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What is In exocrine pancreatic, cancer, the commonest tumor marker to be elevated in and explain in detail?
.Investigations for exocrine pancreatic tumors includes * Liver function tests: Serum bilirubin, direct component (conjugated) is increased (van den Bergh's test). Serum albumin is decreased with altered A : G ratio. Prothrombin time is widened. Serum alkaline phosphatase is increased * U/S abdomen to see gall bladder, liver, growth, CBD size (normal diameter is < 10 mm), lymph node status, poal vein, ascites. * Barium meal shows widened duodenal "C" loop-- pad sign. Reverse 3 sign is seen in carcinoma--periampullary region. * Spiral CT scan (ideal) shows poal vein infiltration, retroperitoneal lymph nodes, size of the tumour. * ERCP with pancreatic juice cytology or brush biopsy is useful. MRCP to see biliary tree. * CA 19-9 (carbohydrate antigen) is a useful tumour marker. * Coeliac and superior mesenteric angiogram can be done to reveal tumour circulation and invasion. * Gastroduodenoscopy reveals ampullary tumour and biopsy can also be taken. * Endosonography is useful to see the invasion and size, to stage and to do EUS guided FNAC. * Urine for bile salts (Hay's test), bile pigments (Fouchet's test), urobilinogen. ref:SRB&;S manual of surgery,ed 5,pg no 634