Get on with it.

NCCN is pretty specific on the timing of local therapy following induction chemo for Ewing sarcoma: at 12 weeks when using VAC/IE and at 18 weeks when using VIDE. This NCDB analysis is for all those who ever wondered “Why be so specific?” It measured the impact of local therapy timing on survival outcomes by dividing over 1300 patients treated for Ewing sarcoma between 2004-2014 into (of course) two binary groups, those receiving local therapy 6-15 versus 16-30 weeks after initial chemo. Rates of overall survival at 10 years were 70% with early versus 57% with later local treatment. Not surprisingly, some generally poor prognostic factors were associated with patients receiving later local treatment: they were older, less likely to have disease <8 cm, less likely to receive surgery, and less likely to have private insurance / more likely to be in the lowest income bracket. Even so, timing of local therapy persisted as one of the biggest predictors of survival on multivariate analysis  TBL: There are a whole lotta potential biases here, but don’t hold initiation of local therapy to discuss them all because total package time of treatment for Ewing sarcoma seems to matter. | Lin, Int J Radiat Oncol Biol Phys 2019