A Prospective Study of Taxane-Induced Neuropathy with Breast Cancer: Proper Assessment Tool for Taxane-Induced Neuropathy

Background Many chemotherapeutic agents, especially taxanes, can induce peripheral neuropathy. Aim To evaluate the clinical characteristics of taxane-induced neuropathy (TIN) and determine the proper assessment tool for TIN in patients with breast cancer. Setting and Design Single-center, observational, prospective study. Methods and Material Forty-three patients with breast cancer treated with taxanes were prospectively enrolled. The reduced version of the Total Neuropathy Score (TNSr) was performed at baseline and 3 months after enrollment. TIN was diagnosed if the difference between the baseline and 3-month TNSr was greater than 1. In patients with TIN, the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire— Chemotherapy-Induced Peripheral Neuropathy (20-item scale (EORTC-CIPN20) was also assessed 3 months after enrollment. Results Thirty-seven out of 43 (86.0%) patients were diagnosed with TIN. Sensory symptoms (64.9%) were the most frequent abnormality, followed by autonomic symptoms (54.1%). No patients reported motor symptoms or motor weakness. The TNSr sensory symptom score positively correlated with that of the EORTC-CIPN20. Nerve conduction studies showed reduced nerve conduction velocities and amplitudes after taxane treatment compared to those before chemotherapy in all tested nerves; however, only three (8.1%) patients had sural sensory nerve action potential amplitude outside normal limits. Conclusions TIN was predominantly sensory with normal nerve conduction studies which is the main feature of small fiber neuropathy. A combination scale comprising of a clinician-based scale and a patient-reported questionnaire and specialized tests for small nerve fibers should be considered as proper assessment tools to evaluate TIN.