Serum pancreastatin: the next predictive neuroendocrine tumor marker.

BACKGROUND AND OBJECTIVES: Pancreastatin is a derived peptide of chromogranin A (CgA). Pancreastatin has the potential to be a diagnostic and predictive tumor marker in detecting NETs. METHODS: Radioimmunoassay tests of pancreastatin and CgA were performed on 103 patient specimens collected at Mount Sinai Medical Center between 1/2010 and 7/2012. Patient demographics, diagnostic tests, surgical procedures, pathologic findings, adjuvant treatments, and survival were retrospectively reviewed. Statistical analysis utilized SPSS v20 software. RESULTS: Mean pancreastatin levels were significantly higher in the 92 NETs patients than in the 11 non-NETs patients (227.261 vs. 59.727, P < 0.05). Twenty-seven of the 92 patients with elevated pancreastatin levels (mean = 240.67), had normal CgA levels (mean = 4.65). Pancreastatin had sensitivity and specificity of 64% (59/92), and 100% (11/11). CgA had lower sensitivity and specificity of 43% (40/92), and 64% (7/11). In all 27 instances the pancreastatin concentration was found to be sole indicator of NET disease. When controlling for the level of CgA for the entire sample, a statistically significant difference was not found in the mean pancreastatin levels between both patient groups (P = 0.139, R = 0.484). CONCLUSION: Pancreastatin has greater sensitivity and specificity in diagnosing NETs than CgA. Further investigation of pancreastatin's diagnostic and predictive value is warranted.