shown as mean ± SD and were compared using the one-way ANOVA test. And the rates of complications were compared using χ2 test. P < 0.05 was considered statistically significant.