Neoadjuvant imatinib in a locally advanced gastrointestinal stromal tumour (GIST) of the rectum: a rare case of two GISTs within a family without a familial GIST syndrome.

Gastrointestinal stromal tumours are rare tumours of the gastrointestinal tract. We describe the case of a 57-year-old man with a locally advanced gastrointestinal stromal tumour of the rectum. We started Gleevec. The pathological examination documented a complete pathological response. An already described mutation in KIT exon 11 was observed in the gastrointestinal stromal tumour of the rectum. At the same time as the treatment of our patient, his brother received a neoadjuvant therapy for a locally advanced rectal adenocarcinoma. During the surgical procedure, a gastric lesion was excised and the pathological examination showed a low-grade gastrointestinal stromal tumour. We analysed DNA extracted from the tumoral mass and normal tissue of both patients. No mutations, either in KIT or in PDGFRA, were detected in the subserosal stomach gastrointestinal stromal tumour. After 18 months, both patients are free from recurrence. Our clinical case suggests that preoperative imatinib therapy may enable radical surgery in patients with an inoperable disease.