A phase III clinical trial has shown that noninvasive magnetic resonance-guided focused ultrasound treatment that heats the cancer within the bone, relieves pain and improves function for most patients when other treatment options are limited. The results were published recently in the Journal of the National Cancer Institute (JNCI).1
Magnetic resonance–guided focused ultrasound surgery (MRgFUS) is a technique that’s been safely used to treat thousands of women with uterine fibroids. However, “this is the first phase III study to use this technology in the treatment of cancer,” says the study’s principal investigator and lead author Mark Hurwitz, MD, Vice Chairman of Quality, Safety and Performance Excellence and Director of Thermal Oncology in the Department of Radiation Oncology at Thomas Jefferson University.
Although radiation therapy is commonly used to treat bone-related pain and effective for most patients, not all patients experience pain relief and over time those who do may have recurrence of pain. In cases where radiation therapy is not an option, alternative treatments are required.
Study Design
A total of 147 patients from 17 centers in the United States, Canada, Israel, Italy, and Russia were enrolled in the study and randomized to undergo MRgFUS or a sham treatment. Patients in the treatment group received focused ultrasound precisely targeted to their bone tumors to heat the tumor tissue to between 65 and 85 degrees Celsius, resulting in its destruction. During each treatment, the patients were monitored real-time via magnetic resonance imaging to ensure the right tissue was targeted and the right temperatures were reached while ensuring heat in surrounding normal tissues and organs remained at safe levels. The control group underwent the same procedure but without the ultrasound device turned on. Finally, patients who did not respond to the placebo treatment within 2 weeks were allowed to be unblinded and offered MRgFUS.
According to the study authors, patients responded well to treatment, with 64% experiencing either no pain or a significant reduction in their pain at 3 months as measured by a two point or greater decrease in the numeric rating score for pain, a clinically validated measurement tool. Many patients were able to reduce or stop use of opioid medications. Most patients experienced pain relief and improved functioning within several days of treatment.
Outpatient, Noninvasive Procedure
“It’s clear that for many of these patients, pain has a major impact on their everyday lives,” says Dr. Hurwitz. “This approach offers a new way to help alleviate that pain via an out-patient noninvasive procedure.”
The next steps in this line of research, said Dr. Hurwitz, is to refine the treatment technique to get an even greater response rate, and to apply radiation and thermal therapy together in treatment of bone metastases noting the established clinical benefits for other malignant conditions with this combination. ■
Disclosure: This study was supported by InSightec Ltd, Tirat Carmel, Israel. Dr. Hurwitz has provided expert testimony on behalf of Insightec for the purpose of regulatory approval.
Reference
1. Hurwitz MD, Ghanouni P, Kanaev SV et al: Magnetic resonance-guided focused ultrasound for patients with painful bone metastases: Phase III trial results,” J Natl Cancer Inst. April 23, 2014 (early
release online).
