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.