In contrast, none of the other rare NF1-associated tumors demonstrated ALT (Additional file 1: Table S3), including gastrointestinal stromal tumors (GIST), pheochromocytomas, glomus tumors, juvenile xanthogranulomas, and duodenal neuroendocrine tumors. This evidence concerns the gene NF1 and duodenal neuroendocrine tumor, well differentiated, low or intermediate grade.