COX-2 expression in uterine carcinosarcoma

Objective. To assess cyclooxygenase-2 (COX-2) expression in the carcinomatous and sarcomatous elements of uterine carcinosarcoma. Design. Retrospective study. Setting. Medical center. Sample. Twenty-seven consecutive uterine specimens with carcinosarcoma. Methods. COX-2 expression assessment by immunohistochemistry was performed on deparaffinized sections of paraffin-embedded tissue blocks. Analysis of all stained tissue sections was done by means of light microscopy counting 10 high power fields with a minimum of 1,000 cells per slide. Analysis of the stained tissue sections was done by pathologists blinded to the clinical data and the follow-up course of the malignancy. Main outcome measures. Staining of more than 10% of the cells was considered positive. Staining intensity was graded on a 03 scale. A scoring index was calculated by multiplying the intensity grade by the percentage of stained cells and considered low when it was ≤1 and high when it was >1. COX-2 expression was associated with prognostic factors and survival. Results. COX-2 immunohistochemical staining was positive in 74% of the carcinomatous component of carcinosarcoma and a high staining score was observed in 48.2%. Staining parameters were significantly lower in the sarcomatous component. No significant association between COX-2 expression with stage, grade, depth of myometrial invasion, lymphvascular involvement or with survival was observed. Conclusions. COX-2 is expressed in a high percentage of uterine carcinosarcoma, but does not seem to be associated with prognostic factors or survival.