Gastrointestinal stromal tumors: Clinical profile, pathogenesis, treatment strategies and prognosis

Gastrointestinal stromal tumors (GIST), although the most common mesenchymal neoplasms of the gastrointestinal (GI) tract, account for < 1% of all GI malignancies. Up to 94% of these tumors express the CD117 antigen. Most patients present in the fifth to seventh decade, the commonest symptom being that of an abdominal mass. Surgery is the main modality of therapy, but even after adequate resection the vast majority of GIST reoccur, and in approximately 50% the liver is the main site of the metastasis. Long-term, maybe even lifelong follow up of these patients after initial resection cannot be over-emphasized. Initial tumor size and mitotic rate are the most useful parameters to predict malignant potential. In view of high postoperative recurrence, adjuvant forms of therapy are being explored, and the tyrosine kinase inhibitor imatinib holds the most promise. (C) 2005 Blackwell Publishing Asia Pty Ltd.