title: Neuroendocrine differentiation in adrenocortical carcinoma. New immunohistochemical findings supported by electron microscopy.
abstract: Ten adrenocortical carcinomas including two tumors with clinically detectable corticosteroid production, were immunohistochemically analyzed for their intermediate filament proteins, and for neuroendocrine markers. Keratins were present in 6 of 10, vimentin in all 10, and the 68 kilodalton kD neurofilament subunit protein in 6/10 tumors. Keratins numbers 8 and 18 were most prevalent, whereas only traces of keratins 19 and 7 were found. Eight tumors were positive for synaptophysin at least focally, and 3 showed extensive positivity in more than 30% of tumor cells. The tumors showed approximately similar levels of neuron-specific enolase (NSE) expression as judged by immunohistochemistry. Chromogranin was not detected, and there was no immunoreactivity for 3 neuropeptides (calcitonin, gastrin, somatostatin). In normal adrenal cortex, neuron-specific enolase, synaptophysin and neurofilaments were restricted to the nerves seen between the cortical cells. Electron microscopy revealed clusters of dense-core granules in 4 of 5 tumors, consistent with neuroendocrine granules. These results indicate that adrenocortical carcinomas may show signs of neuroendocrine differentiation and share some features with the adrenal medullary tumors.
authors.affiliation: Department of Pathology and Cell Biology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, Pennsylvania.
authors.forename: M
authors.initials: M
authors.lastname: Miettinen
mesh_terms: D000293:Adolescent; D000306:Adrenal Cortex Neoplasms / Q000737:chemistry* / Q000473:pathology*; D000328:Adult; D000368:Aged; D015415:Biomarkers; D002277:Carcinoma / Q000737:chemistry* / Q000473:pathology*; D002454:Cell Differentiation; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D009490:Neurosecretory Systems / Q000166:cytology
chemical_list: D015415:Biomarkers