Clinical characteristics, treatment modalities, and oncological outcomes in patients with gastrointestinal stromal tumors in Mexico.

Abstract

e23514 Background: In Mexico there is scarce information regarding treatment and outcomes of patients with gastrointestinal stromal tumors (GIST). Access to medical therapy in a country with limited resources may impact survival. We aim to report clinical characteristics, treatment modalities, and oncological outcomes in patients with GIST treated at our institution. Methods: Single-center retrospective review of patients with histologically confirmed diagnosis of GIST evaluated between Jan 2005 to Dec 2018. Overall survival (OS) was estimated by Kaplan-Meier curves and compared with log-rank rest. A p value < 0.05 was significant. Results: 90 cases were included with a median age of 57 years, 61% were women. Most common symptoms were gastrointestinal bleeding (68%), abdominal pain (58%) and anemic syndrome (54%). Primary tumor location was stomach (51%), small intestine (43%) and other locations (6%). 89% (n 80) were localized and 11% (n 10) metastatic. For localized tumors, Fletcher risk stratification was used to predict prognosis. We found 44% low, 29% intermediate and 27% high-risk. Treatment for localized patients was: initial surgery (95%, n76), neoadjuvant imatinib (5%, n4). Adjuvant imatinib was given to only 69% of patients that required it (31 of 45 patients with intermediate or high-risk), 12.5% (n12) of patients with localized disease had recurrence (2 of them did not receive adjuvant treatment). In the advanced seating (n10), most common site of metastasis was liver 70%. Initial treatment was surgery in 6 patients. Only 5 patients received imatinib (50% of those who required it). Only one patient had second line sunitinib. None had access to regorafenib, none had a molecular analysis performed. Survival outcomes are shown in table. Conclusions: Patients with localized GIST treated at our institution have good oncological outcomes and similar to those reported by other series. On the other hand, patients with advanced disease have inferior outcomes compared to those reported by other series possibly related to limited access to treatment. [Table: see text]