Collagen Type III Formation and Distribution in the Uterus: Effects of Hormones and Neoplasm Development

Abstract

The amount and location of interstitial collagen in the endometrial stroma and the uterine wall as well as the effects of hormonal stimulation and neoplastic transformation were studied by light and electron microscopy and immunohistochemical methods using specific antibodies to aminoterminal propeptide type III procollagen (PIIIP). The results showed collagen deposition in atrophic mucosae and in the proliferative endometrium with a decrease in the secretory endometrium. In cystic glandular hyperplasia and adenomatous hyperplasia, PIIIP deposits were abundant. In well-differentiated endometrial adenocarcinoma, dense collagen type III aggregates were found in subepithelial positions, disintegrating with advancing malignancy and decreasing in hormonal-treated morphologically well-differentiated neoplasms. The even distribution of PIIIP around muscle cells and bundles in leiomyomas was disturbed and partly absent in leiomyosarcomas, and surrounded epithelial islets in mixed mesodermal tumors.