This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: G.I.T, Subject name: Anatomy
Asymptomatic, solid 4cm tumor of distal pancreas. Treatment 
Select and explain. 
A. Observation, B. Distal pancreatectomy with splenectomy, C. Near total pancreatectomy with splenectomy, D. Distal pancreatectomy alone
D: Distal pancreatectomy alone
Answer: D: Distal pancreatectomy alone 
Explanation: Resectional Surgery for pancreatic Body and Tail Tumors Most body and tail cancers have already metastasized to distant sits or extended locally to involve nodes, nerves or major vessels by the time of diagnosis Splenic vein involvement or occlusion is not a sign of nonresectability Involvement of the splenic and SMV confluence generally precludes resection Resection involves a distal pancreatectomy either with or without concomitant splenectomy Splenectomy is usually performed with distal pancreatectomy in patients suspected of having carcinoma to obtain better margins, to remove the lymph nodes at the tip of the pancreas and hilum of the spleen, and to avoid tedious dissection of the splenic aery and vein Ref: Sabiston 20th edition Pgno :1547