Background and aim
Desmoid tumors are mainly treated by surgical excision and radiotherapy, but the failure to achieve complete response has given rise to the need for investigating the role of possible target therapy. The aim of this study was to evaluate the immunohistochemical detection of cyclooxygenase-2 (COX-2) and estrogen receptor-β (ERβ) in desmoid tumors and to assess their correlation with available clinicopathologic variables.
Materials and methods
A total of 17 desmoid tumor cases (11 abdominal, five extra-abdominal, and one intra-abdominal) were examined for immunohistochemical detection of COX-2 and ERβ using monoclonal antibodies. Toluidine blue staining was performed to confirm or exclude that COX-2 immunostained cells coincide with mast cells in co-localized sections. Correlation of results with available clinicopathologic variables was done and a value less than 0.05 was considered significant.
Results
COX-2 was expressed in tumor cells in 92% of examined desmoid cases (16/17). Toluidine blue staining has shown that COX-2 immunostained cells do not coincide with the few metachromatically stained mast cells in co-localized sections. ERβ was expressed in 67.1% of tumor cells in desmoid cases (11/17); eight cases displayed high ERβ expression and three cases displayed low ERβ expression. No significant correlation was detected between ERβ or COX-2 immunohistochemical expression and patient’s age, sex, tumor size, site, margins status, and recurrence history (>0.05).
Conclusion
This study confirmed the immunohistochemical expression of COX-2 and ERβ in tumor cells of the majority of studied desmoid cases. These results introduce COX-2 and ERβ as potential therapeutic targets in desmoid tumors. Further studies with a large sample size and follow-up are recommended to validate the current results.