Magnetic resonance imaging of endometrial cancer and clear cell cancer.

Objective: We attempt to clarify specific imaging findings useful for differential diagnosis between endometrioid cancer and clear cell cancer.
Methods: We examined magnetic resonance imaging features on 11 endometrioid cancer and 9 clear cell cancer patients. We compared them, focusing on the locularity, characteristic and growth pattern of solid components, and association with endometrial diseases.
Results: Endometrioid cancer had a predominantly multilocular appearance, but clear cell cancer showed almost equally multilocular and unilocular appearances. For the growth pattern, endometrioid cancer in 6 patients demonstrated a "centric pattern" and an "eccentric pattern" in 4, whereas clear cell cancer showed predominantly an eccentric pattern. An internal slit in the solid component was seen in 4 endometrioid cancer patients but not seen in any of the patients with clear cell cancer.
Conclusions: The magnetic resonance imaging appearance of the internal slit in solid components and the presence of endometrial disease are key factors in differentiating endometrioid cancer from clear cell cancer, although lesion locularity and growth pattern are not specific in both.