Lapatinib combined with neoadjuvant paclitaxel-trastuzumab-based chemotherapy in patients with human epidermal growth factor receptor 2-positive breast cancer: A meta-analysis of randomized controlled trials

The purpose of the present study was to quantify the cumulative randomized evidence for the efficacy and safety of lapatinib combined with neoadjuvant therapy in human epidermal growth factor receptor (HER) 2-positive breast cancer. Three electronic databases, MEDLINE, Embase and Cochrane Central Register of Controlled Trials, and the abstracts of major international conferences between inception and 15 December 2013 were searched. Two evaluators independently extracted data. The end-points assessed consisted of the pathological complete response (pCR) rate, breast-conserving surgery (BCS) rate and the occurrence of adverse events. Four randomized controlled trials were assessed in the present study, involving a total of 779 participants. Compared with the patients who did not receive lapatinib, the pCR rate was higher in the hormone receptor (HR)-positive [risk ratio (RR), 1.39; 95% confidence interval (CI), 1.12–1.72; P=0.002) and HR-negative (RR, 1.38; 95% CI, 1.14–1.68; P=0.0009) patients that received lapatinib. No significant difference between the BCS rate of the two treatment arms was observed in two trials (n=382; RR, 1.14; 95% CI, 0.89–1.47; P=0.31). The primary adverse events, including diarrhea, dermatological toxicity, hepatic toxicity and neutropenia, were statistically more frequent in patients that received lapatinib (RR, 2.46; 95% CI, 1.97–3.07; P<0.00001). The present analysis revealed that the addition of lapatinib to neoadjuvant chemotherapy for HER2-positive breast cancer improves the probability of achieving a higher pCR rate, but the use of lapatinib is associated with a higher risk of adverse events.