ATRT-05. RESULTS OF MULTICENTER TRIAL CONCERNING THE TREATMENT OF CHILDREN WITH ATYPICAL TERATOID/RHABDOID TUMORS (ATRT) OF THE CENTRAL NERVOUS SYSTEM

We analyzed 105 patients under 18 years. The median age was 21 months. There were 54 boys and 51 girls. The supratentorial tumors were in 53 patients, infratentorial in 48, and in spinal cord in 4. 60 had stage M0,29-М+and 16-Mx. All the patients got surgical treatment:total tumor removal in 34,subtotal in 37,partial in 30,and biopsy in 4;75 patients got chemoradiotherapy to ATRT-2006;6-CWS;13-EU-RHAB;5-HIT-SKK;individual schemes in 6. RESULTS: 47 are alive,1 was LFU, and 57 died. PFS was 32%±0.05; the five-year OS 40%±0.05. The median survival-30 months, the median progression-free survival-12 months, and the median of follow-up-23 months. PFS was significantly better in patients more than 12 months compared to patients younger than 12 months:40 and 12%;p=0.00161.After total resection PFS was higher compared to subtotal resection, partial resection, and tumor biopsy:48,38,0,and 0%(p=0.025). After chemoradiotherapy, PFS was higher compared to patients without radiotherapy: 49and 0%(р=0.0000000).PFS for stage M0 was higher compared to stage M+and stage Mx:41,15,and 27%,respectively(р=0.00032).PFS was better for the tumors in the spinal cord and infratentorial location compared to the supratentorial location:67,37,and 25%(p=0.0876).The survival rate was higher among the patients who got treatment according to the ATRT-2006 protocol compared to EU-RHAB, individual regimens, CWS, and HIT-SKK:39,19,17,17,and 0% respectively;p=0.00159.The survival was higher among the patients who got intraventricular/intrathecal Methotrexate,Cytarabine, Prednisolone than among the patients who got only Methotrexate or none at all:40,0,and 5%, respectively; p=0.00015. CONCLUSIONS: Survival was significantly better in patients more than 12month, without metastases, with total removal tumor, chemotheradiotherapy by ATRT-2006 protocol with i/t, i/v Methotrexate/Cytarabine/Prednisolone.