Diagnostic value of squamous cell change associated with endometrial carcinoma: A cytopathologic approach

Background To determine the frequency of squamous cell change associated with endometrial carcinoma, to evaluate the relationship between squamous cell change and clinicopathological features, and to assess cytological findings for squamous cells with and without nuclear atypia in endometrial smears. Methods In 103 cases of endometrioid adenocarcinoma of the endometrium having both histological and cytological specimens, the frequencies and relationships between the presence and absence of squamous cell changes were evaluated, as were the clinicopathological features of such changes. In endometrial smears, squamous cells with and without nuclear atypia were clinicopathologically assessed. Results Squamous cell changes were found in 58.3% of cases that had both histological and cytological preparations. There were no significant differences between the group with squamous cell changes and the group without in any of the clinicopathological features. In the cytological smears, 70.0% of the 60 cases that showed squamous cell changes in both preparations did not have nuclear atypia of squamous cells, while 30.0% of those cases had atypia. The group of cases with squamous cells without atypia tended to be better differentiated than the group with atypia. Vessels were permeated significantly more often in the group with atypia than in the group without. Conclusions Our data suggest the importance of observing squamous cells in endometrial cytology, especially concerning findings on nuclei with vs without atypia, when endometrial carcinoma is suspected. Diagn. Cytopathol. 2016;44:187-194.