Background/Introduction:
Infants with MYCN amplified (MYCN-A) neuroblastoma treated in INES 99.4 (Canete et al, JCO 2009) showed a very dismal prognosis. Therefore, SIOPEN decided to submit these infants to the HR-NBL1/SIOPEN intensified treatment .
Methods and population:
94 MYCN-A infants (58 males, 36 females) were considered eligible, (75% stage 4; 13% stage 2-3, 12% 4s) with a median age of 8.5 months. All received induction chemotherapy (IC: Rapid-Cojec ± TVD) followed by BuMel/SCT, primary site surgery, radiation (21Gy) and 13-cisRA as maintenance. 35 received antiGD2 ch14.18/CHO treatment since 2010. Median follow up time is 3.9 years. In 99.4 trial, 35 patients (20 males, 15 females; median age 7,6 months) were analyzed (69% stage 4, 28% stage 4s and 3% stage 3). Treatment consisted in standard IC (carboplatin&etoposide-CADO), surgery, BuMel/SCT, local radiotherapy, 13-cisRA maintenance (JCO 2009).
Results: For HR-NBL1, 85% of evaluable cases (n=80) achieved CR/VGPR/PR following IC. Six infants went off treatment, one had PD whilst five had less than PR. The EFS and OS rates are 0.44±0.06 and 0.48±0.06 for all 94 MYCN-A infants. The 5 yr EFS and OS rates were 0.4 and 0.45 for stage 4; 0.51 and 0.51 for stage 2&3, 0.58 and 0.65 for stage 4s (NS). The main cause of death remained progression/relapse, while only 4 cases were due to toxicity. For 99.4 population, 30% of patients progressed/did not respond to IC, with median time to progression of 4 months. The 2y-OS was 28% (SD: 0.15), 2y-EFS 24% (SD:0,11) , 12 months median survival time.
Conclusions: Rapid-Cojec resulted in less disease progressions and better response rate than 99.4 IC. Although OS and EFS improved in HR-NBL1/ SIOPEN as compared to 99.4, it is below 50% with lack of disease control being the main cause of death. The number of infants treated with ch14.18/CHO is too small to conclude currently and will be further addressed.