A ten-year retrospective analysis of gastroenteropancreatic neuroendocrine tumors (GEP-NETs) in Malaysia

Gastroenteropancreatic neuroendocrine tumours (GEP- nETs) are rare neoplasms with a complex spectrum of presentation. The study cohort (n=64) included the diagnoses of carcinoid, (n=26, 41%), insulinoma, (n=25, 39%), undetermined (n=10, 16%), VIPoma, glucagonoma and multiple endocrine neoplasia (MEn-1) (n= 3). Almost half of the patients (n=31) had distant metastasis at diagnosis, the commonest being carcinoid tumours. Presenting symptoms were due to either hormonal expressions or mass effects. diagnoses in all patients were made based on positive immunohistochemical staining for chromogranin and synaptophysin. Less than half (n=30) had either serum chromogranin A, urinary 5-hydroxyindole acetic acid (5-hIAA), serum insulin or C-peptide levels performed. Commonest diagnostic imaging modalities were computed tomography (CT) scan (94%) and abdominal ultrasound (15%). Curative or palliative surgery was performed in 58 patients. Systemic therapy included long acting somatostatin analogues (n=14), chemotherapy (n=7) and interferon-α2b (n=1). nine patients died, all of who had metastatic disease at diagnosis. All patients with insulinoma (n=25) were assessed by endocrinologists whilst carcinoid tumours were mainly managed by surgeons (n=16/26). Involvements of oncologists and gastroenterologists were minimal. This study showed that patients with GEP-nETs in Malaysia commonly presented late in the disease with presence of distant metastases. Less than half had adequate hormonal and biochemical examinations performed for diagnostic as well as prognostic purposes, and only a third received systemic therapy. Lack of institutionalbased database, clinical expertise and multi-disciplinary involvement contributed to the inadequate surveillance and management of the disease.