The Effects of Endocervical Canal Topography, Tubal Metaplasia, and High Canal Sampling on the Cytologic Presentation of Nonneoplastic Endocervical Cells

Abstract

Use of new endocervical cytologic sampling devices has correlated with increased numbers of cases showing endocervical "atypia." To ascertain the potential causes, a cytologic and histologic correlative study of the normal endocervical canal was undertaken. Hysterectomy specimens from 25 patients with no history of cervical disease were used. The anterior and posterior endocervical canals were divided into three equal sections. Each of the sections of the anterior canal were sampled cytologically, with the corresponding posterior canal processed for histology. Endocervical gland number, depth, and cellular crowding were most pronounced in the middle third of the canal. Tubal metaplasia (present in 100% of cases) was most prominent in the upper third. The most cellular cytologic samples were obtained from the middle third. "Atypical" endocervical groups were most commonly identified in the upper third. The normal topography of the endocervical canal, with sampling of the upper regions by newly utilized devices, may account for the increase in samples showing cytologic patterns that mimic endocervical neoplasia.

Significance of benign endometrial cells in papanicolaou tests from women aged ≥ 40 years

“…With the improved sampling of the endocervical canal conferred by these devices, sampling of cells of the lower uterine segment has also occurred more frequently. 52 Such lower uterine segment cells and tuboendometrioid metaplastic cells may be interpreted either as endometrial cells or considered in the differential diagnosis of atypical endocervical cells. 53 An additional potential source of increased prevalence of endometrial cells in Pap tests is the increase in cervical surgical procedures brought about by the introduction of new techniques, such as the loop electrosurgical excision procedure (LEEP) that can manage cervical intraepithelial neoplasias safely and effectively on an outpatient basis.…”

Adenocarcinoma in situ with a small cell (endometrioid) pattern in cervical smears

“…The principal differential diagnosis is with small glandular cells, which may be derived either from the upper endocervix, sometimes with tubal or tuboendometrial metaplasia, 8,9 or from the endometrium. 10,11 Smears with such benign cells are more commonly encountered than those with AIS, and it is crucial that cytologists recognize this distinction in attempting to increase sensitivity for AIS without a large increase in falsely positive smears. The value of the criteria previously developed 2 and education in the use of these criteria has been demonstrated in this study.…”

Papanicolaou Smear Sensitivity for Adenocarcinoma In Situ of the Cervix:A Study of 34 Cases

“…Such groups have been illustrated in earlier cytologic studies of AIS (reference 12, Fig 5; reference 14, Fig 2, B; reference 17, Fig 10-23). However, they are sometimes difficult to differentiate from small endocervical cells directly scraped from the upper portion of the cervical canal 45 or from the lower uterine segment of the endometrium. 29 Clues to the neoplastic nature of these cells include extreme nuclear crowding, uniform nuclear hyperchromasia with slight chromatin coarseness, and lack of a spectrum that includes more obviously benign endocervical or lower segment endometrial cells.…”