Table 1 Characteristics of patients, primary tumours, oligometastatic tumours and SBRT characteristics
Characteristic | Distribution | Number (%) |
|---|---|---|
All tumours | Â | 1547 |
Sex | Male | 994 (64.3) |
| Â | Female | 553 (35.7) |
Age, years | Median, range, IQR | 72; 16–93; 63–78 |
ECOG Performance Status | 0 | 841 (54.4) |
| Â | 1 | 529 (34.2) |
| Â | 2 | 90 (5.8) |
| Â | 3 | 19 (1.2) |
| Â | Missing | 68 (4.4) |
Primary lesion sites | Lung | 451 (29.2) |
| Â | Colorectum | 391 (25.3) |
| Â | Head and Neck | 126 (8.1) |
| Â | Oesophagus | 132 (8.5) |
| Â | Others | 447 (28.9) |
Pathology of primary lesion | Adenocarcinoma | 861 (55.7) |
| Â | Squamous cell carcinoma | 396 (25.6) |
| Â | Sarcoma | 47 (3.0) |
| Â | Others | 168 (10.9) |
| Â | Missing | 75 (4.8) |
Control method of primary lesion | Surgery | 1222 (79.0) |
| Â | Chemoradiation | 130 (8.4) |
| Â | Radiation (X-ray or particle) | 70 (4.5) |
| Â | Others | 40 (2.6) |
| Â | Missing | 85 (5.5) |
Disease-free interval, months | Median, range, IQR | 17.5; 0–423.9; 8.0–34.3 |
Oligometastatic state | Oligo-recurrences | 1157 (74.8) |
| Â | Sync-oligometastases | 133 (8.6) |
| Â | Unclassified | 133 (8.6) |
| Â | Missing | 124 (8.0) |
SBRT performed institution | Academic | 642 (41.5) |
| Â | Non-academic | 905 (58.5) |
Date SBRT was performed | 2004–2009 | 518 (33.5) |
|  | 2010–2015 | 1029 (66.5) |
Chemotherapy | Before SBRT | Yes, 591 (38.2) No, 945 (61.1) Missing, 11 (0.7) |
| Â | Concurrent with SBRT | Yes, 34 (2.2) No, 1513 (97.8) |
| Â | After SBRT | Yes, 242 (15.6) No, 998 (64.5) Missing, 307 (19.9) |
Maximum tumour diameter, cm | Median, range, IQR | 1.5; 0.3–6.5; 1.0–2.0 |
Number of oligometastases at the time of emergence of the SBRT-targeted tumour | 1 | 1036 (67.0) |
2–5 | 503 (32.5) | |
Missing | 8 (0.5) | |
Lung lobe involved with treated tumour | Right upper lobe | 293 (18.9) |
Right middle lobe | 83 (5.4) | |
| Â | Right lower lobe | 321 (20.8) |
| Â | Left upper lobe | 294 (19.0) |
| Â | Left lower lobe | 226 (14.6) |
| Â | Unknown lobe | Right lung, 12; Left lung, 7 |
| Â | Missing | 311 (20.1) |
Beams | Multiple static | 1145 (74.0) |
| Â | Arc | 401 (25.9) |
| Â | Missing | 1 (0.1) |
X-ray energy | 4 MV only | 202 (13.1) |
| Â | 6 MV only | 1179 (76.2) |
| Â | Others | 160 (10.3) |
| Â | Missing | 6 (0.4) |
Field coplanarity | Coplanar field | 1139 (73.6) |
| Â | Non-coplanar field | 404 (26.1) |
| Â | Missing | 4 (0.3) |
Dose calculation algorithm | Type A | 541 (35.0) |
| Â | Type B | 799 (51.6) |
| Â | Type C | 144 (9.3) |
| Â | Missing | 63 (4.1) |
Dose prescription | IC | 1103 (71.3) |
| Â | D95 of PTV | 317 (20.5) |
| Â | Others | 127 (8.2) |
BED10 at isocenter, Gy | Median, range, IQR | 105.6; 75.0–289.5; 105.6–126.9 |
Number of SBRT fractions | 2–3 | 27 (1.7) |
| Â | 4 | 959 (62.0) |
| Â | 5 | 236 (15.3) |
|  | 6–16 | 324 (20.9) |
| Â | missing | 1 (0.1) |
OTT of SBRT, day | Median, range, IQR | 7; 3–81; 4–11 |