Tumor Angiogenesis as a Prognostic Marker in Operable Non–Small Cell Lung Cancer

Background. Recent evidence suggests that tumor angiogenesis is associated with patient outcome in a number of malignancies. However, little is known about the significance of tumor microvessel density as evaluated by an anti-CD34 antibody in patients with lung cancer. Methods. Tumor tissues were obtained from 101 patients with operable non–small cell lung cancers. Immunohistochemical detection of tumor-associated microvessels was performed using anti-CD34 antibodies directed against endothelial markers. Average counts of the three most vascular areas on a ×200 field were recorded. Results. Staining for CD34 was easy to interpret because of specific and minimal background staining. The Kaplan-Meier method showed a statistically significant difference between the microvessel count and overall survival. The microvessel count was identified as the only significant and independent prognostic marker. In both univariate and multivariate analyses, the microvessel count was significantly related to the development of hematogenous metastasis but failed to associate with the development of nodal metastasis. Conclusions. Tumor vascularity is an independent prognostic factor and important for the development of hematogenous metastasis.