Taxane-induced peripheral neuropathy: differences in patient report and objective assessment

Purpose: Chemotherapy-induced peripheral neuropathy (CIPN) is a dose-limiting side-effect of neurotoxic cancer treatment impacting on long-term quality of life. Symptoms include numbness, tingling, and pain, affecting the distal extremities. However, patients often report symptoms discrepant from the expected symmetrical distribution and the degree of concurrence with objective assessment remains ill-defined. This study aimed to investigate severity and symmetry of neuropathy symptoms to enable comparison of objective measures and patient report.

Methods: Forty-five taxane-treated patients (F = 43, 66 ± 1.5 years, 19 months post-treatment) completed bilateral neuropathy assessments via clinical examination, sensory nerve conduction studies (NCS), and patient questionnaires. The laterality index (LI) was calculated as a ratio of smaller to larger side-to-side differences.

Results: Neuropathy was reported by 89% of the cohort. On clinical examination, 83% had ≥ 2 abnormalities, with 38-35% having upper or lower limb sensory amplitudes below normative range. Thirty-five percent indicated side-to-side symptom asymmetry; however, there was no significant asymmetry evident on clinical examination (LI Asym = .60 ± .10, Sym = .76 ± .05, NS) and no difference in side-to-side NCS (median LI:Asym = .69 ± .06, Sym = .81 ± .04, NS; Sural LI:Asym = .80 ± .04, Sym = .81 ± .04, NS). Accordingly, there was no statistical association between patient-reported and objective assessment of side-to-side asymmetry, suggesting discordance between patient experience and objective assessment. Similarly, discrepancies in symptom severity between hands and feet were reported by 32% of the cohort. However, patients reporting differences in symptom severity between the hands and feet were just as likely to present with comparable assessments as to demonstrate objective discrepancies.

Conclusions: Discrepancies may exist between the patient experience of CIPN and objective assessments. Understanding these discrepancies may help to elucidate underlying mechanisms and better inform treatment strategies.