Is there a difference in risk of secondary cancers from ionizing radiation exposure v/s exposure to chemotherapeutic agents in children? Most of the chemotherapeutic agents help in cure of cancer by causing double-stranded DNA breaks, which result in apoptosis, and same is the mechanism by which ionizing radiation helps cure cancer.

So, why so much stress is laid on protecting children against ionizing radiation exposure (e.g., reducing doses received during diagnostic imaging and using EBRT or radionuclide therapy), but cytotoxic therapies are not viewed with same fright with regard to carcinogenic potential?