<h4>Objective</h4>The aim of this study was to assess the immunohistochemical expression of second-generation neuroendocrine markers such as insulin gene enhancer protein 1, insulinoma-associated protein 1, and secretagogin in pheochromocytoma and their prognostic value.<h4>Methods</h4>The study included 30 operated pheochromocytoma patients. This evidence concerns the gene INSM1 and hereditary pheochromocytoma-paraganglioma.