Aims:
The objectives of this study were (a) to report our experience regarding the association between neurofibromatosis type 1 (NF1) and gastrointestinal stromal tumors (GISTs); (b) to provide a systematic review of the literature in this field; and (c) to compare the features of NF1-associated GISTs with those reported in sporadic GISTs.
Methods:
We reported two cases of NF1-associated GISTs. Moreover we reviewed 23 case reports/series including 252 GISTs detected in 126 NF1 patients; the data obtained from different studies were analyzed and compared to those of the sporadic GISTs undergone surgical treatment at our centre.
Results:
NF1 patients presenting with GISTs had a homogeneous M/F ratio with a mean age of 52.8 years. NF1-associated GISTs were often reported as multiple tumors, mainly incidental, localized at the jejunum, with a mean diameter of 3.8 cm, a mean mitotic count of 3.0/50 HPF, and KIT/PDGFR α wild type. We reported a statistical difference comparing the age and the symptoms at presentation, the tumors' diameters and localizations, and the risk criteria of the NF1-associated GISTs comparing to those documented in sporadic GISTs.
Conclusions:
NF1-associated GISTs seem to have a distinct phenotype, specifically younger age, distal localization, small diameter, and absence of KIT/PDGRF α mutations.