Report of three new cases of squamous carcinoma of the endometrium with emphasis in the HPV status.

Primary squamous cell carcinoma of the endometrium is exceedingly rare. Only 31 cases that fulfill Fluhmann's criteria have been reported in the literature. We report three cases of primary squamous cell carcinoma of the endometrium. In two of the three cases, estrogen receptor (ER) and progesterone receptor (PR) status were analyzed. Only one case contained ER/PR. Additionally, in situ hybridization was performed to determine the presence of human papillomavirus (HPV) in these cases. HPV was not detected in these three cases of primary squamous cell carcinoma of the endometrium.