Mixed endocrine pancreatic tumors producing several peptide hormones.

Twenty-four endocrine pancreatic tumors were examined immunohistochemically for insulin, glucagon, gastrin and ACTH. In seven of these tumors, more than one peptide-hormone-containing cell type was observed. These seven tumors were also examined with conventional staining methods for the presence of A1, A2, and B cells. The results showed that these staining methods do not always distinguish between the different hormone-producing cell types of endocrine pancreatic tumors. In spite of the fact that several types of hormone-secreting cells were found in the tumors, the case histories described symptoms characteristic of hypersecretion of only one of the hormones. The hormone of the predominating cell type could not always explain the clinical symptoms. Our results indicate the endocrine pancreatic tumors often are multihormonal. Therefore, it would seem advisable to screen serum from all insuloma patients for a variety of peptide hormones.