# Chemotherapy-induced neuropathy (CIN) persists chronically for most individuals with breast cancer who develop the condition: A survey study

## TL;DR

Most breast cancer patients who develop chemotherapy-induced neuropathy from taxane treatment experience long-term symptoms and neuromotor issues.

## Contribution

This study provides new insights into the chronicity and predictors of CIN in breast cancer patients.

## Key findings

- 84.9% of surveyed individuals reported persistent CIN sensory symptoms.
- High A1C levels were predictive of CIN chronicity.
- 85% of those with chronic CIN showed neuromotor dysfunction.

## Abstract

A majority of individuals treated with taxane agents for breast cancer (BC) develop chemotherapy-induced neuropathy (CIN) yet questions remain regarding long-term prognosis of this neurologic complication. We sought to characterize CIN chronicity in terms of persistence rate, predictors, and neuromotor dysfunction.

We surveyed individuals with BC who developed CIN during taxane exposure at least 3 months prior. We calculated the proportion of survey respondents with/without chronic CIN symptoms and performed a sensitivity analysis, computing the largest and smallest possible rate of CIN chronicity given the number of non-respondents. Additionally, we analyzed predictors of chronicity (e.g., age, hgA1c level) and characterized the proportion of individuals with chronic sensory symptoms who also demonstrated neuromotor dysfunction.

We surveyed two hundred and fifty-eight individuals (99.2% female). Mean(SD) age = 60.5(11.1); time since last taxane exposure = 3.25(2.38) years; and A1C = 5.64(0.607). Persistent CIN sensory symptoms were reported by 84.9% [95% CI 79.5%, 90.3%]. Accounting for both the non-response sensitivity analysis and statistical uncertainty, we calculate bounds for the CIN persistence rate to be no lower than 50.5% and no higher than 93.6%. Variables predictive of CIN chronicity included high A1C (p = 0.037). Variables not predictive included total chemotherapy dose (p = 0.8); race (white vs non-white, p = 0.4); age (p = 0.09); time since last taxane exposure < 6 years (p = 0.051). Among those with chronic CIN, 85% demonstrated quantifiable neuromotor dysfunction.

CIN symptoms persist chronically for most individuals (~ 85%) with breast cancer who develop the condition during taxane treatment. Novel interventions are needed to alleviate sensory symptoms and associated neuromotor dysfunction.