Low vascular density indicates poor response to radiotherapy in small glottic carcinomas.

Reportedly, the high density of vessels adjacent to various tumours is associated with increased tendency to metastasis and poor prognosis. In contrast, for other cancers a high vessel density is correlated with a good response to radiation therapy, and thus a good prognosis. In this study we measured the vessel density in 53 small glottic SCC (T1N0 and T2N0), treated with radiation (66-70 Gy). The blood vessels were visualised by an immunohistochemical staining method (ABC), using a primary antibody BE2 which reacts with blood group H antigen on endothelial cells. The intra- and interobserver reproducibility of the vessel counting was good (kappa = 0.78). We found a significant correlation between low vascular density and increased risk of recurrent disease (p = 0.0158). cox multivariate analysis showed that both vascular density and T-status were significant prognostic factors, p = 0.0036 and p = 0.0152 respectively.