My father (65 yrs) is having feeling of fullness, diarrhoea and body pain from last few months. After endoscopy the result is 2 diminutive polyps (0.2cm) in the duodenum. Biopsy result is well differentiated neuroendocrine tumor grade 1. Confirmation test result is; Synaptophysin: positive Chromogranin: weakly positive Ki-67 index: 1%. Is it a malignant growth? If so what is the management. Please help with your opinion.