Patients with primary localized high-grade sarcomas of the digestive tract excluding GIST : a retrospective study from the French sarcoma group

Introduction : The natural history of localized high-grade sarcomas of the digestive tract (SDT) excluding GIST has been rarely considered owing to their low incidence and heterogeneity. We describe the histoclinical characteristics of SDT and correlate them with patients' outcomes. Methods : We retrospectively collected medical files from a European database covering connective tissue tumors listed in Europe for about twenty years. Only untreated localized primary high-grade SDT were included. A central histological review was performed for each case. Patients' characteristics were compared and correlated with clinical outcomes. Results : A total of 45 patients were identified. Leiomyosarcomas (LMS) and undifferentiated sarcomas (UDS) were predominant, the former having better overall survival (OS) and progression- free survival (PFS) while the latter having a worse outcome than the other histological types. Complete remission was obtained in 34 patients (75%) and was associated with male sex, age over 40 years and monofocal tumor. Complete surgery and LMS histology were associated with a better prognosis without any significant difference in baseline characteristics or in treatment modalities. Conclusion : Complete surgery and histological type seem to be prognostic indicators of SDT. These results suggest the importance of treating these patients in a reference center. (Acta gastroenterol. belg., 2017, 80, 481-486).