Table 3.
Prognostic factors for local control (LC), Locoregional control (LRC) and metastasis-free survival (MFS)
| Local relapse | Locoregional relapse | |||
|---|---|---|---|---|
| Variable | Subhazard Ratio (SHR, 95% CI) | p-value | Subhazard Ratio (SHR, 95% CI) | p-value |
| Gender | ||||
| Male (n = 35) | 1 | p = 0.2 | 1 | p = 0.5 |
| Female (n = 11) | 0.5 [0.1–1.6] | 0.7 [0.3–1.9] | ||
| Histology | ||||
| Non squamous (n = 24) | 1 | p = 0.3 | 1 | p = 0.9 |
| Squamous (n = 22) | 1.48 [0.6–3.2] | 0.9 [0.5–1.7] | ||
| Age | ||||
| < 66 years (n = 23) | 1 | p = 0.4 | 1 | p = 0.9 |
| ≥ 66 years (n = 23) | 1.4 [0.5–3.7] | 0.9 [0.5–2] | ||
| Period between irradiations | ||||
| > 24 months (n = 20) | 1 | p = 0.8 | 1 | p = 0.1 |
| ≤ 24 months (n = 25) | 1.1 [0.4–2.9] | 1.8 [0.8–3.9] | ||
| Missing value (n = 1) | ||||
| > 12 months (n = 36) | 1 | p = 0.8 | 1 | p = 0.5 |
| ≤ 12 months (n = 9) | 1.09 [0.3–3.6] | 1.3 [0.5–3.5] | ||
| Missing value (n = 1) | ||||
| Dose of reirradiation | ||||
| BED > 130 Gy (n = 28) | 1 | p = 0.9 | 1 | p = 0.09 |
| BED ≤130 Gy (n = 18) | 0.9 [0.3–2.5] | 1.8 [0.9–3.9] | ||
| BEDmin ≤50 Gy (n = 22) | 1 | p = 0.16 | 1 | p = 0.06 |
| BEDmin > 50 Gy (n = 23) | 0.5 [0.2–1.3] | 0.5 [0.2–1.05] | ||
| SABR duration | ||||
| ≥ 6 days (n = 25) | 1 | p = 0.4 | 1 | p = 0.7 |
| < 6 days (n = 20) | 1.5 [0.56–4.11] | 0.9 [0.4–1.8] | ||
| Chemotherapy after reirradiation | ||||
| Yes (n = 10) | 1 | 1 | ||
| No (n = 36) | 1.6 [0.4–5.5] | p = 0.4 | 1.6 [0.7–3.9] | p = 0.2 |
| Tumor size | ||||
| < 33 mm (n = 22) | 1 | 1 | ||
| ≥ 33 mm (n = 21) | 1.58 [0.6–4.1] | p = 0.3 | 1.6 [0.8–3.5] | p = 0.18 |
| Missing value (n = 3) | ||||
| GTV Volume | ||||
| < 13 mL (n = 22) | 1 | 1 | ||
| ≥ 13 mL (n = 22) | 1.49 [0.57–3.95] | p = 0.4 | 1.83 [0.87–3.82] | p = 0.10 |
| Missing value (n = 2) | ||||
| SABR duration | ||||
| ≥ 6 days (n = 25) | 1 | p = 0.4 | 1 | p = 0.7 |
| < 6 days (n = 21) | 1.51 [0.56–4.1] | 0.87 [0.42–1.79] | ||
| Number of fractions | ||||
| ≤ 3 (n = 16) | 1 | p = 0.09 | 1 | p = 0.9 |
| > 3 (n = 30) | 2.85 [0.85–9.6] | 0.99 [0.47–2.1] | ||
| Dose per fraction | ||||
| > 12 (n = 23) | 1 | p = 0.8 | 1 | p = 0.2 |
| ≤ 12 (n = 22) | 0.93 [0.35–2.44] | 1.54 [0.74–3.21] | ||
| Performans Status - ECOGa | ||||
| 1 (n = 11) | 1 | p = 0.7 | 1 | p = 0.19 |
| 0 (n = 27) | 0.78 [0.2–2.9] | 1.8 [0.7–4.4] | ||
| Missing value (n = 8) | ||||
| Location of relapse | ||||
| Peripheral (n = 22) Central | 1 | p = 0.03 | 1 | p = 0.9 |
| (n = 24) | 3.2 [1.1–9.5] | 0.9 [0.4–2.1] | ||
| Primary stage (at first irradiation) | ||||
| IIIA (n = 21) | 1 | p = 0.6 | 1 | p = 0.11 |
| IIIB (n = 25) | 1.2 [0.5–3.2] | 1.8 [0.9–3.7] | ||
| In-field relapse | ||||
| No (n = 17) | 1 | p = 0.2 | 1 | p = 0.2 |
| Yes (n = 29) | 2 [0.7–5.9] | 1.6 [0.7–3.6] | ||
| In-field relapse and central tumors | ||||
| No (n = 26) | 1 | p = 0.04 | 1 | p = 0.8 |
| Yes (n = 19) | 2.8 [1.1–7.3] | 0.9 [0.4–1.9] | ||
| Adjuvant chemotherapy | ||||
| No (n = 36) | 1 | p = 0.4 | 1 | p = 0.2 |
| Yes (n = 10) | 1.6 [0.5–5.5] | 1.6 [0.7–3.8] | ||
| GTV coverage | ||||
| < 95% (n = 22) | 1 | p = 0.1 | 1 | p = 0.07 |
| ≥ 95% (n = 24) | 0.45 [0.17–1.18] | 0.5 [0.2–1.06] | ||
| PTV coverage | ||||
| < 90% (n = 23) | 1 | p = 0.17 | 1 | p = 0.04 |
| ≥ 90% (n = 23) | 0.5 [0.19–1.32] | 0.4 [0.2–0.98] | ||
aAt time of stereotactic ablative radiotherapy; ECOG = Eastern Cooperative Oncology Group