Estrogen Sulphotransferase Expression in Endometrial Stromal Sarcomas: an Immunohistochemical Study

Background: Levels and activity of the enzyme estrogen sulphotransferase (EST) have been reported to play an important role in the regulation of in-situ estrogen levels in human breast, prostate and endometrial cancer. To better understand the growth progression in endometrial stromal sarcomas (ESS), estrogen dependent tumors, we analyzed EST expression in a series of 29 ESS. Methods: Archival formalin-fixed and paraffin-embedded material was analyzed immunohistochemically with a monoclonal antibody to EST using the peroxidase-antiperoxidase method. A score was calculated based on the percentage of positive tumo…