Remarkable effects of imatinib in a family with young onset gastrointestinal stromal tumors and cutaneous hyperpigmentation associated with a germline KIT -Trp557Arg mutation: case report and literature overview

AbstractGastrointestinal stromal tumors (GISTs) occur mostly sporadically. GISTs associated with a familial syndrome are very rare and are mostly wild type forKIT and platelet-derived growth factor alpha (PDGFRA). To date 35 kindreds and 8 individuals have been described with GISTs associated with germlineKIT mutations. This is the third family described with a germline p.Trp557Arg mutation in exon 11 of theKIT gene. The effect of imatinib in patients harboring a germlineKIT mutation has been rarely described. Moreover, in some studies imatinib treatment was withheld considering the lack of evidence for efficacy of this treatment in GIST patients harboring a germlineKIT mutation. This paper describes a 52-year old patient with a de novo germline p.Trp557Arg mutation with multiple GISTs throughout the gastrointestinal tract and cutaneous hyperpigmentation. Imatinib treatment showed long-term regression of the GISTs and evident pathological response was seen after resection. Remarkably, the hyperpigmentation of the skin also diminished during imatinib treatment. Genetic screening of the family revealed the same mutation in two daughters, both with similar cutaneous hyperpigmentation. One daughter, aged 23, was diagnosed with multiple small intestine GISTs, which were resected. She was treated with adjuvant imatinib which prompted rapid regression of the cutaneous hyperpigmentation. Imatinib treatment in GIST patients harboring a germlineKIT mutation shows favorable and long-ter...
Source: Familial Cancer - Category: Cancer & Oncology Source Type: research