Identification of "papillary-like" clusters on endometrial cytologic preparations

The presence of papillary cell clusters is taken as a serious indication in the diagnosis of well-differentiated endometrial adenocarcinoma in Japan. However, papillary-like clusters have been observed in both normal and benign samples. Therefore, overdiagnosis may occur in the observation of cytopreparations. The present study attempts to prepare a histological sample from an Auto Cyto Fix (ACF) sample prepared by the automatic fixation apparatus (ACF1000) using a membrane filter method after cytological observation and to examine its usefulness. In an ACF sample, a papillary-like cluster was observed and the coverslip was then removed, the circumference of the membrane filter was cut off, and the target cell cluster was smeared, embedded, and sliced. In the cases in which a papillary-like cluster was observed, even if differential diagnosis of the derivation was difficult due to a resemblance between the respective morphological findings, it was easily made by histological observation of an ACF sample.