A 50 year old woman presented with irregular menstrual 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.
specimen containing variable sized irregularly shaped cell groups (Fig. 1 Papanicaloau stain, Fig. 2 Acid Hematoxylin stain). Occasional cystic structures were present (Fig. 3 Papanicaloau stain). In some of the cell groups, there was mild variation in nuclear size and shape and slight irregularities in the nuclear contours. Small nucleoli were present (Fig. 4 Papanicaloau stain, Fig. 5 Acid Hematoxylin stain).
In the histologic preparation, variable sized, closely spaced endometrial glands were present. The gland outlines were irregular with focal branching and infoldings (Fig. 6 H&E Stain). Even in the more cellular areas, the glands were still separated by a small amount of stroma. On high power examination, nuclear stratification with focal loss of polarity was evident. The individual nuclei were rounded rather than ovoid and showed variation in size. There was coarsening of the chromatin pattern and nucleoli were present.
Complex Atypical Hyperplasia.
While the cytologic features of atypical hyperplasia and well-differentiated (grade 1) endometrioid adenocarcinoma overlap; the architectural patterns are different. Grade 1 adenocarcinomas have a more confluent growth pattern with formation of cribriform glandular structures. In these structures, there is no intervening stroma between the glands. A papillary growth can also be present.