X-out the extra.

We first learned at ASTRO 2019 that a boost to residual disease may not be beneficial for patients with high-risk neuroblastoma. Here we have the final publication. In the ANBL0532 treatment paradigm, local radiation was delivered after autologous stem-cell transplant (SCT). The primary treatment volume was the post-induction chemo, pre-operative extent of disease prescribed 21.6Gy/12. Those who had incomplete resection also received a sequential boost of 14.4Gy/8. This analysis wasn’t a head-to-head comparison, so outcomes were compared to the predecessor trial COG A3973 where patients received single SCT and no boost. The main question focused on the subset of patients from ANBL0532 and A3973 who had residual disease and received single SCT and radiation. At 5 years local progression occurred in 16% on ANBL0532 and 11% on A3973, meaning radiation boost did not contribute to the overall trial improvements in event-free (EFS) and overall survival (OS). TBL: An additional radiation boost (from 21.6 → 36 Gy) for residual disease doesn’t improve local control for high-risk neuroblastoma. | Liu, J Clin Oncol 2020