Table 2. Factors affecting clinical outcomes after repeated stereotactic radiosurgery, on 30 patients and 36 brain metastasis.
| Univariate analysis | Multivariate analysis | ||
|---|---|---|---|
| p value | p value | HR (95%) | |
| Local control | |||
| Histology (lung vs others, n = 15:15)* | 0.17 | - | |
| WBRT prior to SRS2 (Yes vs No, n = 22:8)* | 0.004 | 0.003 | 0.25 [0.1–0.64] |
| Surgery prior SRS2 (Yes vs No, n = 3:27)* | 0.9 | - | |
| Dose min (≤ 16Gy vs > 16Gy, n = 14:22)Ɨ | 0.01 | - | |
| Vol PTV (< 3cc vs ≥ 3cc, n = 13:23) Ɨ | 0.003 | 0.003 | 0.19 [0.1–0.52] |
| Interval between SRS1/SRS2 (< 1 year vs ≥ 1 year, n = 9:21)* | 0.16 | - | |
| Regional control | |||
| Number of brain metastases (1 vs > 1, n = 20:10)* | 0.1 | 0.04 | 2.97 [1.04–8.51] |
| Extracranial disease (Yes vs No, n = 10:20)* | 0.5 | - | |
| WBRT prior to SRS2 (Yes vs No, n = 22:8)* | 0.01 | - | |
| Overall survival | |||
| Histology (lung vs others, n = 15:15)* | 0.6 | - | |
| Status of disease (complete response vs other, n = 15:15)* | 0.1 | - | |
| DS GPA (≤ 1.5 vs ≥ 2–2.5, n = 6:24)* | 0.8 | - | |
| KPS (≤ 70 vs > 70, n = 4:26)* | 0.8 | - | |
| Interval between SRS1/SRS2 (< 1 year vs ≥ 1 year, n = 9:21)* | 0.6 | - | |
| Toxicities | |||
| Dose min (≤ 15Gy vs > 15Gy, n = 10:26) Ɨ | 0.2 | - | |
| Long PTV (≤ 30 mm vs > 30 mm, n = 10:26) Ɨ | 0.33 | - | |
| Vol PTV (< 7cc vs ≥ 7cc, n = 22:14) Ɨ | 0.05 | - | |
* Patients characteristics
Ɨ brain metastasis characteristics