Obstructive Jaundice Secondary to Primary Duodenal Lymphoma with CMV Duodenitis Causing Upper GI Bleed in Retro-Positive Patient: A Case Report.

Gastrointestinal (GI) tract is the most common site of extranodal lymphoma. Primary GI lymphoma constitutes a small amount of all lymphomas. Primary duodenal lymphoma presenting initially with obstructive jaundice is very rare. Primary B-cell lymphoma of the duodenum was shown to be the cause of biliary obstruction in a retropositive male, which was proved by endoscopic biopsy. Histopathology also showed cytomegalovirus inclusion bodies with duodenitis.

Ewing's sarcoma of the lesser sac masquerading as a pancreatic tumor.

Extraosseous Ewing's sarcoma/primitive neuroectodermal tumor (ES/PNET) is an uncommon, aggressive, and malignant tumor with a poor patient outcome. Its occurrence in the lesser sac is a rare event and to the best of our knowledge, has not been previously described. The present case was clinically and radiologically misdiagnosed as a pancreatic tumor/gastrointestinal stromal tumor. Histopathology revealed a tumor with "small round cells" that were positive for CD99, confirming the diagnosis of ES/PNET. This report highlights the importance of considering Ewing's sarcoma in the differential diagnosis of intraabdominal, extraintestinal masses.