@entity7457 is useful for primary site determination in duodenal XXXX .

@entity1 @entity706 @entity5 @entity3003 @entity2 @entity1311 @entity420 @entity136 @entity3 @entity2220 @entity7457
We report here on a case of duodenal @entity3 from primary @entity2220 . A 69-year old @entity1 was diagnosed with primary @entity2220 . Four courses of combined chemotherapy with @entity3003 and @entity1311 associated with irradiation of 60 Gy shrunk the @entity2 . However, soon after,the para-aortic lymph node became swollen. Esophagogastroduodenoscopy revealed three duodenal @entity5 . Differential diagnosis between @entity706 and metastatic @entity5 was endoscopically difficult. The histology of biopsied specimens was poorly differentiated @entity420 . Immunohistochemical analysis revealed a positive reaction for @entity7457 ( @entity7457 ). Thus, we concluded that these were metastatic duodenal @entity5 from @entity2220 . Two courses of @entity136 led to a complete remission in this duodenal @entity3 and para-aortic lymph node swelling with only scarring remaining in computed tomography. He is now on the continuous generalized chemotherapy. In conclusion, duodenal @entity3 from primary @entity2220 is rare and hard to diagnose. In such an instance, @entity7457 immunostaining is crucial to obtain the correct diagnosis.
