Table 1 –
Patient and treatment characteristics (n = 20 patients)
| Frequency | Percentage | |
|---|---|---|
| Median age (interquartile range) | 60.5 (55.5–64.75) | |
| Gender | ||
| Female | 4 | 20 |
| Male | 16 | 80 |
| Ethnicity | ||
| Hispanic | 3 | 15 |
| Non-Hispanic | 17 | 85 |
| Race | ||
| White | 15 | 75 |
| Asian | 1 | 5 |
| Black | 2 | 10 |
| Missing | 2 | 10 |
| IMDC risk score at enrollment | ||
| 0, favorable | 5 | 25 |
| 1–2, intermediate | 15 | 75 |
| Mean primary tumor diameter at initial diagnosis ± std. dev. | 7.7 ± 2.4 | |
| Histology | ||
| ccRCC | 18 | 90 |
| Papillary | 1 | 5 |
| RCC, NOS | 1 | 5 |
| Fuhrman grade | ||
| 2 | 7 | 35 |
| 3 | 7 | 35 |
| 4 | 6 | 30 |
| Nephrectomy | ||
| Cytoreductive | 12 | 60 |
| Localized/locoregional RCC | 7 | 35 |
| None | 1 | 5 |
| Initial staging (AJCC) | ||
| pT1 | 2 | 10 |
| pT2 | 1 | 5 |
| pT3 | 14 | 70 |
| pT4 | 2 | 10 |
| pTx | 1 | 5 |
| cN | ||
| cN1 | 2 | 10 |
| cNx | 8 | 40 |
| M | ||
| cM1 | 11 | 55 |
| Number of lines of systemic therapy prior to SAbR | ||
| 1 | 4 | 20 |
| 2 | 10 | 50 |
| 3 | 4 | 20 |
| 4 | 2 | 10 |
| Type of systemic therapy at SAbR | ||
| TKI | 8 | 40 |
| ICI | 8 | 40 |
| ICI + TKI | 3 | 15 |
| mTOR-I + TKI | 1 | 5 |
| Number of mets at SAbR | ||
| ≤5 | 8 | 40 |
| ≥6 | 12 | 60 |
| Synchronous metastasis | ||
| No | 8 | 40 |
| Yes | 12 | 60 |
| Number of SAbR sites treated initially | ||
| 1 | 11 | 55 |
| 2 | 9 | 45 |
| Size of SAbR lesions treated initially (cm), median (interquartile range) | 3.4 (2.4–4.9) | |
| All sites treated with SAbR (n = 37) | ||
| Kidney | 3 | 8.1 |
| Bone, nonspine | 6 | 16.2 |
| Spine | 5 | 13.5 |
| Lung | 10 | 27 |
| Liver | 6 | 16.2 |
| Adrenal | 3 | 8.1 |
| Abdomen | 2 | 5.4 |
| Soft tissue | 1 | 2.7 |
| Brain | 1 | 2.7 |
| SAbR fractionation (n = 37) | ||
| 1 fraction | 6 | 16.2 |
| 3 fractions | 21 | 56.8 |
| 5 fractions | 10 | 27 |
| Median/mode dose (range) | ||
| 1 fraction | 22/25 | (15–25) |
| 3 fractions | 36/36 | (36–45) |
| 5 fractions | 40/40 | (35–40) |
AJCC = American Joint Committee on Cancer Staging, eighth edition; ccRCC = clear cell renal cell carcinoma; ICI = immune checkpoint inhibitor; IMDC = International Metastatic RCC Database Consortium; mets = metastases; NOS = not otherwise specified; RCC = renal cell carcinoma; SAbR = stereotactic ablative radiotherapy; std. dev. = standard deviation; TKI = tyrosine kinase inhibitor.