Pathological analysis of the resected submucosal 1.8 cm tumour of the Meckel diverticulum confirmed a well differentiated neuro-endocrine tumour (grade I), whereas immunohistochemistry was positive for ACTH, chromogranin A and synaptophysin; Ki-67 score was < 1 % (Fig. 4). The gene discussed is MKI67; the disease is neoplasm.