Islet cell tumors of the pancreas.

Pancreatic endocrine neoplasms are a heterogeneous group of tumors that produce active hormones and result in distinct clinical syndromes. For the most part, they are malignant and require sophisticated diagnostic and localization techniques in order to identify their presence. Delays in diagnosis are the rule rather than the exception. Improvements in the diagnosis of gastrinomas and insulinomas appear to result in an increase in resectability rates. The widespread availability of intraoperative ultrasonography, as well as improved knowledge of the location of these tumors, has also had an impact on improved cure rates. With heightened awareness of these syndromes, increasing numbers of patients can be identified and more effective treatments developed for the refractory and recurrent tumors.