Nonhyperfunctioning Endocrine Tumors

Endocrine tumors of the pancreas are easily distinguishable from other pancreatic neoplasms when specific clinical syndromes related to hypersecretion of gastroenteropancreatic peptides are present (KITAJIMA et al. 1998). Imaging can identify the single or multiple lesions that produce these clinical findings. Unfortunately, this is not always possible because of the small dimensions and the frequent extrapancreatic location of the lesions. Sometimes endocrine tumors can produce peptides but not in sufficient amounts to result in a specific clinical syndrome. These lesions are called nonhyperfunctioning endocrine tumors (NHFET). From a pathological point of view, these tumors are indistinguishable from hyperfunctioning ones. Their size is usually larger because of the delay in the diagnosis (KITAJIMA et al. 1998). For the same reason, signs of malignancy, such as locoregional infiltration and/or distant metastases, are more common at presentation.