Table 1.
Patient, lesion, treatment, and imaging characteristics
| Characteristic | Discovery cohort |
Validation cohort |
All patients |
|---|---|---|---|
| Median (range) or n (%) | Median (range) or n (%) | Median (range) or n (%) | |
| Patient/lesion | |||
| No. of patients | 83 | 60 | 143 |
| No. of lesions | 92 | 60 | 152 |
| Age at treatment end (y) | 76 (42-99) | 75 (47-91) | 76 (42-99) |
| Female | 44 (53) | 28 (47) | 72 (50) |
| KPS | 80 (50-100) | 80 (50-100) | 80 (50-100) |
| Histologic type | |||
| Adenocarcinoma | 50 (54) | 41 (68) | 90 (60) |
| Squamous cell | 29 (32) | 11 (18) | 40 (26) |
| Other | 13 (14) | 8 (14) | 21 (14) |
| T stage | |||
| T1 | 64 (70) | 38 (63) | 102 (67) |
| T2 | 26 (28) | 22 (37) | 48 (32) |
| T3 | 2 (2) | 0 (0) | 2 (1) |
| Treatment | |||
| Diagnosis to treatment (d, interquartile range) | 80 (50-119) | 63 (39-82) | 70 (44-108) |
| Total dose (Gy) | 50 (25-60) | 50 (25-60) | 50 (25-60) |
| Fractions | 4 (1-5) | 3 (1-8) | 4 (1-8) |
| BED | 113 (80-180) | 105 (80-151) | 109 (80-180) |
| GTV (mL)∗ | 8.6 (0.3-79.9) | 11.5 (0.7-150.5) | 9.4 (0.3-150.5) |
| PET/CT imaging | |||
| Days between scans (interquartile range) | 62 (34-99) | 53 (28-69) | 56 (30-86) |
| SUV (U) | |||
| Diagnosis/staging | 7.3 (0.9-23.4) | 6.2 (1.4-22.4) | 7.1 (0.9-23.4) |
| Simulation | 9.0 (0.7-33.1) | 6.8 (1.3-24.2) | 8.2 (0.7-33.1) |
| MTV (mL) | |||
| Diagnosis/staging | 3.0 (0.1-39.0) | 4.4 (0.3-57.3) | 3.7 (0.1-57.3) |
| Simulation | 5.1 (0.02-106.7) | 7.9 (0.2-125.7) | 5.9 (0.02-125.7) |
| SUVV (U/d)∗ | 0.02 (–0.44-0.34) | 0.01 (–1.28-0.32) | 0.02 (–1.28-0.34) |
| MTGR (mL/d) | 0.01 (–0.44-0.70) | 0.02 (–0.31-0.88) | 0.01 (–0.44-0.88) |
Abbreviations: BED = biologically effective dose; GTV = gross tumor volume; KPS = Karnofsky performance status; MTGR = metabolic tumor growth rate; MTV = metabolic tumor volume; PET/CT = positron emission tomography with computed tomography; SUV = standardized uptake value; SUVV = SUV velocity.
∗
P < .05 between discovery and validation cohorts.