We thank Hanjun Ma and colleagues for their interest in our Article1 and their detailed feedback. Ma and colleagues suggest that dietary differences between the Spanish and Polish cohorts might influence the 5-year recurrence-free survival rates and could affect imatinib absorption and efficacy. However, the patients in these cohorts did not receive imatinib, as they received treatment in the pre-imatinib era (ie, before 2001), as stated in our Article.1 Our study used these cohorts for validation by observing post-surgery outcomes without the influence of imatinib treatment.