Table 3.
BMs characteristics in relation to the occurrence of symptomatic radionecrosis stratified for SRS modality
| Whole cohort | Arm-A | Arm-B | |
|---|---|---|---|
| Symptomatic RN (G2-G3) | 56 | 29 | 27 |
| Median occurrence time months (range months) | 10.3 (1.2–54.8) | 6.9 (1.2–32.3) | 15.9 (4.9–54.8) |
| Median volume cm3 (range cm3) | 3.1 (0.04–13.6) | 2.7 (0.04–13.6) | 3.2 (1.1–13.6) |
| G2 RN | 44 | 24 | 20 |
| Median occurrence time months (range months) | 9.9 (1.2–54.8) | 7.5 (1.2–32.3) | 14.2 (4.9–54.8) |
| Median volume cm3* (range cm3) | 3.2 (0.04–13.6) | 2.5 (0.04–10.0) | 4.8 (1.1–13.6) |
| Doses delivered | |||
| 20 Gy | 10 | 10 | 0 |
| 24 Gy | 34 | 14 | 20 |
| G3 RN | 12 | 5 | 7 |
| Median occurrence time months (range months) | 24.1 (2.5–44.9) | 3.9 (2.5–14.6) | 35.6 (16.5–44.9) |
| Median volume cm3* (range cm3) | 2.0 (0.6–13.6) | 3.4 (0.6–13.6) | 1.9 (1.1–13.6) |
| Doses delivered | |||
| 20 Gy | 1 | 1 | 0 |
| 24 Gy | 11 | 4 | 7 |
| Predictors of symptomatic RN occurrence | |||
| Maximum BM diameter |
p << 0.001 HR 2.2 [95% CI 1.6–3.1] |
p << 0.001 HR 4.4 [95% CI 2.5–7.8] |
p = 0.059 HR 1.8 [95% CI 1.0–3.4] |
| Target volume |
p << 0.001 HR 1.1 [95% CI 1.0–1.2] |
p << 0.001 HR 1.4 [95% CI 1.3–1.5] |
p = 0.076 HR 1.1 [95% CI 1.0–1.1] |
SRS, Radiosurgery; RN, Radionecrosis; G2, Grade two; G3, Grade three; SRS, Radiosurgery
*At BMs treatment time