Ablative radiation for bone mets sure seems like a safe option to improve durability of symptomatic disease control for patients who are living longer than ever. But what are the stats? Here is a look at 373 patients receiving ablative radiation for 505 non-spine bone mets in Toronto. There were 3 cases (0.6%) of grade 3+ toxicity: one G3 osteonecrosis, one G3 neuropathy, and one fatal ileal fistula. Local recurrence occurred in 8% at one year and 14% at two years, with highest risk seen among lytic mets (HR = 2.18), bigger targets (HR = 4.32 if PTV ≥ 54 cc), and receipt of a lower radiation dose (HR = 1.11 per 5 Gy decrease in biologically effective dose). Pathologic fracture at treatment site occurred in 6% at one year and 11% at two years, with highest risk among those with lytic (HR = 3.43) or mixed lytic/sclerotic (HR = 2.70) mets or rib mets (HR = 2.68). | Nguyen, Radiother Oncol 2023
