Population-based study of the diagnosis and treatment of gastrointestinal stromal tumours

Background: The aim of this retrospective population-based study, which was conducted before the introduction of imatinib, was to evaluate the role of surgery in patients with gastrointestinal stromal tumours (GISTs) and clarify which subgroups might benefit from adjuvant treatment. Methods: Two hundred and fifty-nine patients with clinically detected GISTs were studied. Univariate and multivariate analyses were performed to identify predictors for recurrent disease and survival. Results: Thirty of 48 patients with high-risk GISTs and all of those with overtly malignant tumours developed recurrent tumour after complete (R0) resection. Thirty-four of 38 first recurrences occurred within 36 months of surgery. No recurrence was observed after 72 months. R0 resection, achieved in 48 (80 per cent) of 60 patients with high-risk tumours, was significantly associated with a decreased risk of death from tumour recurrence (P = 0.008). Conclusion: Completeness of surgical resection is an independent prognostic factor in patients with high-risk GISTs. A period of adjuvant treatment with imatinib is recommended in patients with high-risk or overtly malignant GISTs who have undergone R0 resection and have a tumour-free interval of less than 6 years.