Table 2.
Patient and Tumor Characteristics
| Intraosseous Group | Extraosseous Group | |
|---|---|---|
| Patients | ||
| n (%) | 9 (43) | 12 (57) |
| Sex, n (%) | 3 Males (33) 6 Females (67) |
8 Males (67) 4 Females (33) |
| Age, y | 52.6 ± 9.6 | 58.1 ± 11.3 |
| Primary tumor site, n (%) | ||
| Breast | 6 (67) | 2 (17) |
| Liver | - | 4 (33) |
| Lung | 1 (11) | 3 (25) |
| Renal structures | 1 (11) | 2 (17) |
| Colorectal area | - | 1 (8) |
| Eccrine glands | 1 (11) | - |
| MRgHIFU treatment site, n (%) | ||
| Pelvis | 5 (56) | 8 (67) |
| Ribs | 2 (22) | 1 (8) |
| Humerus | 1 (11) | 1 (8) |
| Femur | 1 (11) | 1 (8) |
| Sacrum | - | 1 (8) |
| Prior EBRT to target metastasis, n (%) | 9 (100) | 12 (100) |
| 8 Gy 1# | 3 (33) | 2 (17) |
| 20 Gy 5# | 2 (22) | 1 (8) |
| 30 Gy 10# | 3 (33) | 1 (8) |
| High dose: >30 Gy or multiple treatments | 1 (11) | 8 (67) |
| Responder to prior EBRT? CR or PR | 3 (33) | 6 (50) |
| Baseline pain from target metastasis, n (%) | ||
| NRS 4–6 moderate pain | 3 (33) | 5 (42) |
| NRS 7–10 severe pain | 6 (67) | 7 (58) |
Note–Characteristics of patients (n = 21) treated with MRgHIFU, all of whom had previously received radiation therapy to the target tumor. Intraosseous lesions had intact bone cortex along the entire length of the tumor, with no visible periosteal involvement; extraosseous lesions had clear cortical breaches with visible periosteal involvement with tumor.
CR = complete response; EBRT = external beam radiation therapy; MRgHIFU = magnetic resonance-guided high-intensity focused ultrasound; NRS = numerical rating scale; PR = partial response; # = Fractions, ie, the number of treatment episodes over which the total EBRT dose was delivered.