GEIS-21: a multicentric phase II study of intensive chemotherapy including gemcitabine and docetaxel for the treatment of Ewing sarcoma of children and adults: a report from the Spanish sarcoma group (GEIS)
Mené sur 43 patients âgés de moins de 40 ans et atteints d'un sarcome d'Ewing à haut risque récemment diagnostiqué (âge médian : 17 ans), cet essai de phase II évalue l'efficacité, du point de vue du taux de réponse objective, de la survie sans progression et de la survie globale, et la toxicité d'une chimiothérapie combinant gemcitabine et docétaxel (durée médiane de suivi : 43,4 ans)
Background: First Spanish trial of Ewing sarcoma (ES) including adults and children with the aim to test the efficacy of Gemcitabine and Docetaxel (G/D) in newly diagnosed high-risk (HR) patients. Methods: This was a prospective, multicentric, non-randomised, open study for patients less than or equal to40 years with newly diagnosed ES. HR patients (metastatic, axial-pelvic primaries or bone marrow micrometastasis) received 2 window cycles of G/D. Patients with an objective response (OR) to G/D received 12 monthly cycles of G/D after completion of mP6. The primary end point was the OR rate to the G/D window phase and the event-free survival (EFS) and overall survival (OS) for all patients. The study is registered at ClinicalTrials.gov (identifier: NCT00006734). Results: Forty-three patients were enroled, median age 17 years (range, 3–40). After a median follow-up of 43.4 months, the 5-year OS rate is 55.0% (95% CI, 41–74%) with an EFS of 50.0% (95% CI, 36–68%). The 5-year OS and EFS rates for standard risk (SR) patients was 76.0% (95% CI, 57–100%) and 71.0% (CI, 54–94%); for HR 36.0% (CI, 20–65%) and 29.0% (CI, 15–56%). Twelve of 17 (70.6%) high-risk (HR) patients showed an OR (7 PR and 5 SD) to G/D window therapy. The 5-year OS rate for patients less than or equal to18 years of age was 74.0% (CI, 56–97%) and 31.0% for >18 years (95% CI, 15–66%), P<0.001. Grade 4 adverse events during mP6 occurred in 28/39 of patients (72%) and did not correlate with age. Multivariate survival analyses with <18 vs greater than or equal to18 and risk groups significant differences, P<0.00001. Using a Cox model for OS, both age and risk group were statistically significant (P=0.0011 and P=0.0065, respectively). Conclusions: Age at diagnosis is an independent prognostic factor superior to the presence of metastases with 18 years as the strongest cut-off. The mP6 regimen provided survival curves that plateau at 3 years and G/D produced significant responses in HR-ES that is worth further exploring.