TMaC Trial: A randomized, single-blinded, sham-controlled study evaluating effectiveness of repetitive transcranial magnetic stimulation for painful chemotherapy-induced peripheral neuropathy in colorectal cancer survivors.

Abstract

TPS251 Background: Chemotherapy-induced peripheral neuropathy (CIPN) is a prevalent and debilitating complication characterised by persistent pain and dysaesthesia. CIPN significantly impacts function and quality of life for survivors of colorectal cancer. Oxaliplatin is particularly associated with coasting and chronicity of symptoms, making management difficult. Effective treatments for CIPN-associated sensory disturbances remain limited. Transcranial magnetic stimulation (TMS), a non-invasive brain modulation technique, shows emerging promise for non-oncological neuropathic pain management. Therefore, this ongoing study aims to determine the analgesic and sensory-modulating potential of TMS in individuals living with chronic CIPN. Methods: This is an investigator-led phase II randomised controlled trial conducted in an academic setting, enrolling participants previously treated with oxaliplatin-containing chemotherapy for colorectal cancer. Participants are randomised (1:1) to receive TMS or sham stimulation over four weekly sessions using a figure-8 coil connected to two stimulators through a Bistim module (Magstim) in a posterior/anterior orientation. Neuronavigation system guided TMS stimulation, producing a paired-pulse motor evoked potential of 0.5-1.5 mV, is applied over the primary somatosensory cortex (S1), contralateral to the side of the most-affected extremity. Pain (primary outcome) and dysaesthesia are assessed pre and post each session using the Visual Analogue Scale (VAS) and weekly via the 8-item sensory CIPN (CIPN8) questionnaire. Pain and function are again assessed at 8-week and 6-month follow up. To date 20 out of the target recruitment of 40 has been achieved. This is the first study to investigate effectiveness of TMS in colorectal cancer. Clinical trial information: ACTRN12625000008426 .