Gastrointestinal stromal tumours: outcomes of surgical management and analysis of prognostic variables.

Background: We sought to review the clinical presentation and outcomes of surgical management of gastrointestinal stromal tumours (GISTs).

Methods: We reviewed clinical and pathological records of 41 patients (23 men and 18 women) with GISTs. We performed survival analyses using the Kaplan- Meier method and evaluated long-term survival and the independent prognostic factors that affect survival using univariate analyses. We used the Cox proportional hazards regression model to estimate the simultaneous effect on overall survival.

Results: The stomach was the most common tissue of origin (n = 20, 48.8%). The mean tumour diameter was 8.3 cm. We detected advanced-stage tumours in 22 (53.7%) patients. We performed complete resection in 31 (75.6%) patients. Mitotic count was greater than 5/50 high-power field [HPF] in 22 (53.6%) patients. Immunohistochemical staining for CD117 was positive in 40 (97.6%) patients. Five patients (12.2%) died in the early postoperative period. The mean follow-up period was 38.7 months. The median length of survival was 53 months and the 5-year survival rate was 49.4%. Univariate analyses revealed significantly enhanced survival for the following variables: patient age less than 60 years (p = 0.011), male sex (p = 0.048), tumour diameter less than 5 cm (p = 0.029), low-risk tumour according to Fletcher classification (p = 0.022), complete resection (p < 0.001), and lack of local recurrence (p < 0.001) and/or metastasis (p < 0.001). Our Cox proportional hazards model revealed that complete tumour resection was the only factor to increase survival.

Conclusion: Overall survival is significantly affected by positive margins. A complete surgical resection with negative margins is the best method for definitive treatment of GISTs.