BACKGROUND: The aim of this study was to assess the predictive value of tumor expression of nine genes on clinical outcome in patients with advanced NSCLC receiving platinum-gemcitabine chemotherapy. METHODS: Quantitative PCR or immunohistochemistry were used to analyze the expression of β-tubuline IIA (TUBB2A), β-tubuline III (TUBB3), BRCA1, ERCC1, Abraxas (ABRX) and RAP80 in mRNA isolated from paraffin-embedded tumor biopsies of 45 NSCLC patients treated as part of a larger observational trial. All patients received first-line platinum-gemcitabine chemotherapy for stage IIIB or IV NSCLC. RESULTS: Median progression-free survival (PFS) was 7 months, overall survival (OS) 12 months. A partial treatment response was found in 14 patients (33%). Patients with low ERCC1 or ABRX expression had a significantly better response to chemotherapy (R=-0.45, p<0.01 for ERCC1; R=-0.40, p=0.016 for ABRX). A significant correlation was found between the individual time for PFS and the expression of both ERCC1 (R=-0.36, p=0.015) and ABRX (R=-0.46, p=0.001). Patients with low ERCC1 expression had a longer OS as compared to patients with high ERCC1 expression (HR=0.26, log-rank p=0.02). CONCLUSIONS: The study confirms tumor expression of ERCC1 as a predictor for clinical outcome in patients with advanced NSCLC receiving platinum-based chemotherapy, and found ABRX expression to be similarly predictive of clinical outcome. Prospective validation is warranted and - if confirmed - non platinum-containing chemotherapy should be explored as the preferred treatment in patients with high ERCC1 or ABRX expression and no activating mutations of EGFR.
BACKGROUND: The aim of this study was to assess the predictive value of tumor expression of nine genes on clinical outcome in patients with advanced NSCLC receiving platinum-gemcitabine chemotherapy. METHODS: Quantitative PCR or immunohistochemistry were used to analyze the expression of β-tubuline IIA (TUBB2A), β-tubuline III (TUBB3), BRCA1, ERCC1, Abraxas (ABRX) and RAP80 in mRNA isolated from paraffin-embedded tumor biopsies of 45 NSCLCpatients treated as part of a larger observational trial. All patients received first-line platinum-gemcitabine chemotherapy for stage IIIB or IV NSCLC. RESULTS: Median progression-free survival (PFS) was 7 months, overall survival (OS) 12 months. A partial treatment response was found in 14 patients (33%). Patients with low ERCC1 or ABRX expression had a significantly better response to chemotherapy (R=-0.45, p<0.01 for ERCC1; R=-0.40, p=0.016 for ABRX). A significant correlation was found between the individual time for PFS and the expression of both ERCC1 (R=-0.36, p=0.015) and ABRX (R=-0.46, p=0.001). Patients with low ERCC1 expression had a longer OS as compared to patients with high ERCC1 expression (HR=0.26, log-rank p=0.02). CONCLUSIONS: The study confirms tumor expression of ERCC1 as a predictor for clinical outcome in patients with advanced NSCLC receiving platinum-based chemotherapy, and found ABRX expression to be similarly predictive of clinical outcome. Prospective validation is warranted and - if confirmed - non platinum-containing chemotherapy should be explored as the preferred treatment in patients with high ERCC1 or ABRX expression and no activating mutations of EGFR.