Aromatase expression in low-grade endometrial stromal sarcomas: an immunohistochemical study.
Aromatase expression has been described in stromal cells of endometriosis, adenomyosis and endometrial cancer. We analyzed aromatase expression in a series of 23 low-grade endometrial stromal sarcomas. Archival formalin-fixed and paraffin-embedded material was analyzed with immunohistochemistry. Aromatase expression was evaluated with a monoclonal and a polyclonal antibody using the peroxidase-antiperoxidase method. A score was calculated based on the percentage of positive tumor cells and the staining intensity. Aromatase was seen in 19 (83%) of 23 tumors with monoclonal antibody and 20 (87%) of 23 tumors with polyclonal antibody. Aromatase expression using the monoclonal antibody was scored as high in five (22%), moderate in nine (39%) and low in five (22%) tumors. Four (17%) low-grade endometrial stromal sarcomas did not stain for aromatase. Aromatase expression with the polyclonal antibody was scored as high in seven (31%), moderate in four (17%) and low in nine (39%) tumors. Three (13%) low-grade endometrial stromal sarcomas did not stain for aromatase. Little or no aromatase expression tended to correlate with stage I disease, while higher scores were more frequently associated with advanced disease. Our results demonstrate that most low-grade endometrial stromal sarcomas express aromatase. The staining pattern, however, is heterogeneous. The high percentage of aromatase positivity in low-grade endometrial stromal sarcomas may have implications in the management of these tumors and offer new treatment modalities such as hormonal therapy with aromatase inhibitors.
Reich
Olaf
O
Department of Obstetrics and Gynecology, University of Graz, Graz, Austria. olaf.reich@kfunigraz.ac.at
Regauer
Sigrid
S
D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use; D001141:Aromatase / Q000032:analysis* / Q000276:immunology; D047072:Aromatase Inhibitors / Q000627:therapeutic use; D016889:Endometrial Neoplasms / Q000188:drug therapy / Q000201:enzymology* / Q000473:pathology; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008875:Middle Aged; D009367:Neoplasm Staging; D018579:Patient Selection; D011379:Prognosis; D018203:Sarcoma, Endometrial Stromal / Q000188:drug therapy / Q000201:enzymology* / Q000473:pathology
D000911:Antibodies, Monoclonal; D018931:Antineoplastic Agents, Hormonal; D047072:Aromatase Inhibitors; D001141:Aromatase