Cytological features of atypical polypoid adenomyoma

Abstract

Objectives : We studied the cytological features of atypical polypoid adenomyoma (APA).
Study Design : We analyzed six cases of endometrial smears histologically identifying APA and compared them to normal endometrium (n=17), endometrial hyperplasia (n=8), and endometrioid adenocarcinoma of the uterine corpus, Grade 1 (G1, n=8).
Results : Cytological APA features were as follows : (1) Smooth muscle-like spindle cell cluster. Sensitivity [se] : 66.7% Specificity [sp] : 100% compared to others. (2) Squamous metaplastic (morular) change. se : 33.3%. (3) Branching or papillary cluster. se : 33.3%. (4) Branching or net-like vascular stroma. se : 83.3%. (5) Coexistence with normal endometrial glands. se : 100%. (6) Clear background. se : 83.3%. sp : 100% compared to G1.
Conclusion : A distinct cytological APA feature is the smooth muscle-like spindle cell cluster. It is important to observe other features, such as background, to appropriately interpret endometrial cytology.