HER-2, EGFR, COX-2 expression status correlated to microvessel density and survival in resected non-small cell lung cancer

The incidence of lung cancer is increasing throughout the world and is the most common cause of cancer-related death. Early detection followed by surgery has a reasonable, curative potential, but 30-50% of patients experience relapses. The immunohistochemical expressions of HER-2, EGFR and COX-2 were investigated in 53 resected non-small cell lung carcinomas and correlated to microvessel density and clinical data. HER-2, EGFR and COX-2 overexpressions were demonstrated in 15%, 30% and 40% of the tumours, respectively. In adenocarcinomas, HER-2 and COX-2 overexpression were more common, whereas in squamous cell carcinomas, EGFR overexpression was more common. COX-2 expression correlated with HER-2 expression (p = 0.002), and demonstrated a trend towards a correlation with microvessel density (p = 0.10). None of the markers alone had any impact on survival. However, HER-2+/EGFR- tumours proved to have a poor prognosis. In conclusion, adjuvant treatment with HER-2 antagonists might be a future treatment option in resected non-small cell lung cancer patients, especially when HER-2 is overexpressed without a concomitant overexpression of EGFR.