Oxaliplatin-induced Acute Neurotoxicity Recovers Between Repeat Infusion Cycles: An Axonal Excitability Repeated Multiple Measurements Study.

Abstract

Oxaliplatin, a platinum-based chemotherapy used in the treatment of colorectal cancer, induces acute neurotoxicity following infusion. The aim of this study was to establish whether alterations in axonal excitability develop progressively with higher cumulative doses and whether there is a recovery in motor axons after each cycle of treatment. Twenty consecutive patients with a colorectal cancer diagnosis, referred from the Oncology Department of Aretaieion Hospital of Athens, were enrolled in this study between October 2018 and May 2019. None of the participants had diabetes, alcohol abuse, known neuropathy or were previously treated with another neo-adjuvant therapy. Threshold Tracking techniques and Qtrac software were used for assessing axonal excitability in motor axons. Excitability recordings were undertaken before and immediately after the end of oxaliplatin infusion. Statistically significant changes were found (p<0.01) in axonal excitability (relative refractory period, refractoriness at 2 ms and 2.5 ms, sub-excitability and super-excitability) before and after oxaliplatin infusion. No statistically significant changes (p>0.05) were found in threshold electrotonus and strength-duration parameters before and after oxaliplatin infusion. We also did not find statistically significant differences (p>0.05) between means of excitability parameters before infusion at each cycle. Our study confirms oxaliplatin-induced acute neurotoxicity following infusion and suggests that motor axons recover between repeat infusion cycles.