The early onset of peripheral neuropathy might be a robust predictor for time to treatment failure in patients with metastatic breast cancer receiving chemotherapy containing paclitaxel

Background Paclitaxel plays a central role in chemotherapy for breast cancer. Peripheral neuropathy, a well-known toxicity with paclitaxel, may be of interest in predicting the efficacy of paclitaxel therapy for patients with metastatic breast cancer. We performed a retrospective analysis assessing whether the early occurrence of peripheral neuropathy (EPN) was a predictive marker for better efficacy in patients with metastatic breast cancer receiving chemotherapy containing paclitaxel. Patients and methods Between January 2000 and August 2008, we examined the records of 168 patients with metastatic breast cancer treated with paclitaxel in our hospital. EPN was defined as a symptom of Grade 2 or more during first three months of treatment. The overall response rate (ORR) and time to treatment failure (TTF) in each group were analyzed retrospectively. Results Of 168 patients with metastatic breast cancer who were treated with paclitaxel, EPN was documented in 101 patients (60.1%). The clinical benefit rate (CR, PR, and SD >= 6 months) was 72.3% in the EPN group and 49.3% in the non-EPN group (p = 0.002). The TTF of the EPN group (median 11.2 months, 95% CI: 9.5-12.9) was significantly longer than that of the non-EPN group (5.7 months, 95% CI: 4.6-6.8) (p<0.001). Multivariate analysis demonstrated that EPN (p<0.001), dose intensity of less than 70% (p<0.001), and the history of microtubule agents (p = 0.001) were the significant favorable prognostic factors for TTF. Conclusion The early onset of peripheral neuropathy might be a robust predictor for TTF in patients with metastatic breast cancer treated with paclitaxel.