Expression of COX-2 and HER-2/neu and estrogen and progesterone receptor in primary squamous cell carcinomas of the endometrium.

PURPOSE: Primary endometrial squamous cell carcinoma (ESCC) are rare but aggressive malignancies. To evaluate therapeutically relevant molecules, ESCC were investigated immunohistochemically. MATERIAL AND METHODS: Eight ESCC were stained with antibodies against estrogen and progesterone receptors, HER-2/neu, and COX-2 followed by semiquantitative evaluation of the staining results. RESULTS: Seven out of eight ESCC were negative for estrogen receptor as well as for HER-2/neu. Four tumors showed positivity for progesterone receptor. All ESCC displayed COX-2 overexpression. CONCLUSIONS: Primary ESCC are probably not under hormonal control of estrogens and lack HER-2/neu expression. Thus, anti-hormonal or antibody therapy with herceptine is not indicated. The use of COX-2 inhibitors might be a therapeutic alternative in ESCC that requires further investigation.