Supportive / QoL
2026-10-24 ESMO Congress 2026
Nonspine Bone Metastases SBRT Practice Patterns
ForNonsurgical nonspine bone metastases considered for SBRT
TL;DR35 Gy/5 most often chosen (29/99 responses); 40 Gy/5 acceptable to 8 or 9 of 9 experts wherever listed; every schedule BED ≤100 Gy10.
The site-specific rejections are the RT read: 20 Gy/1 lost majority support in the humerus, acetabulum and femur cases, and 50 Gy/5 in the humerus and acetabulum, while 40 Gy/5 stayed acceptable to 8 or 9 of 9 wherever listed. For weight-bearing or periarticular targets, that favors moderate 5-fraction schedules over single fraction.
For a nonsurgical nonspine bone met irradiated >3 months ago, this survey supports dose de-escalation (all 9 experts after prior SBRT, 7 of 9 after prior cRT); it does not address spine targets or postoperative bone. The longer read
Site drives the objections: a majority rejected 20 Gy/1 in the humerus, acetabulum and femur cases and 50 Gy/5 in the humerus and acetabulum, while 40 Gy/5 kept 8 or 9 of 9 votes everywhere listed. For weight-bearing or periarticular NSBM, moderate 5-fraction schedules have the broadest expert backing.
14 details
Two-round survey of 9 international radiation oncologists chosen for NSBM-SBRT expertise, covering 11 cases with planning CT, MRI and GTV contours supplied. Round 2 rated each proposed schedule acceptable / not recommended / no opinion and picked 2 preferred schedules; majority defined as ≥5 of 9. Completion was 100%.
Nonsurgical nonspine bone metastases across long bones, pelvis and thorax, with RCC, breast, NSCLC and prostate primaries; some cases carried an extraosseous component.
6 experts prescribed one dose volume, 3 used an SIB with GTV/CTV or nested CTV1/CTV2 volumes. Schedules spanned 18-24 Gy/1 to 42-50 Gy/10, all at BED ≤100 Gy10.
35 Gy/5 was chosen most (29 of 99 responses), and 40 Gy/5 was the most widely accepted. Scapula was the only case where every schedule had majority acceptance. Humerus, acetabulum and femur were the only cases where a majority rejected one or more schedules.
| Schedule | BED (Gy10) | Use |
|---|---|---|
| 35 Gy/5 | 60 | Most common: 29 of 99 responses (29%); 5 experts in ≥1 case |
| 20 Gy/1 | 60 | ≥3 experts |
| 30 Gy/3 | 60 | ≥3 experts |
| 30 Gy/5 | 48 | ≥3 experts |
| Case | Not recommended by majority |
|---|---|
| Humerus (RCC) | 20 Gy/1 · 50 Gy/5 |
| Acetabulum (breast) | 20 Gy/1 · 50 Gy/5 · 8 Gy/1 + 18 Gy/1 SIB |
| Femur (NSCLC) | 20 Gy/1 |
The ≤100 Gy10 ceiling sits below the BED >100 Gy10 recommended for lung and liver SBRT. The cited Erler series reported LC 95% and 87% at 6 and 24 mo after 30-35 Gy/5, with 8.5% fracture at a median 2.5 mo; a second series of 85 NSBM reported 1-yr LC 92%.
BED equivalence assumes α/β 10 across histologies, which the authors concede may not hold for breast and prostate. Health-system and resource differences across the panel may drive part of the variation attributed to judgment.
The heterogeneity is real but bounded: a moderate-BED, 5-fraction working range emerges, and caution concentrates on weight-bearing long bones and joints. The optimal dose balancing LC and fracture stays unknown, and the authors call for phase I dose-finding and comparative trials.
Expert practice survey (n=9) with acceptability ratings; no formal consensus process and no clinical outcomes, so it maps opinion rather than testing efficacy.
- Upper dose threshold balancing LC and fracture in NSBM-SBRT
- Predictors of fracture after nonspine bone SBRT
- Toxicity profile of salvage NSBM-SBRT reirradiation
📚 Sources · 📄 1 paper
Single-Fraction SBRT vs Multifraction RT for Nonspine Bone Metastases NCT02163226
ForPainful, predominantly nonspine bone mets, life expectancy >3 mo, no prior RT
TL;DR3-mo ITT pain response 38% vs 21% (P=.05) with 12-16 Gy single-fraction SBRT vs 30 Gy/10; 2-yr local PFS 100% vs 75.6%.
Dose, not single fraction per se, carries the pain signal: 3-mo ITT response was 62% (13 of 21) with 16 Gy vs 30% (18 of 60) with 12 Gy, and 12 Gy tracked 30 Gy/10 at 9 mo (13.3% vs 15.2%). Because 16 Gy went to smaller lesions, the dose choice remains hypothesis-level.
In a pt with a painful nonspine bone met, good performance status and longer expected survival, this supports single-fraction SBRT as a reasonable alternative to 30 Gy/10; it does not test SBRT against an 8 Gy single fraction or extend to spine lesions, cord compression or pathologic fracture. The longer read
Dose carries the pain signal: 3-mo ITT response was 62% (13 of 21) with 16 Gy vs 30% (18 of 60) with 12 Gy, and 12 Gy tracked 30 Gy/10 at 9 mo. Local failure was 0% with SBRT at 24 mo, but 16 Gy went to smaller lesions, so the dose pick is hypothesis-level.
14 details 2 trials watching
Phase 2, nonblinded, randomized noninferiority trial at one institution, 1:1, N=160 (81 SBRT, 79 MFRT). Stratified by tumor size, bone site and number of sites irradiated. Enrolled September 2014 to June 2018.
Pathologic cancer diagnosis, painful bone mets (score ≥2 of 10), age ≥18, life expectancy >3 mo; up to 3 fields allowed. Excluded prior RT to the site, untreated cord compression, pathologic fracture at the site, and recent radioisotope.
SBRT 12 or 16 Gy x1 by lesion size (4 cm cutoff) vs 30 Gy in 10 fx. PTV = GTV + 5 mm, no CTV; 2D/3D, IMRT or VMAT delivery. Prophylactic 7-day low-dose dexamethasone recommended for SBRT only.
Primary: pain response by international consensus criteria (pain score plus MED), noninferiority margin 10%. Secondary: MDASI QoL, CTCAE toxicity, local control, OS.
No toxicity differences between arms. G3 fatigue 9.9% vs 5.1% (P=.37), fracture 1.2% vs 0% (P=.99); MDASI scores improved in both arms without a difference.
Prior randomized trials found no pain difference between single and multifraction conventional courses, with more retreatment after 8 Gy. RTOG 9714 and the Dutch Bone Metastasis Study are the conventional-dose trials behind that equivalence. This trial escalates the single fraction but never tests it against 8 Gy.
Dexamethasone given asymmetrically to SBRT pts confounds early pain response. The 16 vs 12 Gy contrast is non-randomized and tracks lesion size. Five SBRT pts did not receive treatment due to insurance denial, and median OS of 6.7 mo leaves few pts at risk for late local failure.
The ITT data support noninferiority and a local-control advantage for SBRT; the superiority read depends on per-protocol denominators. The live question is 16 Gy vs 8 Gy in pts selected for longer survival, which needs a phase 3.
| Analysis · timepoint | SBRT | MFRT | P |
|---|---|---|---|
| ITT · 1 mo | 44% (n=36) | 30% (n=24) | .18 |
| ITT · 3 mo | 38% (n=31) | 21% (n=17) | .05 |
| Per-protocol · 2 wk | 34 of 55 (62%) | 19 of 52 (36%) | .01 |
| Per-protocol · 3 mo | 31 of 43 (72%) | 17 of 35 (49%) | .03 |
| Per-protocol · 9 mo | 17 of 22 (77%) | 12 of 26 (46%) | .04 |
| Timepoint | 16 Gy x1 | 12 Gy x1 | 30 Gy/10 | P |
|---|---|---|---|---|
| 3 mo | 62% (13 of 21) | 30% (18 of 60) | 21% (17 of 79) | .003 |
| 9 mo | 42.9% (9 of 21) | 13.3% (8 of 60) | 15.2% (12 of 79) | .005 |
| Endpoint | SBRT | MFRT | P |
|---|---|---|---|
| 1-yr local PFS | 100% | 90.5% | .01 (curve) |
| 2-yr local PFS | 100% | 75.6% | .01 (curve) |
| 24-mo cumulative local failure | 0% | 9.7% | .02 |
| 2-yr reirradiation | 0% | 5.3% | .10 |
CONSORT flow
Single-institution randomized phase 2 with one-sided alpha 0.20; superiority signals are per-protocol amid heavy attrition, comparator 30 Gy/10 rather than 8 Gy. Authors call for phase 3.
- Does 16 Gy SBRT beat 8 Gy single fraction for pain?
- Phase 3 confirmation of SBRT pain response in nonspine bone mets recruiting A Phase III Randomized Trial Comparing Stereotactic Body Radiation Therapy (SBRT) vs Conventional Palliative Radiation Therapy for Painful Bone Metastases Phase 3n=220 · primary completion 2027-06 · phase 3 SBRT dose levels vs conventional palliative RTrecruiting Stereotactic Body Radiotherapy vs Conventional Palliative Radiotherapy for Painful Non-Spine Bone Metastases Phase 3n=230 · primary completion 2027-07 · phase 3 SBRT vs conventional RT, non-spine pain relief
- Which pts live long enough to gain from SBRT local control?
📚 Sources · 📄 1 paper
2026-05-30 ASCO Annual Meeting 2026
SPIN Score (Celiac Plexus Radiosurgery) NCT03323489
ForPancreatic cancer with retroperitoneal pain considered for celiac plexus SRS
TL;DRPost-hoc predictors of pain response after celiac SRS: response 32% / 53% / 89% by 0 / 1 / 2 SPIN points.
The actionable RT read is timing, not technique: neurotoxic chemo exposure carried OR 5.1 (p=0.009) against response, so the referral decision moves earlier in the disease course, before oxaliplatin or taxane neuropathy. Celiac SRS is NCCN-listed and single-fraction, so the gate is who you irradiate and when, not dose.
In pancreatic cancer pts with retroperitoneal pain scoring above 6 and no prior neurotoxic chemo, this supports considering celiac SRS earlier rather than after systemic lines; it does not tell you what to do for the chemo-exposed, low-pain pt, where response was 32%. The longer read
The gate on celiac SRS is patient selection and timing, not plan quality: neurotoxic chemo exposure carried OR 5.1 (p=0.009) against pain response, and 2-point pts responded 89% vs 32% at 0 points. Argues for taking the referral early rather than as last-line salvage.
The variable that mattered is one med onc controls: prior neurotoxic chemotherapy predicted failure of celiac SRS (OR 5.1, p=0.009). For a pt with severe retroperitoneal pain, this argues for a celiac SRS referral alongside, not after, an oxaliplatin or taxane backbone.
| SPIN score | n | Pain response |
|---|---|---|
| 0 | 31 | 32% |
| 1 | 40 | 53% |
| 2 | 19 | 89% |
10 details
Post-hoc analysis of the pivotal single-arm phase 2 celiac plexus radiosurgery trial (NCT03323489), n=90 evaluable. Candidate baseline predictors screened by univariate then multivariate logistic regression, with only multivariate-significant variables carried into the score. Internal validation by bootstrap resampling, 500 iterations, for an optimism-corrected AUC.
Pain response per parent protocol: a ≥2-point reduction in average pain on the Brief Pain Inventory-Short Form, baseline to three weeks. Parent-trial response was 53% (95% CI 42-64%).
Only neurotoxic chemotherapy exposure (OR 5.1, p=0.009) and baseline pain intensity (OR 1.8, p=0.003) survived multivariate analysis; age and therapy line dropped out to collinearity. The resulting 2-point score separated response into 32% / 53% / 89%, with AUC 0.716 apparent, 0.714 optimism-corrected.
| Predictor | Univariate | Multivariate |
|---|---|---|
| Neurotoxic chemo exposure | OR 5.33 (2.13-13.4), p<0.001 | OR 5.1, p=0.009 |
| Baseline pain intensity | OR 1.73, p=0.003 | OR 1.8, p=0.003 |
| Age | OR 1.06, p=0.014 | lost significance |
| Therapy line | OR 0.65, p=0.04 | lost significance |
The score was derived and internally validated in the same 90 pts, so the bootstrap corrects optimism from resampling but not from the variable-selection step that preceded it. The 2-point stratum is n=19, and the dichotomy at pain >6 was picked from the same data that shows steeper response above 7 and 8.
The neurotoxic-chemo term is the interesting one because it is a timing variable a clinician controls, not a fixed patient trait: it implies referral for celiac SRS competes with the systemic sequence rather than following it. Whether that reflects true nerve injury blunting an ablative pain response, or confounding by later-line disease biology, the post-hoc design cannot separate.
Post-hoc derivation on the parent trial's own 90 pts; internal bootstrap only, no external cohort. Design dominates the read regardless of effect size.
- External validation of the SPIN score in an independent cohort
- Is neurotoxic chemo effect causal or a proxy for later-line disease
- Durability of pain response beyond the 3-week endpoint
📚 Sources · 🐦 1 tweet
Celiac SRS = convenient, effective tx for intractable pain, but who benefits most?
— Dr. Nina Niu Sanford (@NiuSanford) May 30, 2026
Post-hoc Ph2 analysis identified 2 response predictors (SPIN score): severe baseline pain & no prior neurotoxic chemo.
Supports earlier use before potential chemo neuropathy. #ASCO26 @OncoAlert pic.twitter.com/3qFYU6N1iD