Chromogranin A in the Laboratory Diagnosis of Pheochromocytoma and Paraganglioma

Abstract

This work discusses the clinical performance of chromogranin A (CGA), a commonly measured marker in neuroendocrine neoplasms, for the diagnosis of pheochromocytoma/ paraganglioma (PPGL). Plasma CGA (cut-off value 150 µg/L) was determined by an immunoradiometric assay. Free metanephrine (cut-off value 100 ng/L) and normetanephrine (cut-off value 170 ng/L) were determined by radioimmunoassay. Blood samples were collected from PPGL patients preoperatively, one week, six months, one year and two years after adrenal gland surgery. The control patients not diagnosed with PPGL suffered from adrenal problems or from MEN2 and thyroid carcinoma. The clinical sensitivity in the PPGL group of patients (n = 71) based on CGA is 90% and is below the clinical sensitivity determined by metanephrines (97%). The clinical specificity based on all plasma CGA values after surgery (n = 98) is 99% and is the same for metanephrines assays. The clinical specificity of CGA in the control group (n = 85) was 92% or 99% using metanephrines tests. We can conclude that plasma CGA can serve as an appropriate complement to metanephrines assays in laboratory diagnosis of PPGL patients. CGA is elevated in PPGLs, as well as in other neuroendocrine or non-neuroendocrine neoplasia and under clinical conditions increasing adrenergic activity.

Recurrent Pheochromocytoma in an Elderly Patient

“…A tumor size of greater than 5 cm and extra-adrenal tumor location possess greater risk of metastatic transformation. In contrast, our case shows the location of the tumor to be adrenal– in which case, metastatic transformation risks include looking at dopamine secretion, other secretory molecules and tumor cell necrosis [ 17 , 18 , 19 , 20 , 21 ].…”

Specific and Non-Specific Biomarkers in Neuroendocrine Gastroenteropancreatic Tumors

“…All granins—including Chromogranin B and C, as well as secretogranin II, III and IV—are precursors of biologically active substances [11]; for example, CgA is a precursor of pancreastatin, catestatin, and vasostatins I and II. While all granins could be secreted by neuroendocrine tumors, CgA is the only one routinely used in clinical practice: The assay has a high sensitivity [9] and good specificity [10], and CgA is secreted by most NETs, including malignant ones [9,12,13,14]. A significant, positive relationship (r = 0.9858, p ˂ 0.0001) has been reported between serum and plasma CgA, suggesting that either measurement provides an adequate estimate of circulating CgA [15].…”

Circulating miRNA Increases the Diagnostic Accuracy of Chromogranin A in Metastatic Pancreatic Neuroendocrine Tumors

“…An elevated level of circulating CgA has been associated with almost all tumor types of the neuroendocrine system [1,5], but its sensitivity varies between 47-100% depending on tumor type (100%, in gastrinomas,~89% in pheochromocytomas, and~69% in nonfunctioning pNETs) [1,[6][7][8].…”