Persistent weekly paclitaxel-induced peripheral neuropathy in early breast cancer patients enrolled in a randomized trial of cryotherapy.

Chemotherapy-induced peripheral neuropathy (CIPN) is a serious side effect of weekly paclitaxel-based chemotherapy for breast cancer, that can persist for years. Cryotherapy therapy is effective for preventing early CIPN, but its protective effect on persistent CIPN is uncertain. This is a cross-sectional study conducted as an ancillary analysis of a randomized trial investigating the preventive effect of cryotherapy on CIPN in breast cancer patients receiving weekly paclitaxel-based chemotherapy (UMIN000034966). Eligible patients were evaluated for CIPN at more than a year after completion of the chemotherapy (persistent CIPN). CIPN was defined as a 6 or more points reduction from baseline in the Functional Assessment of Cancer Therapy-Neurotoxicity (FACT-NTX) score. The incidence of early and persistent CIPN was compared between cryotherapy and control groups. Thirty-eight patients were examined for both early and persistent CIPN. The median time from completion of the weekly paclitaxel-based chemotherapy to the questionnaire for persistent CIPN was 2.3 (1.3-3.1) years. In all 38 patients, persistent CIPN was demonstrated in 10 (26.3%), respectively. There was a numerical, however not significant, reduction in the incidence of persistent CIPN (15.8% vs 36.8%, P = .1) in the cryotherapy group compared with the control group, respectively. In multivariate logistic regression analysis, age ≥ 65 was a substantial risk factor for persistent CIPN (HR: 14.7, 95%CI: 1.7-130.7, P = .01). In breast cancer patients receiving adjuvant weekly paclitaxel-based chemotherapy, cryotherapy resulted in a numerical, however not significant, reduction in the incidence of persistent CIPN and age>=65 was a risk factor for persistent CIPN.