Evaluation of chromogranin A determined by three different procedures in patients with benign diseases, neuroendocrine tumors and other malignancies.

Unlabelled: CgA is a tumor marker in NET's (neuroendocrine tumors) but different ranges of sensitivity and specificity according to the commercial assay kits used have been reported. Our aim was to compare three commercial available assay kits that use three different methodologies (IRMA, RIA and ELISA) to determine CgA, in a clinical setting: 52 healthy people, 98 patients with benign diseases, 94 patients with non-NET´s malignancies, 20 SCLC and in 79 patients with NET's.

Results: Using a cut-off with a 100% specificity in healthy people (6 nmol/L, 60 ng/ml, and 90 ng/ml, for RIA, ELISA and IRMA, respectively), abnormal serum concentrations of CgA were found in a high proportion of patients with renal failure (76.