Rectovaginal septum endometriosis: an immunohistochemical analysis of 62 cases.

Deep infiltrating endometriosis of rectovaginal septum is a particular form of endometriosis located under the peritoneal surface. This kind of lesions are very active and strongly associated with pelvic pain symptoms. A study on 62 cases of rectovaginal septum endometriosis by means of immunohistochemistry was conducted in order to evaluate the oestrogen and progesterone receptor levels in these cases and to correlate them to the level of vascularization (CD34 expression) and the amount of nerve fibres (S100 expression). Data showed great heterogeneity in the expression of all the parameters analyzed. Nevertheless, by using Spearman correlation test to assess relationship among oestrogen and progesterone receptors, S100 and CD34 staining, a significant direct correlation was found between all the parameters analyzed. These observations sustain the hypothesis that oestrogen and progesterone play an important role in the genesis of endometriotic glands, in the vascularization and in the proliferation of nerves.