Interactions between tumor cells and microvasculature are particularly critical. This computerized morphometric study was designed to analyze the distance between cancer cells and blood vessels and microvasculature organization in non-small cell lung carcinoma (NSCLC) comparing squamous cell carcinoma (SCC) and adenocarcinoma (ADC). Seventy nine nests of tumor cells, located less than or more than 3 mm from the invading edge, with a similar surface area, and their surrounding stroma were analyzed. After immunolabeling with an antihuman CD34 monoclonal antibody, computerized morphometric analyses of microvascular density (MVD), distribution of microvessels within stroma, and fractions of carcinomatous cells over various distances from microvessels were performed. This analysis showed a significantly higher MVD score in ADC than in SCC, particularly close to the invading edge (382+/-57 in ADC <3 mm; 242+/-28 in SCC <3 mm, p=0.015). Moreover, a significantly higher proportion of cancer cells was situated more than 75 microm from microvessels in SCC than in ADC, regardless of their site in relation to the invading edge (for example, 25+/-5% in ADC <3 mm; 52+/-3% in SCC <3 mm, p=0.001).