Phase III two by two factorial comparison of doxorubicin and cyclophosphamide followed by a taxan vs. a taxan alone, and paclitaxel vs. docetaxel in operable node positive breast cancer – results of the first interim analysis of NSASBC02 trial.

Abstract

Abstract Abstract #4103 Background: Evidence suggests that anthracycline-containing regimens can be excluded in some patients(pts) with operable breast cancer. It is also suggested that docetaxel (D) is more effective than paclitaxel (P) in metastatic breast cancer (BC) pts.
 Methods: Eligibility included axillary lymph node positive BC age less than 70 years old. Pts were randomized to receive either AC(doxorubicin 60 mg/m2 and cyclophosphamide 600 mg/m2) every(q) 3 weeks(wks) x 4 followed by P 175 mg/m2 q3 wks x 4 (ACP), same AC followed by D 75 mg/m2 q3 wks x 4(ACD), P 175 mg/m2 q3 wks x 8 (PTX) or D 75 mg/m2 q3 wks x 8(DTX). Comparison included taxane (ACP+PTX vs. ACD+DTX) and with AC or without AC (ACP+ACD vs. PTX+DTX). The primary endpoint was disease free survival (DFS) and the secondary endpoints included overall survival, adverse events(AE) and quality of life (QOL). The trial was powered to prove the non-inferiority of regimens without AC to those with AC(threshold hazard ratio 1.321) in terms of DFS.
 Results: A total of 1,060 eligible pts were accrued from 84 centers between Dec. 2000 and Mar.2006. 270 DFS events and 106 deaths after a median follow-up of 46.5 months were observed. The hazard ratio (HR) of DFS between ACD+DTX and ACP+PTX was 0.81(95% Confidence Interval (CI); 0.64-1.03) (p=0.08). The HR of DFS between PTX+DTX and ACP+ACD was 1.26 (95% CI; 0.99-1.60) ( p=0.67) in all eligible pts but was 1.85 (95% CI; 1.11-3.07)(p=0.017) in pts with HER2 overexpressing BC and 1.11(95% CI; 0.85-1.46)( p=0.44) in pts with HER2 non-overexpressing BC. AEs of grade 3 or 4 were observed in the lowest incidence in PTX arm and edema was observed in 11% of pts in DTX arm(p=0.01), neutropenic fever was more frequent in D cotaining arms(Table1). Conclusions: DFS was better in the arms containing D than in the arnms with P. AC improved DFS in the subset of pts with HER2 overexpressing BC but not in non-selected population. Higher incidence of severe AEs was observed in the arms containing D than in arms with P.
 
 Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4103.