- Radiotherapy: ≥ 2 weeks for local palliative XRT (small port); ≥ 6 months must have elapsed if prior TBI, craniospinal XRT; ≥ 3 months must have elapsed if ≥ 50% radiation of pelvis; ≥ 6 weeks must have elapsed if therapeutic doses of MIBG or other substantial BM irradiation was given