Researchers at Harvard-affiliated Brigham and Women’s Hospital (BWH) have demonstrated that focused ultrasound, a novel, nonsurgical approach to the treatment of uterine fibroids, appears to be safe. The advent of this treatment, which can be performed as a day procedure, presents a dramatic alternative to current invasive methods such as hysterectomy, the most common cure for fibroids. The study findings are outlined in the July issue of The American Journal of Obstetrics and Gynecology.
“Annually, about 200,000 hysterectomies are the result of uterine fibroids,” said Elizabeth Stewart, clinical director, BWH Center for Uterine Fibroids, and assistant professor of obstetrics, gynecology, and reproductive biology at the Medical School. “A hysterectomy is by no means a perfect solution to the problem. As women are seeking minimally invasive alternatives, we are encouraged by these results.”
It is estimated that about a quarter of all women suffer from uterine fibroids, noncancerous tumors that develop in the muscle layer of the uterus. The swelling associated with fibroids often causes a woman’s uterus to expand to a size equivalent to a four- or five- month pregnancy. As a result, they can lead to abnormal bleeding and pelvic pain, and may contribute to a variety of reproductive problems such as infertility, recurrent miscarriage, and premature labor.
Combining the powers of magnetic resonance imaging (MRI) and ultrasound, this new approach allows physicians to first map out the exact location of the fibroid and then target a thermal beam at the tumor. The process involves eliminating the fibroid with high temperatures that heat the mass, cut off its blood supply, and then shrink it. With the aid of real-time MR imaging, doctors can ensure that the correct amount of heat is delivered to the fibroid under direct visualization, preventing harm to surrounding tissue and outer layers of the skin.
“We found that, overall, women tolerated this treatment extremely well,” said Stewart. “All women who underwent the procedure were treated as outpatients and only one required continued observation. Additionally, no patients were seen for complaints between the treatment and follow-up period, and most encouraging, 75 percent rated pain as mild.”
A total of 55 women, ranging in age from 38 to 55, were treated. Patients underwent multiple sonications – meaning the ultrasound beam was actively heating and ablating the tumor – for about two hours, during which a small area of the fibroid was targeted. Upon discharge, pain and discomfort were self-reported. Overall, the women recorded discomfort as low, and only 10 percent indicated they used pain medication after treatment.
“Our data also showed that focused ultrasound can be accurately and safely delivered under MR guidance into the target tissue,” said Clare Tempany, director of BWH’s Clinical MRI and Focused Ultrasound Program, who also published a feasibility profile with Stewart in the journal Radiology in March 2003. “This is encouraging as our objective is to treat the optimal amount of tissue in the shortest time possible.”
When considering the patient experience, focused ultrasound may offer advantages compared with current therapies, said Stewart and Tempany, associate professor of radiology at the Medical School. Even the least invasive treatment, uterine artery embolization, may cause post-procedure pain and fever. For patients undergoing hysterectomy and myomectomy, the most popular surgeries, there are risks associated with anesthesia, along with incision pain and morbidity. Finally, for all current treatments, recovery time is substantial and the rate of recurrence can be as high as 20 percent.
“MRI-guided focused ultrasound, the first completely noninvasive therapy for fibroids, appears to provide targeted results with an excellent safety profile,” said Stewart. “Our next step will be to research how we can fully optimize this technology for the benefit of patients.”
The research was funded by the National Institutes of Health and InSightec-TxSonics, Haifa, Israel.