Radiation changes include marked cellular and nuclear enlargement with maintained nuclear to cytoplasmic ratios (cytomegaly); irregular nuclear contours; open, smudged chromatin; and visible nucleoli. Cytoplasmic and nuclear vacuolation and multinucleation also may be observed. A history of radiation to the area is essential.
In atrophy, the entire cellular population appears blue (with Papanicolaou stain) due to lack of squamous cell maturation resulting in an absence of pink, flat superficial squamous cells. The main cellular component is parabasal squamous cells with oval nuclei, present in clusters or as isolated cells. Aggregates of naked parabasal cell nuclei, inflammation, and degenerated cells with large smudged nuclei known as “blue blobs” also may be present.
According to the 2001 Bethesda System, the presence of exfoliated endometrial cells in women aged 40 or greater should be reported. Because an individual woman’s risk factors for endometrial carcinoma, clinical symptoms, menstrual history, hormone therapy history, and menopausal status are often not provided to the laboratory, the 2001 Bethesda system created a category called “Other” for reporting the presence of exfoliated endometrial cells in all women 40 or older.
The depicted cellular cluster is glandular. Squamous cells are larger, and usually lay flat, not in three dimensional clusters; however, isolated or clusters of high grade squamous cells may show some overlapping features with endometrial cells. Additional cytologic findings and clinical data, such as menstruation history (LMP), would be helpful.
Compared to exfoliated endometrial cells, endocervical cells usually are larger in size, with polarized nuclei and lower nuclear to cytoplasmic ratios, and often occur as flat sheets rather than spherical clusters. The presence of central crowded/collapsed stromal cells in the cell ball is a helpful finding indicating endometrial origin. In addition, there is no cytologic atypia in the endometrial cells in the photomicrograph.
