Atypical Glandular Cells of Undetermined Significance in Cervical Smears After Conization

Abstract

To evaluate the cytologic features of atypical glandular cells of undetermined significance (AGUS) smears following conization through a comparison with adenocarcinoma in situ (AIS) smears. Fifty cervical smears, diagnosed as AGUS based on groups of crowded glandular cells that raised the possibility of AIS, from 38 patients who had conization and 24 AIS smears, histologically confirmed, from 17 patients were reviewed. Subsequent follow-up biopsies or hysterectomies in 38 patients were evaluated. Nuclear atypia was a more reliable feature than architectural structure in differentiating postcone effect from AIS on cytology. The predominant cytologic features of the postcone smears were crowded glandular cells with a high nuclear/cytoplasmic ratio and relatively small, hyperchromatic nuclei with rather finely granular and uniformly dispersed chromatin, less distinct nuclear membranes, less frequent mitosis and presence of endometrial-type stromal cells in the background. The architecture of the crowded cells in the postcone smears was sometimes similar to that of AIS. No AIS or high grade squamous intraepithelial lesion histology was encountered in follow-up biopsies or hysterectomy specimens. The cytologic features distinguishing AGUS from AIS may be helpful in identifying the postcone effect. Since it is important to avoid miscalling the postcone effect as AIS, it is recommended that one check for a previous history of a cone biopsy.