Poorly differentiated adenocarcinoma with extensive rhabdoid differentiation: clinicopathological features of two cases arising in the gastrointestinal tract.

This paper describes the pathological features of two cases of composite extra-renal rhabdoid tumor; that is, poorly differentiated carcinoma with extensive rhabdoid differentiation, arising in the small intestine of a 64-year-old man and in the pancreas of a 77-year-old woman. In both cases the tumor behaved aggressively and the patients died from disseminated malignancy within 3 months of original presentation and diagnosis. To the best of our knowledge these are the first examples of such tumors in the small intestine and pancreas.