Chinese multicenter randomized trial of customized chemotherapy based on BRCA1 (breast cancer susceptibility gene 1)-RAP80 (receptor-associated protein 80) mRNA expression in advanced non-small cell lung cancer (NSCLC) patients

Abstract

Objective: BRCA1 (breast cancer susceptibility gene 1) and RAP80 (receptor-associated protein 80) play key roles in predicting chemosensitivity of platinum and taxanes. A randomized trial was carried out to compare non-selected cisplatin-based chemotherapy with therapy customized according to BRCA1 and RAP80 expression. Methods: Advanced stage NSCLC patients whose tumor specimen was sufficient for molecular analysis were randomized (1∶3) to the control or experimental arm. Patients in the control arm received docetaxel/cisplatin; in the experimental arm, patients with low RAP80 expression received gemcitabine/cisplatin (Arm 1), those with intermediate/high RAP80 expression and low/intermediate BRCA1expression received docetaxel/cisplatin (Arm 2), and those with intermediate/high RAP80 expression and high BRCA1 expression received docetaxel alone (Arm 3). The primary end point was progression-free survival (PFS). Results: 226 patients were screened and 124 were randomized in this trial. ORR in the four subgroups was 22.6%, 48.4%, 30.3% and 19.2%, respectively (P=0.08); PFS was 4.74, 5.59, 3.78 and 2.73 months, respectively (P=0.55); and OS was 10.82, 14.44, 10.86 and 10.86 months, respectively (P=0.84). The common adverse effects included neutropenia, nausea, anemia and fatigue. Conclusions: No statistically significant difference of ORR, PFS or OS is observed in the experimental arms compared with the control arm. Patients with low RAP80 mRNA levels have a trend of better survival and higher response rate to gemcitabine/cisplatin chemotherapy.