KEY POINTS
- BONY-M was a prospective multicentre phase 2 study across six centres, with 67 evaluable patients with oligometastatic disease involving at least one bone metastasis. Common primary cancers were prostate (33%), breast (28%), kidney (15%), and lung (10%).
- Bone metastases were treated with SABR using 30 Gy or 37.5 Gy in 3 fractions. The trial had previously reported 92% 1-year local control; this analysis focused on longitudinal quality of life and pain.
- Most patients had little or no pain at baseline: 44/66 (67%) had a numeric pain score of 0–1, while 22 were classified as symptomatic with scores ≥2.
- Mean EQ-5D-5L quality-of-life index remained essentially unchanged from 0.87 at baseline to 0.87 at 52 weeks. Mean visual analogue scale score was 77 at baseline and 73 at 52 weeks, with no significant overall time-dependent deterioration.
- Among symptomatic patients, overall pain response was 50% at 12 weeks, 59% at 24 weeks, and 41% at 52 weeks. Mean pain score fell by 2.3 points at 24 weeks (95% CI 1.4–3.2; p<0.001) and 1.92 points at 52 weeks (95% CI 1.05–2.79; p<0.001).
- Pain flare at two weeks occurred in only 7/66 patients (11%). Four symptomatic fractures occurred within treated volumes, including grade 3 vertebral compression and acetabular fractures; the latter required surgery.
- Interpretation of quality-of-life trajectories is complicated by subsequent cancer treatment: during follow-up, 37% received new systemic therapy and 24% new local therapy, making it difficult to isolate the contribution of bone SABR itself.
CLINICAL TAKEAWAY
For carefully selected patients with oligometastatic bone disease, ablative SABR appears compatible with preservation of overall quality of life while providing meaningful pain relief when metastases are symptomatic. The results are reassuring rather than practice-changing because this was a single-arm secondary endpoint analysis with substantial competing treatment during follow-up.