Bcl-2 is an independent prognostic factor and adds to a biological model for predicting outcome in operable non-small cell lung cancer

INTRODUCTION: The underlying biology of a tumour may hold the key to predicting the outcome for an individual patient as well as identifying potential therapeutic targets. Using epidermal growth factor receptor (EGFR) and matrix metalloproteinase (MMP)-9 immunoexpression combined with microvessel counts we have developed a prognostic model for operable non-small cell lung cancer (NSCLC) which predicts outcome independent of stage (Thorax, 56 (2001) 561-566). The aim of this study was to evaluate the impact of bcl-2 expression upon survival in this model. METHODS: This was a retrospective analysis of 167 patients with resected stage I-IIIa NSCLC and >60 days post-operative survival. Minimum follow-up was 2 years. Immunohistochemistry was performed on paraffin-embedded tissue sections for bcl-2, EGFR, MMP-9 and the microvessel marker CD34 to evaluate the relationships between, and impact on survival of these biological markers. RESULTS: Tumour cell MMP-9 (P=0.002), microvessel count > median (P=0.01), bcl-2 (P=0.02) and stage (P=0.02) were independent prognostic factors. Bcl-2 expression was associated with an improved survival in all sub-groups of our prognostic model. CONCLUSION: bcl-2, EGFR and MMP-9 expression and angiogenesis provide prognostic information independent of TNM stage. Prognostic models offer the potential of tailoring the therapeutic management for an individual patient.