Surgery for gastrinomas
The surgical approach to gastrinomas is more complex because these tumors are more frequently malignant and the majority occur outside the pancreas. Tumors in the pancreatic head can often be enucleated, reserving formal pancreaticoduodenectomy for more invasive tumors or those in close proximity to the pancreatic duct or superior mesenteric vessels. Tumors in the body or tail of the pancreas should be resected by distal pancreatectomy. Upper endoscopy with duodenal transillumination can aid in identification of lateral wall tumors. Duodenotomy should be performed in every operation to reduce the risk of missing a gastrinoma located in the duodenal wall (98% of gastrinomas will be found by doing this). Routine duodenotomy has also been shown to improve the long-term cure rate. Small submucosal lesions can be enucleated, but full-thickness resection of the duodenal wall may be necessary. These tumors have a propensity to metastasize to lymph nodes, and recent studies have shown not only that lymph node status has important prognostic value, but also that resection of lymph nodes improves survival and reduces the risk of persistent disease. Thus, it is recommended that routine lymph node resection be performed in all gastrinoma cases.