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This is one hot topic that deserves all the coverage it is receiving lately. According to estimates, uterine fibroids affect more than 40 percent of all women over 40 at some point in their lives, often during pregnancy, one of the most critical points of their lives. In women of African descent, it could be as high as 50 percent. Uterine fibroids are benign tumors that arise from the muscular wall of the uterus and grow to significant size inside the uterus, producing a variety of painful symptoms. While their cause is a matter of debate, fibroids will often increase in size during pregnancy due to the elevated levels of estrogen in the system and often reduce greatly following menopause. They can range from the size of a pea to the size of a five-month-old fetus, putting pressure on other organs in the pelvis. While typically non-cancerous, uterine fibroids cause severe symptoms including uterine bleeding, pelvic pain and cramping and they may put pregnancies at risk. |
Accidental interventionalist
Historically, the first line of treatment for fibroids was surgery, typically a hysterectomy to remove the entire uterus or a myomectomy, the surgical removal of fibroids while leaving the uterus in tact, if possible. The recovery times for both procedures are extensive (six to 12 weeks) and both bring the usual pain and risks of surgery.
In the late 1980s, French gynecologist Jacques Ravina started to embolize the uterine arteries in women who experienced excessive uterine bleeding following fibroid surgery. According to information on the University of Indiana Medical School Web site ( http://www.indyrad.iupui.edu/public/
interventionalradiology/uterine_fibroid_embo ), Ravina later began to embolize the uterine arteries pre-operatively, in an effort to reduce the bleeding during the surgical management of fibroids. The results of those pre-operative procedures stunned Ravina – the patients were experiencing drastic decreases in symptoms and surgeries were being cancelled.
And from that, a new treatment option was born: uterine fibroid embolization, or UFE. In the United States, the procedure was pioneered at UCLA Medical Center (Los Angeles) and today there are interventional radiologists performing it across the country. According to the Society of Cardiovascular and Interventional Radiology (SCVIR of Fairfax, Va.), UFE is the fastest growing interventional specialty, growing at almost 40 percent per quarter. At the recent SCVIR meeting in San Diego in March, there were more than 20 presentations focused on UFE’s outcomes.
Once fibroids are clearly diagnosed and identified, a catheter is introduced in the femoral artery and guided into the uterine arteries that provide blood flow to the fibroids. The catheter is then used to release tiny bubbles filled with an embolic agent (most often polyvinyl alcohol) which embolize the uterine arteries and cut off the blood flow to the fibroids. Without blood, the fibroids eventually shrink and symptoms are greatly decreased. Most doctors performing the procedure say there is a very minimal risk of fibroids recurring or new fibroids growing.
Most interventional radiologists performing the procedure report patients experiencing some pain directly following the procedure, described as a “crampy” pain which is caused by the lack of oxygen in the affected tissue. Typically that pain recedes within 10 to 24 hours and recovery is swift from that point on. According to statistics from SCVIR, “significant post-embolization syndrome” occurs in 15 percent of patients which may cause fever, nausea and vomiting. It typically abates within three days.
“The amount of pain the patients have after the procedure is significant,” says Carlos Forcade, M.D., an interventional radiologist with The Fibroid Embolization Center at the NYUnited Hospital Medical Center (Port Chester, NY). Forcade says some patients have even likened the pain to being kicked by a horse. Forcade usually offers an epidural and Toradol for the pain, which maintains good pain relief for six hours.
But the amount of post-procedure pain varies greatly depending on the patient. Some interventional radiologists report patients feeling well and leaving the hospital only 12 hours after the surgery.
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Fluoroscopic image of a uterine artery before a UFE procedure (left), and after UFE procedure (right). |
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“Maybe it’s because I’m a female and I have periods from hell and can relate to the concept of cramps and pain,” jokes Linda Hughes, M.D., an interventional radiologist at the Miami Cardiovascular Institute (Miami). “But, knock on wood, I’ve had good luck with the post-procedure pain. I know some [physicians performing the procedure] have anesthesia involved and use PCA pumps and go as far as to use epidurals, but I have not had to do any of that. We load the patients up with a non-steroidal anti-inflammatory the night before and the morning of the procedure and then we use a routine conscious sedation during the procedure.”
Following the procedure, Hughes may provide a patient with Morphine or Percocet if requested. She usually gives the patient a prescription for Percocet to take home, but says few need it. She insists that patients continue to take anti-inflammatory agents for a week following the procedure regardless of how they feel.
Imaging pre-procedure – MRI vs. ultrasound
The growth of the UFE procedure is closely tied to imaging techniques and technologies. In the diagnostic stage, ultrasound and MRI are used to determine the exact size and location of the fibroids before the arteries are embolized. The debate seems to lie in which modality is the right choice. Typically, a transabdominal ultrasound is performed and often a transvaginal ultrasound as well to confirm the volume of the uterus.
“It’s my opinion that ultrasound is adequate,” says Hughes. “Between the transabdominal and the transvaginal, you get a good look at the pelvis in terms of looking for adnexal structures and other masses and getting a feel for the size of the uterus.”
Philadelphia’s Robert L. Worthington-Kirsch, M.D., concurs with Hughes. Kirsch, a clinical assistant professor of radiology at the Philadelphia College of Osteopathic Medicine (Philadelphia), also feels ultrasound is adequate for the diagnosis and placement of fibroids and less than 10 percent of his patients are given an MRI prior to the UFE procedure.
“Ultrasound is inexpensive, it’s fast and patients tolerate it well,” Kirsch said. “I don’t think that MRI routinely before a uterine artery embolization is clinically necessary, and I don’t think it’s justifiable on a cost basis. It’s less convenient for the patient. So I use MRI just for answering questions. If I have questions about the patient’s diagnosis, then I use an MRI.”
The Numbers GameFollowing are some statistics on uterine fibroid embolization: ???? BioSphere Medical Inc. estimates that fibroids affect 25 million women in the United States alone, and each year 5.5 million seek treatment. ???? According to SCVIR, UFE is more than 84 percent effective in reducing bleeding and more than 88 percent effective in alleviating pain associated with uterine fibroids. ???? SCVIR reports 4,165 UFE procedures have been performed in the United States as of September 1999 with no deaths and 25 complications resulting in additional surgery within 30 days of the procedure. The facilities performing these procedures average 375 procedures per month. ???? The UCLA School of Medicine pioneered UFE in the U.S., and according to the UCLA Web site, 40 percent of women older than 40 have fibroids. ???? After UFE, UCLA researchers report: ???? According to the Fibroid Embolization Center at the NYUnited Hospital Medical Center (Port Chester, N.Y.), roughly 50 percent of women of African background develop fibroids. Cancer occurs in a fibroid perhaps once in every 750 to 1,000 cases. |
But MRI certainly has its share of supporters in imaging fibroids prior to UFE. James Spies, M.D., is a strong supporter of MRI’s use in diagnosing fibroids. Spies is the chief of interventional radiology and associate professor at Georgetown University Medical Center (Washington, D.C.), one of the first centers in the country to begin performing UFE. Spies says MRI is generally agreed to be the most accurate means of distinguishing fibroids from adenomyosis, a condition where endometrial cells invade the muscular wall of the uterus itself, enlarging the uterus and causing similar symptoms as fibroids.
“That’s important because we don’t know if the outcome of embolization on adenomyosis would be as good as it is for fibroids,” Spies explains.
Another strong proponent of MRI is Nilesh H. Patel, M.D., assistant professor in the radiology department at Indiana University School of Medicine (Indianapolis).
“MRI gives you an excellent evaluation of the location of the fibroids,” Patel says. “Whether they are in the uterine cavity, the muscle itself or on a stalk and hanging freely off the uterine wall.”
Cost is always an issue when comparing MRI and ultrasound examinations, but Spies feels that Georgetown has gotten over that hurdle by implementing a limited protocol for the exam.
“The whole protocol takes about 20 to 25 minutes, so we felt justified in charging less,” Spies adds. “There’s no law that says you have to charge X amount for a certain procedure.”
Imaging during the procedure
During the embolization procedure itself, fluoroscopy is used to guide the catheter up the femoral artery and into the uterine arteries to administer the embolic agent. According to John Kuo, M.D., director of vascular and interventional radiology at Boca Raton Community Hospital (Boca Raton, Fla.), the radiation exposure during a typical UFE procedure is similar to that of a barium enema. Radiation time typically is 10 to 15 minutes during a UFE procedure, Kuo says.
Forcade says he tries to keep embolizations under 45 minutes and fluoro time within six to nine minutes.
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Ultrasound image of uterus before UFE procedure (left), and after UFE procedure (right). |
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Follow-up
The recommendations for surgical follow-up vary, but usually an ultrasound or MRI exam (whichever was performed pre-procedure) is performed at three months or six months after the procedure to measure the shrinkage of the tumors.
“Most of the results in the literature show there is really little change until six months,” says Patel.
Hughes emphasizes that the end goal of UFE is not a certain shrinkage of the fibroids, but abatement of the symptoms.
“With the first couple of women I had done, I was almost afraid to do my follow-up consult with them because I was thinking, ‘I got the ultrasound and the fibroids are not any smaller – these patients are going to want to shoot me.’ Then I walked in and right away got hugs and patients saying, ‘I’m a new person’ and crying and everything.”
To date, the procedure has not been shown to affect future pregnancies, but it is an area that is being studied extensively. According to a statement from SCVIR, research presented at its annual meeting showed that “the ovarian functions of younger women does not appear to be affected by the procedure. Several of the more than 20 studies on the procedures being presented at the SCVIR meeting include patients who have become pregnant.” There have been cases of menopause onset following the procedure in 1 to 2 percent of cases, but it’s not known if this is procedure related or not. According to Spies, SCVIR is developing a large registry to determine the sub-group of women who can become pregnant and are trying to become pregnant.
Most doctors performing the procedure caution that UFE is not guaranteed, but to date, the risk of recurrence has been shown to be minimal. However, the procedure is typically performed on women who are close to menopausal age when fibroids will stop growing.
The Name GameThe term “UFE” is often used interchangeably with “UAE” to define uterine artery embolization. According to SCVIR, uterine fibroid embolization (UFE) is defined as “an embolization procedure of uterine arteries to shrink painful, enlarged, benign tumors in the uterus.” However, uterine artery embolization (UAE) is defined as “an embolization procedure of uterine arteries to stop life-threatening postpartum bleeding, potentially preventing hysterectomy.” Fibroids also are called by other names, such as: myoma, leiomyoma, leiomyomata and fibromyoma. According to the Fibroid Embolization Center at the NYUnited Hospital Medical Center, the different types of fibroids include:
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Tiny bubbles
In addition to the imaging equipment, a vital technology in UFE is the embolic agent used in the procedure. Currently, the two embolic agents being used are gel foam and polyvinyl alcohol (PVA). The primary difference between the two is that PVA is a permanent agent which does not leave the body, while gel foam will be absorbed by the body. Kuo said that despite the fact that PVA will remain in the arterial beds, there has been no evidence to show that it has any side effects after 20 years of use in embolizations in other regions of the body.
On the commercial front, BioSphere Medical Inc. (Marlboro, Mass.) is seeking FDA clearance for a new embolic agent, Embosphere Microspheres. The Microspheres differ from PVA in that they are all of similar size and shape, while PVA particles tend to be different shapes and sizes.
The advantage to the BioSphere product is that, unlike PVA, all of its particles are spherical and of similar shape and size. Spies, one of the researchers testing the product, says the spherical nature of the particles should make them less likely to clump up during embolization.
“I think that for patients that are embolized with PVA according to current protocols, there is a period of global uterine ischemia for a couple hours,” Kirsch explains. “With the Embosphere, we may be doing a more targeted embolization and we may have less global uterine ischemia than with PVA.”
A bright future
The results are virtually unanimous: the UFE technique has proven to be a very successful alternative to surgical options. Approximately 33 percent of all hysterectomies are performed to remove growing fibroids, according to information on the University of Indiana Web site. At least 25 percent of women undergoing myomectomy (surgical removal of fibroids) will require another surgical procedure to remove new fibroids, generally, a hysterectomy.
According to a survey of SCVIR members, as of September 1999, there had been 4,165 uterine artery embolization procedures performed in the United States. Of those 4,165, only 25 required a follow-up surgery 30 days after the procedure.
“That’s less than 1 percent,” Forcade says. “That’s an incredible number. That’s 4,165 women who were slated for hysterectomy, 3,140 of whom didn’t have the surgery because of this procedure.”
And what does the future hold for imaging and the treatment of uterine fibroids? In early April, the University of Mississippi Medical Center (Jackson, Miss.) reported completion of the first “I-MRI fibroid cryosurgery” in which Patrick Sewell, M.D., assistant professor of radiology, used an interventional MRI system to guide a CryoHit freezing probe from Galil Medical Ltd. (Tel Aviv, Israel) into a fibroid and freeze the cells of the tumor, killing them. More research is being planned into this area, but the 48-year-old patient was reportedly recovering well from the new procedure. 
