Endometrial Lesions, Unusual Tumors, and Extrauterine Cancer
Fig. 10.7 An endometrial cell ball. (LBC, SurePath Papanicolaou x HP).
Note the central core of collapsing stroma with pyknotic nuclei, and the
peripheral, draping epithelium.
Fig. 10.9 Normal-appearing endometrial cells. (LBC, ThinPrep
Papanicolaou x HP). Nuclear details can only be discerned in some cells. Note
small amount of cytoplasm, and granular-appearing chromatin.
Fig. 10.8 An endometrial cell ball. (LBC, SurePath Papanicolaou x HP).
Fig. 10.10 Normal-appearing endometrial cells. (LBC, ThinPrep
The peripheral epithelium covering a central stromal core shows small
Papanicolaou x HP). IMote similar sized nuclei and cytoplasmic vacuolation.
prominent in days 5 to 8 of the menstrual cycle. Endometrial
epithelial cells are often closely packed and the nuclear
details may be difficult to discern (Fig. 10.9). They have
small, round to oval, darkly staining nuclei in which nuclear
molding may be noted.
eral nuclear condensation, and apoptotic bodies (single cell
necrosis) can be present. The cytoplasm of endometrial cells is
usually scant although occasionally small vacuoles can be seen
(Fig. 10.10). The cell borders are not well delineated and are often
overlapping. Endometrial cell balls are not infrequently infil-
trated by neutrophils (Fig. 10.11). The cytoplasm of the endome-
trial cells may appear to have engulfed the neutrophils, a finding
referred to as emperipolesis. When neutrophils are found within
vacuolated glandular cells other entities need to be considered
and excluded, including microglandular hyperplasia of the
cervix and endocervical polyps.
In liquid-based preparations, endometrial cells groups
appear tighter and single cells may be more prominent.43
Although some endometrial cellular fragments present as rel-
atively flat strips many cell groups have a three-dimensional
appearance which extends above the plane of focus. The
nuclear detail is often better preserved and the nuclei may
appear as bean-shaped with sharper chromatin detail and
nucleoli evident (Fig. 10.12). Nuclear pleomorphism may
be accentuated with liquid-based fixation (Fig. 10.13). The
cytoplasm may appear to be more abundant and vacuoles are
common. The bloody background of conventional smears is
diminished although stromal cells and histiocytes can still be