Gastric lymphoma

Bilateral thoracic paravertebral masses, measuring up to 86 x 40 x 85 mm on the right, and 41 x 14 x 65 mm on the left.  
Gross circumferential thickening of the distal stomach and pylorus, resulting in a gastric tumor measuring 142 x 112 mm in transverse dimensions and 128 mm in craniocaudal diameter. The more proximal stomach is normal in appearance.  The adjacent fat appears clear.  No invasion of the adjacent organs.  Distally, this lesion is continuous with the duodenum, which appears otherwise normal.  The more distal bowel is unremarkable.    
The lumen of the common bile duct is normal in caliber, measuring up to 7 mm proximally.  However, there is diffuse circumferential soft tissue thickening about the duct, measuring up to 24 mm in transverse diameter, likely lymphadenopathy.  The intrahepatic bile ducts are unremarkable.  
Very numerous mildly enlarged mesenteric and retroperitoneal nodes, largest a 15 mm right retrocrural node and a 14 mm left para-aortic node.  Bulky soft tissue thickening anterior to the sacral promontory, extending from L4 to S2 levels.  This crosses the midline, and extends inferiorly on the left side where it encases the internal iliac artery.  The left-sided component measures 64 x 59 mm in transverse dimensions.  The lesion overall measures 141 mm in craniocaudal diameter.  
IMPRESSION:  
Unusually large gastric tumor on the basis of gross circumferential thickening of the distal stomach.  A gastric lymphoma is favored, particularly given extensive lymphadenopathy elsewhere.  Leiomyosarcoma or adenocarcinoma considered less likely.