Despite remarkable treatment advances in childhood cancer in the past few decades that have resulted in a survival rate of more than 80% for childhood cancers in high-income countries, the survival rate among children with cancer in low- and middle-income countries can be as low as 10% in some settings,
1 with a wide variability in survival by cancer type. Limited options usually remain when the malignant tumor progresses after 1 or 2 lines of a standard chemotherapy protocol. Repetitive administration of conventional chemotherapy at the maximum tolerated dose imposes many adverse effects that further limit dosing and quality of life. The goal of the oncologist at this point remains mainly palliative, with an effort to halt the progression of cancer and improve quality of life. Often the only therapy offered is best supportive care, which includes treatment of pain and other associated problems without any definite therapy for cancer control.