1997 Volume 36 Issue 2 Pages 190-194
We report a case of epithelioid leiomyosarcoma of the ileum initially showing malignant cells of unknown origin in the ascites. The patient was a 63-year-old woman. Cytological features in the ascites included a scattered distributioti or minimally cohesive cluster of large atypical cells with an inflammatory background. The unclei of the tumor cells were oval and nucleoli were prominent. The cytoplasm was densely stained light green. Occasionally, the cytoplasm was pale and vacuolated. Macroscopically, the tumor was 18×8×7 cm in size growing through the entire wall of the ileum with ulcer formation. This tumor had ariser from the muscularis propria. Invasions to the mesentery, the omentum and the urinary bladder were observed. The cutsurface was solid and whitish with central necrosis. Histological features of the tumor were a compact proliferation of round or spindle-shaped cells with epithelioid arrangements. The individual tumor cells were surrounded by well -developed reticulin fibers.
Immunohistochemical analysis revealed positive staining for EMA, cytokeratin, vimentin and smooth muscle actin, while staining for desmin and myoglobin was negative. Ultrastructural findings included abundand myofilaments in the cytoplasm. From these findings, we diagnosed this tumor as epithelioid leiomyosarcoma of the ileum. However, in this case, it was very difficult to make an accurate cytological diagnosis. It is thought to be important to consider the possibility of this tumor when epithelioid cells are recognized in ascites fluid.
