Table 1.
Characteristics of the training, validation and test datasets
| Training set | Validation set | Test set I | |
|---|---|---|---|
| Number | 133 | 204 | 21 |
| Mean age (range) years | 69 (35–89) | 71 (42–91) | 71 (53–101) |
| Male (%) | 82 (61.7) | 126 (61.7) | 10 (47.6) |
| Stage I (%) | 24 (18) | 33 (16.2) | 4 (19) |
| Stage II (%) | 34 (25.6) | 37 (18.1) | 4 (19) |
| Stage III (%) | 75 (56.4) | 134 (65.7) | 13 (61.9) |
| Histology: SCC (%) | 69 (51.9) | 95 (46.7) | 14 (66.7) |
| Histology: adeno(%) | 41 (30.8) | 77 (37.7) | 5 (23.8) |
| Histology: NSCLC NOS (%) | 18 (13.5) | 25 (12.3) | 2 (9.5) |
| Histology: other (%) | 5 (3.8) | 7 (3.4) | 0 |
| SUVmean (range) | 8.25 (1.78–17.4) | 8.44 (2.11–23.7) | 7.75 (4.44–16.8) |
| SUVmax (range) | 16.5 (4.9–42.8) | 15.9 (3.26–49.5) | 13.6 (6.66–39.2) |
| SUVpeak (range) | 14.2 (3.8–35.4) | 14.2 (2.9–43.1) | 12.5 (6.26–34) |
| MTV (range) mls | 40.4 (5.13–467) | 33.7 (5.27–525) | 30.8 (7.03–230) |
| TLG (range) | 344 (16.2–5.45 × 103) | 315.2 (19.4–5.7 × 103) | 266 (40.5–2.59 × 103) |
| Median overall survival (months) | 25 (0–83) | 21.0 (0–85) | 20 (2–37) |
| Number of deaths (%) | 88 (66.2) | 145 (71.1) | 17 (81%) |
| Length of follow-up (median + IQR in months) | 26 (12–39) | 22.0 (11–36) | 21 (8–31) |
SCC squamous cell carcinoma, Adeno adenocarcinoma, NSCLC non-small-cell lung cancer (not otherwise specified, i.e., not classified into squamous or adenocarcinoma), MTV metabolic tumour volume, TLG total lesion glycolysis, IQR interquartile range. Stage AJCC/UICC 7