[Predicting efficacy of neoadjuvant cheomotherapy on resectable stage IIIA non-small cell lung cancer by multi-gene expressions]

Abstract

Background & objective: Neoadjuvant chemotherapy for stage IIIA non-small cell lung cancer (NSCLC) remains controversial. The role of the expressions of P53, K-ras, HER2, vascular endothelial growth factor (VEGF), epidermal growth factor receptor (EGFR), CD44, and matrix metalloproteinase-9 (MMP-9) in predicting efficacy of neoadjuvant chemotherapy on stage IIIA NSCLC is still unclear although they have been found to be related to prognosis. This study was to determine the predictive effect of multi-gene expression on treatment outcome of neoadjuvant chemotherapy for resectable stage IIIA NSCLC.

Methods: Expressions of p53, K-ras, HER2, VEGF, EGFR, CD44, MMP-9 in the patients enrolled in the prospective randomized controlled trial were detected by immunohistochemistry. The treatment efficacies of combination (neoadjuvant chemotherapy combined with surgery) group (36 patients) and surgery alone group (32 patients) were compared.

Results: The high gene expression rate was 58.3% in combination group, and 40.6% in surgery alone group(P=0.145). In combination group, no significant difference of disease-free survival rate (P=0.903) and survival time (P=0.238) was found between patients with histopathologic regression and patients without histopathologic regression; high gene expression had no correlation with pathologic regression (P= 0.862); the mean disease-free survival time was significantly lower in high gene expression subgroup than in low gene expression subgroup [(14.1+/-9.8) months vs. (27.2+/-13.6) months, P=0.032]; the 2-year disease-free survival rate was 38.1% in high gene expression subgroup, and 46.7% in low gene expression subgroup (P=0.607).

Conclusions: Pathologic regression after neoadjuvant chemotherapy has no correlation with disease-free survival rate and survial time. The high gene expression maybe indicate high risk of postoperative metastasis; the necessity of postoperative chemotherapy needs further study.