Fig. 2

Vessel density is increased in early stage LSCC. T-stage was determined in LSCC patients (n = 97). The number of patients without (N0) or with lymph node metastasis (N+) was determined for each T-stage. High T-stage correlated with positive node status (Kruskal-Wallis test; p = 0.001) (a). The absolute number of vessels per microscopic visual field was determined by immunohistochemistry and correlated with tumor T-stage (b) and N-stage (c). A high vessel count correlated with low T-stage (Kruskal-Wallis test; p = 0.004) and the absence of lymph node metastasis (Mann-Whitney-U test; p = 0.028). Data are depicted as box-plots indicating mean and absolute numbers of CD31 positive vessels and error bars