Macrophages and microvessel density in tumors of the ovary.

Macrophages are members of the mononuclear phagocyte system and synthesize and release many angiogenesis stimulators and inhibitors. Previous studies have demonstrated heterogeneous macrophage populations in ovarian tumors. The aim of this study was to compare macrophage number between different types of ovarian tumors and between regions of high (HVD) and average (AVD) microvessel density (MVD). Macrophages were visualized using CD68 antibody. Previously determined regions of HVD and AVD were located on CD68 immunostained sections and image analysis software was used to count the number of positively stained cells per square millimeter. CD68-positive macrophage number did not differ between benign, mucinous, and serous ovarian tumors or between regions of HVD and AVD (ANOVA; P > 0.05). In both HVD and AVD regions of benign tumors, macrophage number positively correlated with MVD (Spearman rank correlation coefficient; P < 0.03). In contrast, a small but significant negative correlation between macrophage number and MVD was observed in HVD regions of serous tumors (Spearman rank correlation coefficient; P > 0.05). Macrophage infiltration does not appear to differ between ovarian tumor types; however, macrophages may have a positive influence on the vascularization of benign ovarian tumors. Copyright 1999 Academic Press.