Infracting Uterine Fibroids: Embolization Provides Interventional Alternative to Hysterectomy
Of all the hot topics in the area of women's health, hysterectomy is certainly one of the most controversial. The most vehement critics of the procedure, which involves the surgical removal of the uterus, call it "female castration." Others describe it as one of the most unnecessary operations performed.
Critics of the procedure also point out that many women don't realize that less invasive-and certainly less traumatic-alternatives are available for certain gynecological conditions. According to a 1999 survey conducted by the Society for Women's Health Research, two-thirds of American women are unaware of alternatives to hysterectomy for treating excessive menstrual bleeding, or menorrhagia-a condition that can result from uterine fibroids. It is estimated that 600,000 hysterectomies are performed each year, and 20 percent of those are done to treat excessive bleeding, despite the existence of less invasive procedures. The survey also revealed that doctors recommend hysterectomy to one in four women and that 82 percent of those women accept their doctor's recommendation. Further, the survey indicated that more than one-third of women who had a hysterectomy didn't discuss potential alternatives with their doctor.
One of the alternatives available to women to treat menorrhagia-or, in fact, other symptoms stemming from fibroid tumors-is an interventional radiologic procedure called uterine fibroid embolization, also called uterine artery embolization.
"The success rate of this procedure of extremely high," points out Michael G. Wysoki, MD, clinical assistant professor of radiology, section of interventional radiology at Yale University School of Medicine in New Haven, Conn. "The technical success is 98 percent, and the clinical success-meaning that the women will not need any other intervention-is between 85 to 95 percent, depending on the symptoms. For bleeding, it is 95 percent."
Wysocki, a strong proponent of UFE, feels women owe it to themselves to explore the alternative. Hysterectomy, in many cases, is just too drastic, he feels.
"Hyterectomy involves three or four days of hospitalization and six weeks of recuperation," he says. "Also, there is the severe psychological and sexual implications with the procedure."
True, more women are asking about UFE. Still, far too few women opt for-or even know about-the procedure. "Less than five percent of all patients who could use this procedure are actually getting it," Wysoki reveals. "So far, only 10,000 UFEs have been performed. There is still a long way to go."
Interventional radiology (IR) began to blossom in the mid-1970s, thanks to the improved ability to see inside the body with radiologic imaging as well as the development of tools such as catheters. In recent years, IR has increasingly provided less invasive and less expensive alternatives to traditional surgeries. Procedures can be performed on an outpatient basis or require only a short hospital stay, as risk, pain and recovery time are minimized. In 1992, the American Medical Association recognized IR as a medical specialty. Today, more than 5,000 interventional radiologists practice in the United States.
Interventional radiologistsare physicians trained to do medical procedures employing radiology. They use X-rays, ultrasound and other imaging techniques to guide small instruments like catheters through bloods vessels. Common interventional radiologic procedures include angiography, balloon angioplasty, chemoembolization, and radiofrequency ablation. As Wysoki indicates, UFE is a far less common IR procedure. But he believes that that will change. "I have seen more and more gynecologists starting to embrace this procedure," he says. "It is becoming part of their arsenal for treating fibroids."
Uterine fibroid tumors-also called leiomyoma, leiomyomata, myoma or fibromyoma-are non-cancerous growths that develop in the muscular wall inside the uterus. The tumors are common and, in many case, not very problematical. However, for some women, the tumors cause heavy menstrual bleeding, an enlarged uterus, clotting, and pelvic pressure or pain. Often, these symptoms become so severe that women seek treatment.
Fibroids range in size from a quarter-of-an-inch to 10 inches or more. In severe cases, they can make a woman appear to be pregnant. The three primary types of tumors include suberosal fibroids, which develop under the outside covering of the uterus and expand outward through the wall; intramural fibroids, which develop inside the uterus lining and expand inward, increasing the size of the uterus; and submucosal fibroids, which develop just under the lining of the uterus. Submucosal fibroids are the least common but the most problematical. They can cause very heavy bleeding for prolonged periods.
Fibroids become more common as a woman gets older. The tumors appear in about 20 to 40 percent of women age 35 and older. Researchers aren't sure what causes the tumors, but they have been linked to genetic disposition. As many as 50 percent of African-American women have fibroids of a significant size.
The most common procedure used to treat fibroids has been a hysterectomy because it has proven to be especially effective. A less invasive alternative is myomectomy, a surgical procedure that removes just the fibroids and not the entire uterus. It is most often used in younger women who have not finished completing their families. Long-term studies have shown that it has an 80 percent success rate in controlling symptoms. However, the more fibroids present, the less successful the treatment. Plus, in 10 to 30 percent of cases, fibroids grow back in several years. Also, complications include infection and bleeding, and the procedure may cause pelvic scarring, which may make future surgery difficult and could lead to fertility problems.
While myomectomy, in the appropriate cases, is viewed as a desirable alternative to hysterectomy, many are starting to view UFE as an even better alternative. Results of studies have shown that 78 to 94 percent of women who undergo the procedure experience significant or total relief of pain and other symptoms. Also, regrowth of fibroids has not been a documented problem in the approximately 10,000 UFE procedures performed in the United States since 1996. The procedure has been successful even when multiple fibroids are involved. The expected average reduction in the volume of the fibroids is 50 percent after three months, with a reduction in the overall size of the uterus of about 40 percent.
Results of the first study that compared myomectomy with UFE were presented at the 26th Annual Scientific Scientific Meeting of the Society of Cardiovascular & Interventional Radiology (SCVIR) in March 2001. Conclusions indicated that UFE appears to be better than myomectomy in alleviating excessive menstrual bleeding resulting from fibroids.
The study, which was performed at Stanford University, showed that bleeding decreased significantly in more than 90 percent of women who had UFE compared with 61 percent of those who had myomectomy. Researchers also pointed out that because UFE is not a surgical procedure-and myomectomy is-recovery is typically five times faster and much less painful.
The study looked at 36 women had myomectomies and 76 women had UFE. After an average of nine months, 91 percent of UFE patients and 61 percent of myomectomy patients reported the heavy periods they had experienced due to fibroids had significantly improved. Also, 69 percent of UFE patients and 48 percent of myomectomy patients reported their pain significantly improved, and 73 percent of UFE patients and 95 percent of myomectomy patients reported pressure symptoms significantly improved.
According to the study, all UFE procedures were done as outpatient procedures. Myomectomy patients were hospitalized an average of three days. The UFE patients required narcotics for an average of three days to treat post-procedure pain. Myomectomy patients, on the other hand, required narcotics for an average of six days. UFE patients returned to normal activity after an average of six days, compared to 35 days for myomectomy patents. While blood loss related to the treatment was minimal with UFE, it averaged 380 ccs for myomectomy patients. Three of the women who had myomectomy required transfusions due to excessive blood loss.
The UFE procedure begins with the interventional radiologist making a small nick in the skin at the crease at the top of the leg. This allows access to the femoral artery.
"We then place a small catheter, which is about a millimeter in diameter, into the groin and we advance it into the arteries that supply blood to the uterus," explains Wysoki.
The interventional radiologist directs the catheter using fluoroscopy to a point where the artery divides into the multiple vessels supplying blood to the fibroids. Then the small particles called microspheres, which are about the size of a grain of sand, are inserted.
"Once that catheter is positioned in the uterine artery, and it is confirmed by dye injection, we block the uterine artery with these particles," says Robert Vogelzang, MD, chief of vascular and interventional radiology at Northwestern Memorial Hospital in Chicago.
During the procedure, an arteriogram provides the physician with a map of the blood supply to the uterus and fibroids. The microspheres become wedged in the vessels and slowly block the blood supply. "Once one artery is blocked, or embolized, we move to the other artery and do the same thing," says Vogelzang, "so the blood supply is blocked in both the right and left uterine arteries."
After the embolization, another arteriogram is performed to confirm the results. As a result of the restricted blood flow, the tumors begin to shrink.
"It is similar to what happens to them after menopause," says Wysoki. "They die due to a lack of blood supply, and then shrink and basically go away."
Vogelzang says that, following the procedure, most women can expect some post-operative pain and cramping for six to eight hours, and they will experience mild to moderate cramping for three to five days. Total recovery generally takes one to two weeks, but the full effects of the procedure take longer.
"The effects of the procedure may be immediate, but it may take up to one to three months to be fully effective," says Vogelzang.
Concerns and Complications
Early research suggests UFE may not adversely affect fertility in women younger than 45, although a small percentage of women 45 or older stop menstruating after the procedure. A number of women who have had the procedure have become pregnant. Long-term studies on the pregnancy rate after UFE have not been completed, however, and myomectomy is the standard-of-care for women desiring to become pregnant after fibroid treatment.
Vogelzang, however, feels that both myomectomy and UFE can have an affect on fertility by blocking tubes and/or causing ovarian failure. He says that is something that women should consider. "My feeling is that we don't know everything yet about the affect of this on fertility," he says, "and I am reluctant to recommend it for women who haven't completed their families or made a final decision about their fertility."
Though it is considered to be very safe, UFE does involve some risks, though complications have occurred in fewer than three percent of patients. Malcom G. Munro, MD, a professor in the Department of Obstetrics & Gynecology at UCLA School of Medicine, and a practicing gynecologist who performs artery occluding procedures, says the risks can involve "nuisance" risks, which involve the cramping and pain, and well as loss-of-function risks and threat-to-life risks.
"There seems to be a little increased risk of premature menopause," Munro says, "but it is tough to be sure what the magnitude of that risk is. It probably relates to microspheres getting into the ovarian vessels in some way."
The most "sinister" risk, he says, involves problems related to infection. "That can be the source of the threat-to-life risks," he says. "The risk range of death seems to be about one in a thousand. That's only an estimate. It is not certain. That's the same threat-to-life risk that is related to hysterectomy."
Other complications can include injury to the uterus from decreased blood supply or infection. Injury to other pelvic organs is possible, but no cases have been reported. The chance of significant complications is less than one percent.
Some women fear that UFE will negatively affect their sex lives. However, two recent preliminary studies showed that women's sex lives remain intact and often improve after the procedure. These studies, conducted at Yale and Georgetown University, and presented at the SCVIR annual meeting last March, showed that, for the majority of patients, the frequency and strength of orgasm either didn't change or improved after UFE. However, researchers said results needs to be confirmed with a larger prospective trial.
A major concern right now is getting the word out. The problem, as many see it, is that some physicians may not be aware of the alternatives or trained to do them. Even though more gynecologists have been recommending the procedure, many more still don't know that much about it.
"I think that's true," says Vogelzang. "I think there's a lack of knowledge. We are still early in the technology, and there is some natural reluctance on the part of some physicians."
Wysoki agrees about the lack of knowledge. But he feels physicians will have to make bring themselves up to speed, so to speak, as more and more women are becoming aware of the alternative. "The physicians are going to have to include this procedure when they speak to their patients," says Wysoki, "because this is a procedure that the women now know about."
In the meantime, researchers are working on making an effective procedure even better. Wysoki reports that he recently spoke with some experts in the field at the 2001 RSNA meeting who have been working on embolic agents that could significantly reduce some of the pain or discomfort women experience with the UFE procedure.
"They're developing new embolic materials that can make it possible not occlude the whole uterine artery," he reveals. "They would only occlude the fibroids."
Wysoki explains that these particles-called embospheres-do not clump together like the microspheres currently used.
"Therefore, you can leave the main uterine artery open while maintaining blood supply to the uterus and only infacting the fibroids," he says. "It has not been proven yet, but the impression of most of the experts is that the pain will be significantly decreased."