Table 1.
Patient demographics at initial SRS
| Variable | Category | All patients (N = 284) | Salvaged patients (N = 132) | Never salvaged patients (N = 152) |
|---|---|---|---|---|
| Sex | Male | 130 (46%) | 58 (44%) | 71 (47%) |
| Female | 154 (54%) | 74 (56%) | 81 (53%) | |
| Age at first SRS | Median | 61.6 | 59.7 | 63.5 |
| Histology | Non-small cell lung | 174 (61%) | 84 (64%) | 90 (59%) |
| Breast | 32 (12%) | 23 (17%) | 9 (6%) | |
| Melanoma | 20 (7%) | 8 (6%) | 12 (8%) | |
| Colon | 7 (2%) | 3 (2%) | 4 (3%) | |
| Other | 51 (18%) | 14 (11%) | 37 (24%) | |
| RPA class | 1 | 69 (25%) | 44 (33%) | 31 (20%) |
| 2 | 187 (66%) | 69 (52%) | 111 (73%) | |
| Unknown | 25 (9%) | 15 (11%) | 7 (5%) | |
| Number of lesions | Average | 3 | 3 | 2 |
| Range | 1-14 | 1-12 | 1-14 | |
| Maximum lesion size, cm3 | Average | 9.87 | 6.20 | 7.66 |
| Range | 0.1-93.29 | 0.27-93.29 | 0.27-64.45 | |
| Prescription dose (minimum dose delivered to largest met), Gy | Average | 18.63 | 18.37 | 18.91 |
| Range | 12-22 | 12-22 | 12-22 |
RPA, recursive partitioning analysis; SRS, stereotactic radiosurgery.