M. Le Deley

We designed a multicenter randomized trial comparing chemotherapy with daunorubicin-Ara C (chemotherapy group) and all transretinoic acid (ATRA) combined to the same chemotherapy (ATRA group) in newly diagnosed APL patients aged 65 years or less. The major endpoint of the study was event-free survival (EFS) ("events" being defined as failure to achieve complete remission [CR], occurrence of relapse, or death in CR). Early termination of the trial was decided after the first interim analysis, as EFS was significantly higher in the ATRA group. At the time, 101 patients had been randomized (54 in the ATRA group and 47 in the chemotherapy group). In the ATRA group, 49 (91%) patients achieved CR, 5 (9%) had early death, and 0 had resistant leukemia, compared with 38 (81%), 4 (8%), and 5 (10%) patients, respectively, in the chemotherapy group. The difference in CR rate between the two groups was not significant. The duration of coagulopathy was significantly reduced in the ATRA group, compared with the chemotherapy group. In the ATRA group, six patients relapsed after 7 to 15.5 months. In the chemotherapy group, 12 patients relapsed after 1 to 16 months, and 2 died in CR. Kaplan-Meier EFS was estimated at 79% +/- 7% and 50% +/- 9% at 12 months, respectively, in the ATRA and the chemotherapy group (P = .001). Kaplan-Meier estimate of relapse was 19% +/- 8% and 40% +/- 12% at 12 months (P = .005). In conclusion, ATRA followed by chemotherapy increases EFS in newly diagnosed APL. These results strongly suggest that ATRA should be incorporated in the front line therapy of newly diagnosed APL.

We designed a multicenter randomized trial comparing chemotherapy with daunorubicin-Ara C (chemotherapy group) and all transretinoic acid (ATRA) combined to the same chemotherapy (ATRA group) in newly diagnosed APL patients aged 65 years or less. The major endpoint of the study was event-free survival (EFS) (“events” being defined as failure to achieve complete remission [CR], occurrence of relapse, or death in CR). Early termination of the trial was decided after the first interim analysis, as EFS was significantly higher in the ATRA group. At the time, 101 patients had been randomized (54 in the ATRA group and 47 in the chemotherapy group). In the ATRA group, 49 (91%) patients achieved CR, 5 (9%) had early death, and 0 had resistant leukemia, compared with 38 (81%), 4 (8%), and 5 (10%) patients, respectively, in the chemotherapy group. The difference in CR rate between the two groups was not significant. The duration of coagulopathy was significantly reduced in the ATRA group, compared with the chemotherapy group. In the ATRA group, six patients relapsed after 7 to 15.5 months. In the chemotherapy group, 12 patients relapsed after 1 to 16 months, and 2 died in CR. Kaplan-Meier EFS was estimated at 79% +/- 7% and 50% +/- 9% at 12 months, respectively, in the ATRA and the chemotherapy group (P = .001). Kaplan-Meier estimate of relapse was 19% +/- 8% and 40% +/- 12% at 12 months (P = .005). In conclusion, ATRA followed by chemotherapy increases EFS in newly diagnosed APL. These results strongly suggest that ATRA should be incorporated in the front line therapy of newly diagnosed APL.

9517 Background: Anthracyclines and alkylating agents are the main effective drugs known for ES. Ifosfamide and cyclophosphamide are widely used, have different toxicity profiles and unknown relative efficiency. The Euro-EWING.99-R1 trial compared, in SR localized ES, two consolidation regimens combining either ifosfamide or cyclophosphamide with vincristine and D-actinomycin (VAI vs VAC) given after an intense induction CT containing vincristine, ifosfamide, doxorubicin and etoposide (VIDE) (NCT00020566). Methods: SR tumors were localized ES with either a good histological response to VIDE chemo (<10% cells), or small tumors (< 200 ml) resected at diagnosis or receiving radiotherapy alone as local treatment. Pts entered the trial after 6 VIDE + 1 VAI courses. Allocated treatment was either 7 VAI courses with ifo = 6 g/m²/course or 7 VAC courses with cyclo = 1.5 g/m²/course. Randomization was stratified by gender, age, local treatment and data center. It was a non-inferiority trial comparing VAC to VAI with a limit of non-inferiority set at -8.5% for 3-y event-free survival rate (EFS). Overall, 806 pts were required to achieve 80%-power with 1-sided alpha = 5%. 91.4%-confidence intervals (CI) are given for this final analysis performed after 3 interim analyses. Results: 856 pts were recruited between 02/2000 and 08/2010 in 202 European pediatric and adult oncology centers in 11 countries: 424 VAI and 432 VAC. With a median FU of 4.6 y, the main results were: 3-y EFS = 77.1 and 76.0% respectively, 3-y EFS difference = -1.1% (-6.3; +4.2), hazard ratio (HR) of event = 1.06 (0.83; 1.36), HR of death = 1.05 (0.78; 1.41) (intention to treat). Results were stable on the per protocol population. Major modifications of CT were significantly more frequent in the VAI arm (13%) than in the VAC arm (6%) due to toxicity but also to an inferior compliance. We observed more thrombocytopenia in the VAC arm but more grade 2-4 acute tubular renal toxicity in the VAI arm (31 vs 16%). Conclusions: Cyclophosphamide and ifosfamide have a similar efficacy in consolidation treatment of standard risk Ewing sarcoma. Late effects studies are on-going to compare renal and gonadal toxicity of both arms.