Criteria for differential diagnosis of complex hyperplasia or beyond in endometrial cytology

To establish qualitative criteria for diagnosing complex hyperplasia, complex atypical hyperplasia and well-differentiated adenocarcinoma in endometrial cytology.

The frequency of appearance of papillary and arborescent cell clusters and the morphology of type A stromal bundles in arborescent cell clusters were examined in 59 samples of complex hyperplasia, 23 of complex atypical hyperplasia, 77 of well-differentiated adenocarcinoma and 40 of normal endometrium.

Papillary cell clusters were observed in all samples of hyperplasia and adenocarcinoma. The rate of observation of arborescent cell clusters increased proportionately to the progress from complex hyperplasia to complex atypical hyperplasia to well-differentiated adenocarcinoma. No arborescent cell clusters were found in normal endometrium. Primary branching and the number of layers of type A stromal bundles also increased with the progress toward complex hyperplasia and well-differentiated adenocarcinoma. Secondary and further branching was observed in large numbers in cases of adenocarcinoma.

For detection of complex hyperplasia or lesions beyond it in endometrial cytology, it is important to observe the presence of papillary clusters. For differentiation of the various lesions, it is important to observe the presence of arborescent clusters as well as type A stromata inside the clusters.