Background: Type 1 neurofibromatosis (NF1) is a genetic disease characterized by neoplastic and not neoplastic disorders, involving tissues of neuroectodermal or mesenchymal origin. The mainly involved districts are skin, central nervous system, and eye, and there is a wide range of severity of clinical presentations.
Data sources: Abdominal manifestations of NF1 comprehend five categories of tumors: neurogenic with neurofibromas, malignant peripheral nerve sheath tumors and ganglioneuromas, neuroendocrine with pheochromocytomas and carcinoids, non-neurogenic gastrointestinal stromal tumors, i.e., GISTs, and embryonal tumors and miscellaneous.
Conclusions: Early diagnosis of these abdominal manifestations is very important given the risk of malignancy, organic complications such as in the case of pheochromocytomas or hemorrhagic-obstructive complications such as in the case of the tumors of the gastrointestinal tract (GISTs and neurofibromas). The importance of an annual clinical evaluation on the part of a multidisciplinary pool of clinicians in highly specialized centers allows early detection of complications and of neoplastic transformation.