'Pain-free TRUS B': a phase 3 double-blind placebo-controlled randomized trial of methoxyflurane with periprostatic local anaesthesia to reduce the discomfort of transrectal ultrasonography-guided prostate biopsy (ANZUP 1501)

Current Approach to Complications and Difficulties during Transrectal Ultrasound-Guided Prostate Biopsies

Prostate cancer is one of the most common male malignancies worldwide. It affects middle-aged men (45-60 years) and is the leading cause of cancer-related mortality in Western countries. The TRUS (trans rectal ultrasound)-guided prostate biopsy has been a standard procedure in prostate cancer detection for more than thirty years, and it is recommended in male patients with an abnormal PSA (prostate-specific antigens) or abnormalities found during digital rectal examinations. During this procedure, urologists might encounter difficulties which may cause subsequent complications. This manuscript aims to present both the complications and the technical difficulties that may occur during TRUS-guided prostate biopsy, along with resolutions and solutions found in the specialized literature. The conclusions of this manuscript will note that the TRUS-guided prostate biopsy remains a solid, cost-efficient, and safe procedure with which to diagnose prostate cancer. The complications are usually self-limiting and do not require additional medical assistance. The difficulties posed by the procedure can be safely overcome if there are no other available alternatives. Open communication with the patients improves both pre- and post-procedure compliance.

Literature review on the use of methoxyflurane in the management of pain in cancer-related procedures

INTRODUCTION

Self-administered methoxyflurane, also known as Penthrox, at a sub-anesthetic dose is a short-term, fast-acting, and safe analgesic that may provide suitable pain relief for cancer patients. This review aims to compile the existing evidence on methoxyflurane and its efficacy in reducing pain during cancer-related procedures.

METHODS

A literature search was conducted through OVID Medline and Embase. The search was limited to articles published between 2012 and 2021 and studies were included if they assessed the efficacy of methoxyflurane to reduce pain in cancer-related procedures. All types of cancer were included.

RESULTS

The literature search yielded seven studies published between 2012 and 2021. The studies analyzed assessed methoxyflurane use in prostate biopsy, colonoscopy, removal of brachytherapy rods, and bone marrow biopsy. Various research designs were employed, including three randomized controlled trials, two prospective observational studies, one retrospective, and one non-randomized controlled trial. In all, methoxyflurane has a demonstrated ability to reduce pain in these procedures.

CONCLUSION

In the limited studies available in evaluating the efficacy of methoxyflurane for reducing procedural pain during cancer-related procedures, all have demonstrated clinical equivalency or superiority. Pain relief appears to be equivalent however methoxyflurane overcomes the standard limitations of respiratory sedation and has demonstrated quicker procedural recovery times than traditional sedation methods. The accumulated data to date supports the use of methoxyflurane which can supplement or supplant current methods of analgesia in cancer-related procedures.

Comparison of intrarectal heated lidocaine gel and periprostatic nerve block for pain control in transrectal ultrasound-guided prostate biopsy: A randomized controlled non-inferiority trial

Background

To investigate whether intrarectal local anesthesia with heated lidocaine gel (IRLAH) is non-inferior to periprostatic nerve block (PNB) for reducing pain in patients undergoing transrectal ultrasound (TRUS)-guided prostate biopsy.

Methods

We performed a randomized controlled non-inferiority trial with 100 participants who underwent systematic TRUS-guided, 12-core prostate biopsy from August 2019 to July 2020. These participants were randomly assigned to a group receiving intrarectal local anesthesia with 20 mL of heated (40°C) 2% lidocaine gel (n = 50) or PNB (n = 50). The primary outcome was a pain score on a 0-10 visual analogue scale (VAS) at four time points with the non-inferiority margin of 1; VAS-1: during local anesthesia application; VAS-2: during probe insertion; VAS-3: during biopsy; VAS-4: 30 minutes after the procedure. The secondary outcome included complications during and after the procedure.

Results

The IRLAH group (0.1) met non-inferiority as well as superiority criteria for mean VAS-1 score vs. the PNB group (2.33) (P < 0.001), as the difference (95% confidence interval [CI]) between the two groups was -2.23 (-2.66 to -1.79) and the upper bound of the 95% CI were both below the prespecified non-inferiority margin and below zero. For mean VAS-3 score, the difference (95% CI) was 0.3 (-0.38 to 0.98) and the upper bound of the 95% CI did not exceed the predefined non-inferiority margin indicating that IRLAH was non-inferior (IRLAH group, 3.44; PNB group, 3.14). Also, non-inferiority was shown for pain scores at VAS-2 and VAS-4. There were no significant differences in complications.

Conclusion

IRLAH is a noninvasive and non-inferior alternative to PNB for pain control in TRUS-guided prostate biopsy without increased risk of complications.