Angiogenesis as a prognostic marker in early head and neck cancer.

Experimental evidence suggests that tumor growth beyond the earliest stages is dependent on angiogenesis, or neovascularization, and that angiogenesis may also promote metastasis. Recent clinical studies demonstrate that angiogenesis is a prognostic marker in breast, lung, and prostate cancer. To investigate whether tumor angiogenesis also correlates with metastasis and survival in early head and neck carcinoma, we quantified the microvascularity of 106 primary carcinomas prior to treatment and correlated the counts with eventual outcome after 3 to 15 years of follow-up. Microvessels were stained immunocytochemically for von Willebrand factor and then counted by light microscopy. Microvessels were counted per 200x and 400x fields, and their density was graded from 1 to 4, in the area of most intense neovascularization. We found that neither microvessel counts nor density grades correlated with metastatic disease, local recurrence, or survival in early head and neck carcinoma. These results are in contradistinction to those recently reported for other tumor sites.