Adjuvant Imatinib treatment after R0 resection for patients with high‐risk gastrointestinal stromal tumors: A median follow‐up of 44 months

Abstract

BACKGROUND: The optimal duration of Imatinib adjuvant treatment for patients with high-risk gastrointestinal stromal tumors (GISTs) is uncertain. PATIENTS AND METHODS: A total of 90 patients with high-risk GISTs after curative resection were recruited into this non-randomized case-control study, including 35 having Imatinib adjuvant therapy and 55 having follow-up alone. The recurrence-free survival (RFS) was compared. RESULTS: After a median follow-up of 44.0 months, a significantly reduced recurrence rate was observed in the treatment group than the control group (17.1% vs. 78.2%, P = 0.000). One-year, 2-year, and 3-year RFS rates were 100% vs. 70.9%, 88.0% vs. 37.8%, and 88.0% vs. 27.5%, respectively; with a significant advantage for Imatinib adjuvant therapy versus the surgery only (P = 0.000, HR 0.122, 95% CI 0.041-0.363). Continuation Imatinib treatment further improved RFS by comparison with the interruption treatment (both 2-year and 3-year RFS were 95.8% vs. 63.6%, P = 0.011, HR 0.103, 95% CI 0.012-0.883). There were no serious adverse events in the adjuvant therapy group. CONCLUSIONS: Imatinib Adjuvant therapy could significantly prolong the RFS of patients with high-risk GISTs. Extended Imatinib adjuvant treatment strategy may further reduce the risk of relapse with a low drug resistance rate and toxicity profile.