Published online Dec 26, 2019. doi: 10.12998/wjcc.v7.i24.4398
Peer-review started: September 27, 2019
First decision: November 19, 2019
Revised: November 22, 2019
Accepted: November 26, 2019
Published online: December 26, 2019
Processing time: 89 Days and 4.2 Hours
Gastrointestinal stromal tumors (GISTs) associated with neurofibromatosis are uncommon compared to their gastrointestinal counterparts. Patients with neurofibromatosis type 1 (NF-1) have an increased risk of developing gastrointestinal tumors, including rare types such as GIST.
A 60-year-old male Chinese patient was diagnosed with NF-1 10 years ago and presented with upper abdominal discomfort and black stools. Endoscopic ultrasonography and an enhanced abdominal computed tomography scan revealed a mass located 4 cm from the muscular layer of the descending duodenum. A 59-year-old Chinese woman who was diagnosed with NF-1 25 years ago presented with sudden unconsciousness and black stools. Multiple masses in the duodenum were noted by echogastroscopy and an enhanced abdominal computed tomography scan. Both patients presented with cutaneous neurofibromas. The histologic examination of tumors from both patients revealed spindle cells and low mitotic activity. Immunohistochemically, the tumor cells showed strong positivity for KIT (CD117), DOG-1, CD34, and Dehydrogenase Complex Subunit B, and negativity for SMA, desmin, S-100, and β-catenin. None of the six tumors from two patients had KIT exon 9, 11, 13, or 17 or platelet-derived growth factor receptor α exon 12 or 18 mutation, which is a typical finding for sporadic GISTs. None of the six tumors from the two patients had a BRAFV600E mutation. The patients were alive and well during the follow-up period (range: 0.6-5 yr).
There have been only a few previous reports of GISTs associated with NF-1. Although GISTs associated with NF-1 have morphologic and immunohistochemical similarities with GISTs, the pathogenesis, incidence, genetic background, and prognosis are not completely known. A medical history of NF-1 in a patient who has gastrointestinal bleeding or anemia and an intra-abdominal mass with nonspecific computed tomography features may help in diagnosing GIST by virtue of the well-known association of these two entities. Molecular genetic studies of cases indicated that GISTs in NF-1 patients have a different pathogenesis than sporadic GISTs.
Core tip: Gastrointestinal stromal tumors (GISTs) associated with neurofibromatosis are uncommon compared to their gastrointestinal counterparts. Here we reported two cases of KIT and platelet-derived growth factor receptor α wild-type GISTs with neurofibromatosis type 1. Although GISTs with neurofibromatosis type 1 have morphologic and immunohistochemical similarities with common GISTs, the pathogenesis, incidence, genetic background, and prognosis are not completely known. A medical history of neurofibromatosis type 1 in a patient who has gastrointestinal bleeding or anemia and an intra-abdominal mass with nonspecific computed tomography features may help in diagnosing GIST by virtue of the well-known association of these two entities.