The Role of Macrophages in Angiogenesis. Comparison Between HIV + and HIV - Populations with Anal Dysplasia and Anal Cancer

Background: While macrophages (CD68+) have been associated with angiogenesis in some inflammatory and neoplastic processes by increasing the release of vascular endothelial growth factor (VEGF), their role in anal intraepithelial neoplasia (AIN) and anal squamous cell carcinoma has not been established. This study records macrophage infiltration in anal pre-invasive and invasive lesions in HIV+ and HIV- populations, and determines their relationship with angiogenesis. Materials and Methods: Sixty patients (31 HIV+) with AIN and anal SCC were studied. Paraffin sections were stained for CD68, VEGF and von Willebrand factor. The density of CD68 cells, the expression of VEGF and angiogenesis were quantified, and compared amongst groups and between HIV+ and HIV- populations. Results: All three parameters increased linearly as the lesions became more dysplastic, in HIV+ and HIV- groups. The CD68 count was statistically lower in HIV+ (p