Five-year follow up of patients with gastrointestinal stromal tumor: recurrence-free survival by risk group.

Aim: Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the gastrointestinal tract. There is limited published data on GIST from the Indian subcontinent. This 5-year retrospective analysis of 49 patients treated for GIST reports clinical and pathological features and survival outcome by risk stratification. Methods: We reviewed 49 cases of GIST from January 2004 to December 2008. Imatinib was administered after surgery in patients with either high-risk, residual or metastatic disease and at onset of recurrence or metastatic disease in patients with intermediate risk. Results: The mean age was 50years (range, 1780years). Patients with localized tumor were classified as low (n=2), intermediate (n=4) and high risk (n=32), based on the primary tumor and mitotic index. At a median follow up of 21months, 2-year and 3-year recurrence or progression-free survival rates were 61 and 39%, respectively, for all patients. The median recurrence-free survival rate in the intermediate-risk and high-risk groups were 7 and 49months, respectively. The median progression-free survival in the residual (n=4) and metastatic disease group (n=7) was 10 and 29months, respectively. Conclusion: This study demonstrates the role of imatinib in adjuvant and therapeutic settings. Responses have been durable and most patients tolerate the drug well at clinically effective doses. In view of high recurrence rates in the intermediate-risk group in our study, it would be better to keep these patients on strict follow up to detect recurrence at the earliest opportunity.