45 Gy is not sufficient radiotherapy dose for Group III orbital embryonal rhabdomyosarcoma after less than complete response to 12 weeks of ARST0331 chemotherapy: A report from the Soft Tissue Sarcoma Committee of the Children's Oncology Group.

For patients with Group III orbital ERMS achieving a CR following VAC chemotherapy that includes modest dose CPM, 45 Gy may be sufficient for durable failure-free survival. However, for those with <CR treated with the ARST0331 systemic therapy, a different local therapy approach may be needed to achieve the control rate of IRS-IV without its toxicity.