The Role of Chromogranin A Assay in the Diagnosis of Pheochromocytomas

Background: Pheochromocytomas (Pheo) are rare neuroendocrine tumors with a suggestive clinical picture, characterized by hypersecretion of catecholamines and other neuroendocrine biomarkers. Methods: The purpose of the study was to analyze the diagnostic features of Pheo and investigate the role played by different neuroendocrine and hormonal markers in diagnosing Pheo.The retrospective study involved a group of 69 patients diagnosed and treated with Pheo, who had both urinary and plasma catecholamines and neuroendocrine markers measured pre- and postoperatively. Results: After comparing pre- and postoperative hormonal parameters and neuroendocrine biomarker changes, numerous statistically significant findings were found. The analysis of the relationships between chromogranin A (CgA) levels, plasma and urine metanephrines, and normetanephrine and Pheo tumor size was included in the study. Additionally, we evaluated Cg A's diagnostic efficacy in comparison to plasma metanephrines, normetanephrine, and neuron-specific enolase (NSE) for Pheo. Conclusions: We obtained statistically significant data on pre- and postoperative differences for plasma and urinary catecholamines, CgA and NSE. Pheo tumor size is interdependent with serum levels of Cg A, plasma and urinary metanephrines, and normetanephrine. The best diagnostic power for Pheo was plasma normetanephrine, followed by plasma metanephrines and CgA.