Utility of chromogranin A, pancreatic polypeptide, glucagon and gastrin in the diagnosis and follow-up of pancreatic neuroendocrine tumours in multiple endocrine neoplasia type 1 patients

ObjectivePancreatic neuroendocrine tumours (PNETs) are the major source of disease-specific mortality in multiple endocrine neoplasia type 1 (MEN1) patients. Chromogranin A (CgA), pancreatic polypeptide (PP), glucagon and gastrin have some diagnostic value in sporadic PNETs, but there is very little evidence for their efficacy in diagnosing PNETs in MEN1 patients. DesignWe performed a retrospective chart review of the existing MEN1 database in our institution. PatientsOne hundred and thirteen patients were eligible for diagnostic value analysis of tumour markers. Patients were excluded if measurement of tumour markers was missing, either 3 months prior to PNET diagnosis (PNET patients) or prior to abdominal imaging (non-PNET patients). MeasurementsClinicopathologic characteristics and of tumour marker measurements were analysed. ResultsOf 293 confirmed MEN1 cases, 55 PNETs and 58 non-PNETs met inclusion criteria. The area under the curve (AUC) for CgA, PP, glucagon and gastrin in MEN1 cases was 595%, 641%, 770% and 759%, respectively. The AUC for the combination of CgA, PP and gastrin was 596%. PP, but not CgA, glucagon or gastrin was significantly associated with both age and PNET functional status (P = 00485 and 00188, respectively). No markers were significantly associated with sex, PNET size, tumour number, tumour location, American Joint Committee on Cancer (AJCC) stage, presence of lymph node metastasis, lymphovascular invasion or overall survival. CgA values were not significantly lower following PNET resection than pre-operatively (P = 0554). ConclusionsThe value of blood markers for diagnosing PNETs in MEN1 patients is relatively low, even when used in combination.