Fibroid therapy stays on minimally invasive path

Hysterectomy and myomectomy still dominate the uterine fibroid treatment options. But specialists, including gynecologists, are gradually gravitating toward minimally invasive alternatives. The pace for change may quicken when definitive long-term outcomes on uterine artery embolization are published later this year.

Statistics from the National Uterine Fibroids Foundation in the U.S. show that nearly half of the 600,000 hysterectomies performed every year in the U.S. alone are prompted exclusively by uterine fibroids. About 12 women undergo a hysterectomy every 10 minutes, although nine of them may not even meet the American College of Obstetricians and Gynecologists' indications for the procedure.

Against this background, UAE's relative acceptance among clinicians and its growing popularity among patients do not seem surprising. Although hysterectomy or selective myomectomy constitutes the standard of care among gynecologists, many are beginning to accept UAE as an alternative.

"The data show that fibroid embolization works, that it is very useful, relatively safe, and effective," said Dr. W.J. Walker, a diagnostic and interventional radiologist at the Royal Surrey County Hospital in the U.K.

Walker and colleagues conducted more than 1000 UAE procedures for the Royal Surrey and London Clinic Trial. Their data, including more than five years' worth of follow-up, will be published later this year. More long-term outcomes from trans-Atlantic research institutions are also expected.

UAE'S LATEST HITS

A recent multicenter trial led by Dr. James B. Spies, chief of radiology at Georgetown University in Washington DC, compared UAE with hysterectomy in 152 women with symptomatic leiomyomas. The study found that patients undergoing UAE gained short- and midterm relief from symptoms and had relatively few complications after intervention. UAE patients spent on average less than one day in the hospital and 11 days away from work after embolization, compared with 2.3 and 33 days, respectively, for hysterectomy.

Patients showed a statistically significant reduction in bleeding at three- and six-month follow-up with UAE. Ninety-eight percent of hysterectomy patients showed pelvic pain improvement at one-year follow-up, compared with 84% of UAE patients. Although more patients expressed satisfaction with symptomatic improvements after hysterectomy, postprocedural complications were significantly less frequent among patients undergoing UAE (Obstet Gynecol Surv 2004;59[12]:819-820).

Refinement of the technique is leading to fresh approaches with new modalities. Conventional wisdom still favors ultrasound as the preferred screening modality for most benign uterine disorders, including fibroids.

But several studies reported at the 2004 RSNA meeting touted MR's utility in the diagnosis and management of fibroids. In a study enrolling 19 patients, Dr. Reena Jha and colleagues at Georgetown found that high-resolution MR angiography could detect ovarian collateral arteries prior to UAE, with implications for patient management.

Another team led by Dr. Jean-Pierre Pelage, an associate professor of radiology at the Hopital Lariboisiere in Paris, found that fibroid perfusion measured 24 hours after embolization was a good predictor of clinical response to treatment. In this study, 73% of women undergoing gadolinium-enhanced pelvic MR imaging one day after UAE showed complete devascularization of all fibroids. MRI also helped investigators confirm that long-term improvement depends largely on fibroid infarction and not shrinkage.

THE NEWCOMER

MR-guided focused ultrasound ablation, also known as focused ultrasound surgery, represents the latest breakthrough in uterine fibroid treatment. Although ultrasound's thermal properties have been known since the early 20th century, only within the last several years has the technology been used to ablate tumors. Initial results obtained by a multicenter team of researchers from the U.K., Germany, Israel, and the U.S. showed that a concentrated beam of ultrasound energy could effectively reduce fibroids' volume and alleviate symptoms (AJR 2004;183[6]:1713-1719).

Despite early successes, experts agree that it is too soon to determine the therapeutic worth of focused ultrasound, much less place it in head to head competition with UAE. Some researchers believe the two techniques represent distinct treatment alternatives for different types of patients.

Focused ultrasound seems to work best for individual fibroids, whereas embolization can treat multiple tumors with one procedure. Though minimally invasive in relation to hysterectomy or myomectomy, UAE still requires sedation and overnight hospitalization. Focused ultrasound is an outpatient procedure with relatively few complications that allows patients to go back to work in two days or less. So far, researchers agree that focused ultrasound is a brand-new technology with great potential that looks straightforward and easy to use, said Dr. Clare Tempany, director of clinical MRI at Brigham and Women's Hospital.

"We will have to learn over the next couple of years where it fits in a large population of women with fibroids," she said.

A study presented at the 2004 RSNA meeting by Tempany and colleagues included 31 patients with fibroids and found that performing focused ultrasound ablation during the proliferative phase of the menstrual cycle yielded better results. The researchers divided patients into two groups to undergo focused ultrasound during the proliferative (group A) and secretory (group B) phases. Ninety-four percent of patients in group A showed symptom improvement six months after treatment, versus 33% in group B.

Finding out how focused ultrasound compares with UAE in terms of cost-effectiveness could be a difficult undertaking. While some researchers estimate that focused ultrasound and UAE may end up costing about the same, without proper cost analyses, reimbursement levels, and-above all-randomized controlled trials comparing these techniques, nothing is certain.

"We have been trying to get funding from the National Institutes of Health to run a randomized controlled trial comparing focused ultrasound and UAE. We have not succeeded," Tempany said.

PREGNANCY AND PROTOCOLS

Despite unexpectedly promising findings on women's ability to remain fertile after UAE, most researchers consider the results marginal at best. The literature worldwide registers only about 50 cases. Myomectomy represents the only research-validated alternative for women who want fibroids treated without compromising their ability to become pregnant.

"The cohorts that have been investigated so far have not been young cohorts who are interested in fertility. Doing a randomized controlled trial with embolization versus myomectomy would answer key questions for women and physicians," said Gaylene Pron, Ph.D., an assistant professor of epidemiology at the University of Toronto.

Defining turf also remains an issue. Whatever interdisciplinary cooperation exists seems to be concentrated on one side of the Atlantic: Data from at least four European countries show pioneering UAE programs started with full-fledged collaboration between gynecologists and radiologists.

Far from replicating that trend, interdisciplinary relationships relating to UAE in North America have been characterized more by suspicion. An article published in August 2004 by The Wall Street Journal suggested that ob/gyns were consciously refusing to mention UAE to patients out of financial self-interest. In the face of the accusations-all the more startling considering that a gynecologist is credited with the development of the procedure-the ACOG issued a rebuttal stating that, contrary to what the WSJ article indicated, the college has not only analyzed and disseminated information about UAE among patients, but has actively supported UAE research.

The roles of interventional radiologists and gynecologists are evolving. Whether the model of care will be gynecologist-led or interventionalist-led, some definition of who is responsible for what is needed well in advance. Pron and others look to the standards outlined by the U.K.'s National Institute for Clinical Excellence.

No matter what the long-term data on UAE eventually show, researchers agree that more studies are needed to know its real effectiveness compared with hysterectomy and myomectomy. Studies that include different subsets of patients, especially those more directly affected by fibroids, are also needed. Until definitive data become available, names such as US Secretary of State Condoleezza Rice may offer a reminder that the condition is highly prevalent among black women. An ongoing study of fibroids in black women may provide more information on that aspect of the condition.