Corneal Confocal Microscopy Detects Small Fibre Neuropathy in Patients with Upper Gastrointestinal Cancer and Nerve Regeneration in Chemotherapy Induced Peripheral Neuropathy

There are multiple neurological complications of cancer and its treatment. This study assessed the utility of the novel non-invasive ophthalmic technique of corneal confocal microscopy in identifying neuropathy in patients with upper gastrointestinal cancer before and after platinum based chemotherapy. In this study, 21 subjects with upper gastrointestinal (oesophageal or gastric) cancer and 21 healthy control subjects underwent assessment of neuropathy using the neuropathy disability score, quantitative sensory testing for vibration perception threshold, warm and cold sensation thresholds, cold and heat induced pain thresholds, nerve conduction studies and corneal confocal microscopy. Patients with gastro-oesophageal cancer had higher heat induced pain (P = 0.04) and warm sensation (P = 0.03) thresholds with a significantly reduced sural sensory (Prd cycle of chemotherapy, there was no change in any measure of neuropathy, except for a significant increase in CNFL (P = 0.003). Corneal confocal microscopy detects a small fibre neuropathy in this cohort of patients with upper gastrointestinal cancer, which was related to disease severity. Furthermore, the increase in CNFL after the chemotherapy may indicate nerve regeneration.