A 58 year old woman presented with postmenopausal uterine bleeding.
A TruTest® endometrial biopsy was performed using a Tao Brush® to sample the endometrium. Ample tissue fragments were received and were separated from the endometrial sample by filtration and submitted for histology. The remaining endometrial cytology material was processed by selective cellular enhancement technique and the slides were stained with Papanicolaou and acid hematoxylin methods.
The cytology brushing slides contained a highly cellular specimen composed of small and medium sized dyshesive cell groups. These cell groups were generally solid with a few small apparent glandular lumina (Fig. 1 and Fig. 2, Papanicolaou stain). Mitotic figures were present in some of these cell groups (Fig.2; Fig. 3, acid hematoxylin stain). Within the cell groups there was mild variation in nuclear size and shape with some nuclear overlapping. The individual nuclei were hyperchromatic and had slightly irregular nuclear contours. The finely granular nuclear chromatin was unevenly distributed with focal areas of clearing (Fig. 1, 2, and 3). Eosinophilic nucleoli were present (Fig. 2).
The histologic preparations revealed similar architectural and cytologic findings to those seen in the cytology slides. At low power (Fig. 4, hematoxylin and eosin stain) variably sized dyshesive groups of neoplastic cell were present. These groups were generally solid but small glandular lumina were occasionally present (Fig. 5, hematoxylin and eosin stain). Mitotic figures and eosinophilic nucleoli were more readily apparent in the histologic slides (Fig. 6, hematoxylin and eosin stain).
The differential diagnosis would include other high grade adenocarcinomas that occur in the endometrium such as serous carcinoma. Serous carcinomas often have a prominent papillary component; a feature not present in this case. Also, the marked nuclear pleomorphism and prominent eosinophilic macronucleoli associated with serous carcinoma were absent.
Endometrioid Adenocarcinoma, Grade 3
A subsequent hysterectomy revealed a grade 3 endometrioid adenocarcinoma arising in a background of complex atypical hyperplasia. There was no myometrial invasion.