Using the recurrence risk score by Joensuu to assess patients with gastrointestinal stromal tumor treated with adjuvant imatinib: A retrospective cohort study

In 2014, Joensuu and colleagues devised the first recurrence risk score (RRS) to identify the risk factors for gastrointestinal stromal tumor (GIST) recurrence. However, there are scarce data available on RRS effectiveness and efficiency. Therefore, we retrospectively analyzed clinical data to validate Joensuu's RRS in patients treated with adjuvant imatinib. In this retrospective cohort study, data were collected from patients with GIST who were treated with adjuvant imatinib between December 2005 and May 2017 in the West China Hospital. The study consisted of 137 patients, after application of inclusion and exclusion criteria. Recurrence-free survival (RFS) was the primary end point. The RRSs for 137 patients were divided into 3 groups: low (n = 46), medium (n = 48), and high (n = 43). The RFSs of the 3 groups were significantly different (P < .001). In patients who received adjuvant imatinib for <36 months, the RFS difference was also significant (P < .001), and the result was similar in patients treated with adjuvant imatinib for ≥36 months (P = .03). The area under the curve of the RRS was 0.84 ([95% confidence interval] 0.76–0.92, P < .001), suggesting that the RRS method could accurately assess recurrence risks for patients with GIST who were treated with adjuvant imatinib. It is appropriate to apply the RRS method to assess recurrence risks for patients with GIST who were treated with adjuvant imatinib. A longer adjuvant imatinib duration is recommended for high-risk patients with GIST. It is also important to identify a more effective treatment for patients who are resistant to imatinib.