Gastrinoma can metastasize to a variety of locations, including the lymph nodes and liver. The presence of gastrinoma in peripancreatic lymph nodes is not evidence of incurability [11, 12, 24-26], if the nodes can be completely resected at the time of surgery for the primary tumor. Some have advocated an aggressive approach to liver metastases, including debulking procedures. The tumor related mortality in patients with metastatic gastrinoma can be as high as 79% [11].

The search for better prognostic markers continues. In a study of 27 gastrinomas, 12 (44%) had chromosome 1q loss of heterozygosity (LOH). Such LOH was associated with aggressive tumor growth and development of liver metastases [27]. Other than the initial presence of distant metastases, or the development of disease progression on long-term follow-up, it has been difficult to establish whether a particular gastrinoma is malignant. A recent study examined 21 consecutive patients with neuroendocrine pancreatic tumors. Of the different biological markers examined, increased levels of topoisomerase II alpha had a 88% sensitivity, and 100% specificity for predicting malignancy [28].