Characterising vincristine-induced peripheral neuropathy in adults: symptom development and long-term persistent outcomes.

BACKGROUND: Decades following the introduction of vincristine as treatment for haematological malignancies, vincristine-induced peripheral neuropathy (VIPN) remains a pervasive, untreatable side-effect. However there remains a gap in understanding the characteristics of VIPN in adults. This study presents a comprehensive phenotyping of VIPN.

METHODS: Adult patients (n = 57; age = 59.8 ± 14.6) were assessed cross-sectionally following completion of vincristine (months post treatment = 16.3 ± 15.6, cumulative dose = 7.6 ± 4.4), with a subset of 20 patients assessed prospectively during treatment. Patient reported measures (EORTC-QLQ-CIPN20, R-ODS) were used to profile symptoms and disability. Neurological assessment was undertaken using the Total Neuropathy Score and nerve conduction studies. Sensory threshold and fine motor tasks were also undertaken. Comparisons of data between timepoints were calculated using paired-sample t tests or Wilcoxon matched-pairs signed-rank test. Comparisons between outcome measures were calculated with independent sample t tests or Mann-Whitney U tests for non-parametric data.

RESULTS: The majority of patients developed VIPN by mid-treatment (77.8%, 7.0 ± 3.3 weeks post baseline) with the prevalence remaining stable by end-of-treatment (75%, 8.1 ± 1.7 weeks post mid-treatment). By 3 months post-completion, 50% of patients still reported VIPN although there were significant improvements on neurological grading and functional assessment (P < 0.05). VIPN presented with sensorimotor involvement in upper and lower limbs and was associated with decreased sensory and motor nerve amplitudes, reduced fine-motor function and increased disability.

CONCLUSION: VIPN in adults presents as a sensorimotor, upper- and lower-limb neuropathy that significantly impacts disability and function. Neuropathy recovery occurs in a proportion of patients; however, VIPN symptoms may persist and continue to affect long-term quality of life.