The objectives of this study were to evaluate the efficacy in pain management of magnetic resonance (MR)–guided focused ultrasound for the primary treatment of painful bone metastases and to assess its potential for local control of bone metastases.
This was a prospective, single-arm research study with approval from the institutional review board. Eighteen consecutive patients (female, 8; male, 10; mean [SD] age, 62.7 [11.5] years) with painful bone metastases were enrolled. The patients were examined clinically for pain severity and pain interference in accordance with the Brief Pain Inventory-Quality of Life criteria before and at each follow-up visit. Computed tomography and MR imaging were performed before and at 1 and 3 months after the magnetic resonance–guided focused ultrasound treatment. The nonperfused volume (NPV) was calculated to correlate the extension of the ablated pathological tissue in the responder and nonresponder patients.
No treatment-related adverse events were recorded during the study. The evaluation of pain palliation revealed a statistically significant difference between baseline and follow-up values for pain severity and pain interference (P = 0.001, both evaluations). In the evaluation of local tumor control, we observed increased bone density with restoration of cortical borders in 5 of the 18 patients (27.7%). In accordance with the MD Anderson criteria, complete and partial responses were obtained in 2 of the 18 patients (11.1%) and 4 of the 18 patients (22.2%), respectively. Nonperfused volume values ranged between 20% and 93%. Mean NPV values remained substantially stable after the treatment (P = 0.08). There was no difference in the NPV values between the responder and nonresponder patients (46.7% [24.2%] [25%–90%] versus 45% [24.9%] [20%–93%]; P = 0.7).
Magnetic resonance–guided focused ultrasound can be safely and effectively used as the primary treatment of pain palliation in patients with bone metastases and has a potential role in local tumor control.
From the Department of Radiology, Oncology and Anatomic Pathology, Policlinico Umberto I, Sapienza University of Rome, Viale Regina Elena, Rome, Italy.
Received for publication September 30, 2012; and accepted for publication, after revision, January 2, 2013.
Conflicts of interest and sources of funding: none declared.
Reprints: Alessandro Napoli, MD, PhD, Department of Radiology, Oncology and Anatomic Pathology, Policlinico Umberto I, Sapienza University of Rome, Viale Regina Elena, 324-00161 Rome, Italy. E-mail: email@example.com.