Associations between self-reported diet during treatment and chemotherapy-induced peripheral neuropathy in a cooperative group trial (S0221)

Background: The pathophysiology of chemotherapy-induced peripheral neuropathy (CIPN) is not well understood. Currently, dose reduction is the only recommendation for alleviating symptoms, often leading to premature treatment cessation. The primary aim of this analysis was to determine the association between components of diet during taxane treatment for breast cancer and change in CIPN symptoms over treatment. Methods: Women with stage II or III invasive breast cancer were enrolled into an ancillary study to the North American Breast Cancer Intergroup phase III trial (S0221) led by the Southwest Oncology Group (SWOG). Questionnaires including a food frequency questionnaire and the Functional Assessment of Cancer Treatment Gynecologic Oncology Group - Neurotoxicity were administered to assess diet and neuropathic conditions at baseline and during chemotherapy. Ordinal regression was used to estimate odds ratios (ORs) for associations between various food groups and change in neuropathy score (< 10%, 10-30%, > 30%) (n = 900). Results: The odds of worse neuropathy decreased by 21% for each increase in tertile of grain consumption (OR = 0.79, 95% CI 0.66-0.94, p = 0.009). We also observed a nominal 19% increase with higher consumption of citrus fruits (OR = 1.19, 95% CI 1.01-1.40, p = 0.05). Conclusions: Distinguishing between those who experienced a moderate and a severe change in neuropathy, we found that citrus fruit and grain consumption may play a role in the severity of symptoms. Since there are no existing dietary recommendations for the management of CIPN, further research is needed to investigate whether there may be certain foods that could worsen or alleviate neuropathy symptoms associated with treatment for breast cancer. Trial registration: ClinicalTrials.gov, NCT03413761. Registered retrospectively on 29 January 2018.