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Management of Uterine Fibroids
By Millie A. Behera, M.D.and Phyllis Leppert, MD, PhD©
Duke Department of Obstetrics and Gynecology
www.dukehealth.org
Duke Fertility Center
5704 Fayetteville Road
Durham, NC 27713
(919) 572-HOPE or 4673
Uterine fibroids, also known as leiomyomas or myomas, are the most common gynecologic
tumor in women of reproductive age, affecting approximately 30 to 40 percent of premenopausal
females. The prevalence increases with age, with an estimated 70 to 80 percent of women
developing fibroids by age 50.(1)
While typically classified as benign, uterine fibroids can cause troublesome symptoms to
approximately 30 percent of affected women, including heavy vaginal bleeding, pelvic pressure,
pain, obstructive urinary and bowel symptoms, as well as reproductive difficulties.(1,2) Fibroids are
one of the most common indications for hysterectomy in the U.S., accounting for approximately
200,000 cases per year. Fibroid-related morbidity has a significant economic impact on health
care: the cost of health care for women with fibroids is more than double that of women without
this condition, and annual costs related to the diagnosis of fibroids are over $2 billion.(3)
Fortunately, new approaches to managing uterine fibroids are improving the outlook. Minimally
invasive and non-invasive treatments such as MRgFUS (MRI-guided focused ultrasound) - a
novel therapy recently introduced f at Duke - are providing effective treatment for fibroids while
offering faster recovery and fewer complications than hysterectomy.(4) At the same time, new
studies have increased our understanding of the biology of uterine fibroids and created inroads for
developing more effective medical therapies.
What Causes Uterine Fibroids, and Who Is at Risk?
While the exact etiology of fibroids is still unclear, physician-scientists at the Duke Center for
Uterine Fibroid Biology and Therapy have co-authored several of the most recent studies
examining the underlying disease process that leads to the formation of uterine fibroids.(5,6,7) These
studies indicate that fibroids grow by accumulation of collagen and components of the
extracellular matrix. This fibrosis is similar to that observed in the formation of keloid scars. The
Center, which includes physician investigators, basic scientists, and epidemiologists, is currently
involved in several studies to elucidate the molecular biology of uterine fibroid growth and
etiology for associated bleeding and subfertility.
Factors implicated in the development of fibroids include genetic, hormonal, and growth factors,
especially transforming growth factor beta (TGFb)-related cellular changes.(8,9) Clinical risk factors
associated with fibroids include obesity, hypertension, nulliparity (having no biological children),
family history, and race. Up to 70 percent of African American women have uterine fibroids, and
these generally tend to be larger, more numerous, and produce more severe symptoms.(1)
How Are Uterine Fibroids Best Diagnosed?
Given the fact that uterine fibroids are highly prevalent in childbearing women and are associated
with decreased fertility, prompt and accurate diagnosis is important. Uterine fibroids are most
often diagnosed by ultrasound as part of the evaluation for associated symptoms or when an
enlarged uterus is found on physical examination. However, other imaging modalities such as
saline infusion sonograpy (3-D) and MRI may provide more accurate diagnosis and better
delineation of fibroid size and location.
Fibroids are classified based on location within the uterine wall: subserosal, intramural, and
submucosal. These definitions are often used to determine appropriate interventions and/or
surgical approach.
What Are Current Treatment Approaches - And What Therapies Are on the
Horizon?
Current treatment options for uterine fibroids run the gamut from medical intervention to noninvasive
and minimally invasive therapies to hysterectomy. Several factors must be addressed in
determining the appropriate treatment for each individual, including size and location of fibroids,
severity of symptoms, and desire to retain fertility or uterine preservation.
Medical options. Current medical options for fibroid management are limited. Of the established
interventions, GnRh agonists are the most effective. GnRHa have been used to control bleeding
and pressure-related symptoms by reducing fibroid size and decreasing bleeding. Within three to
six months, fibroid size is reduced by approximately 30 to 50 percent. However, these effects are
short- lived; fibroids grow and symptoms recur soon after treatment is discontinued. Furthermore,
due to hypoestrogenic effects, treatment time is limited to six months, after which bone density
can be affected. Add-back hormone therapy can be used to combat this effect, but some studies
have found that this regimen may decrease the treatment efficacy. Hence GnRh agonists have
been found to be most useful as an adjunct to surgical treatment of fibroids, since preoperative
use results in improvement in hematocrit levels and less blood loss during surgery.(10)
Table 1 - Medical therapy for fibroids (10–16)
| DRUG CLASS |
MECHANISM |
EFFECTS |
CONSIDERATIONS |
| GnRH agonists |
Suppression of ovarian steroidogenesis
production - delayed
pituitary
downregulation |
Fibroid size and
symptom reduction up
to 50% within 3-6
months |
Hypoestrogenic side
effects: hot flashes,
vaginal dryness,
headaches. Prolonged
use associated with
reduced bone mineral
density |
| GnRH antagonists |
Suppression of ovarian
steroidogenesis
production - immediate
pituitary
down regulation |
Reduction in fibroid
size 25-40% and
symptom improvement
within 3 weeks |
Hypoestrogenic side
effects: hot flashes,
vaginal dryness,
headaches. Prolonged
use associated with
reduced bone mineral
density |
| Oral contraceptives |
Endometrialstabilization, variable
effects on leiomyomas |
May improve uterinebleeding, but no
significant decrease in
fibroid size |
Use judiciously - both estrogen and
progesterone may
promote fibroid growth
(increased mitotic
activity) |
| Progestin only |
Endometrial
stabilization/atrophy,
variable effects on
leiomyomas |
Mixed results - both
fibroid shrinkage and
enlargement have been
shown; may induce
amenorrhea |
Use judiciously -
progesterone may
promote fibroid growth
(increased mitotic
activity) |
| Androgens |
Combination hormonal
and vascular effects
(androgenic,
progestogenic,
antiprogestogenic, and
antiestrogenic actions) |
24% fibroid size
reduction in 4 months,
may improve bleeding
symptoms |
Side effects: weight
gain, edema, acne, oily
skin, hirsutism, voice
changes, headaches,
hot flashes, altered
libido, decreased
breast size, and muscle
cramps |
| Aromatase inhibitors* |
Reduces estrogen
synthesis and effects |
Fibroid size reduced
60-70% within 1-2
months in case report |
Hypoestrogenic side
effects; further studies
needed |
| Antiprogestins* |
Anti-progesterone
effect - reduces action
and number of
progesterone receptors
in fibroids and
myometrium |
Improved symptoms in
60-75%, may induce
amenorrhea, reduction
in fibroid volume 25-
50% within 3 months |
Side effects include
hot flashes, elevated
hepatic enzymes, and
endometrial
hyperplasia |
Mixed progesterone
receptor
antagonist/agonists* |
Local progesteronemediated
effects on
leiomyomas and
endometrium |
Decreased menstrual
bleeding (up to 80%)
and fibroid size
reduction up to 36%
within 12 wks, may
induce amenorrhea |
Maintains follicular
phase estrogen levels,
no adverse endometrial
effects - causes
nonphysiologic
secretory changes
(clinical elevance
unknown) |
Mixed estrogen
receptor
antagonist/agonists* |
Estrogen antagonist
effects on fibroid and
endometrium |
Inconsistent results -
trend to decreased
fibroid size in small
heterogeneous studies |
Side effects: leg
cramps, hot flashes.
Increased risk of
thromboembolic
events |
| Antifibrotics* |
Interfere with growth
factors, leiomyoma
cell proliferation and
extracellular matrix/
collagen production |
Interfere with fibroid
growth |
Long-term effects not
known, further studies
needed |
*Investigational medical therapies
Several other hormone-related medical treatments have been used to treat uterine fibroids;
however, most of these medications are still being evaluated in clinical trials and are considered
investigational.11 Some of these proposed interventions are aimed at controlling fibroid growth
and related symptoms by targeting ovarian steroid production. These include combined birth
control pills, progestin-only preparations, androgens, both estrogen and progesterone receptor
antagonists, and mixed receptor antagonist/agonists. Other medications, such as antifibrotic
agents, target growth factors and affect extracellular matrix production and angiogenesis within
the fibroid. These medical treatments are summarized in Table 1. The Duke Center for Uterine
Fibroid Biology and Therapy is actively investigating new drug therapies to treat uterine fibroids,
and we expect this to be an area of significant advancement and progress over the next several
years.
Non-medical options. Since most medical options are investigational and not recommended as
first-line, long-term treatment for symptomatic fibroids at this time, the most common treatments
remain either conservative surgical intervention or definitive surgery. Until now, the most
prevalent treatments have been hysterectomy (surgical removal of the uterus) and myomectomy
(surgical removal of individual fibroids). However, more women are looking for options that
provide minimal intervention and shorter recovery time.
Minimally invasive surgical treatments can provide excellent results when patient and fibroid
characteristics are appropriate. In general, such treatments are best suited for women with a few,
discrete symptomatic fibroids, while extensive fibroids are best treated with more definitive
approaches. Minimally invasive approaches include laparoscopic and hysteroscopic
myomectomy, as well as uterine artery embolization, a radiologic procedure that has also become
more popular over the last several years.
Table 2. non-medical treatment interventions - conservative and definitive (4, 17-19)
TREATMENT |
MECHANISM |
EFFECTS |
CONSIDERATIONS |
Uterine artery
embolization |
Ischemic necrosis |
Fibroid size reduction
40-60% within 4
months, menorrhagia
improvement up to
85% |
Post-procedure pain,
risk of major adverse
events (such as serious
infectious
complications)1-2%,
may be associated with
adverse pregnancy
outcomes, ovarian
failure in 1-2% |
| MRI-guided focused
ultrasound |
Localized thermal
necrosis |
Symptomatic
improvement up to
71% within 3 months,
fibroid size reduction
up to 30% - increased
in proportion to treated
fibroid volume,
treatment effects
sustained up to 24 months with low rates
of secondary or repeat
procedures |
Patient selection
criteria and fibroid
characteristics
important - posttreatment
volume
determines
efficiency/duration of
clinical results;
minimal risk of adverse events (skin
burn, nerve injury) |
| Myolysis
(Laparoscopic) |
Thermal necrosis |
Fibroid shrinkage up to
70% by 12 months |
Surgical risks,
significant
postoperative
adhesions |
Laparoscopic
myomectomy |
Excision |
Removal of large
fibroids, high patient
satisfaction with
symptomatic
improvement |
Surgical risks; often
requires cesarean
delivery with future
pregnancy - labor is
not advised, due to
small risk of uterine
rupture |
| Abdominal
myomectomy |
Excision |
Removal of all
palpable fibroids, high
patient satisfaction
with symptomatic
improvement |
Surgical risks; often
requires cesarean
delivery with future
pregnancy - labor is
not advised, due to
small risk of uterine
rupture |
| Hysterectomy |
Excision |
Definitive treatment -
high patient
satisfaction rate with
symptomatic
improvement |
Surgical risks |
A recent addition to the treatment toolkit is MRI-guided focused ultrasound (MRgFUS), in which
precisely pinpointed, high-intensity ultrasound waves are used to “burn away” fibroids without
harming normal surrounding tissues. This cutting-edge technology, which offers women the
option of same-day, non-surgical treatment, is available at Duke through the Duke MRI-Guided
Focused Ultrasound Treatment Program. With increasing availability of conservative treatment
choices, both patients and their physicians have the opportunity to individualize therapy based on
the goals of each patient. More details on the pros and cons of various nonmedical therapies are in Table 2.
Phyllis C. Leppert, MD, PhD, is a professor and vice chair for research in the Duke Department
of Obstetrics and Gynecology, and also director of the new Duke Center for Uterine Fibroid
Biology and Therapy. Millie Behera, MD, is an assistant professor in the Department of
Obstetrics and Gynecology, clinical director of the Duke Center for Uterine Fibroid Biology and
Therapy, and director of the Duke MRI Guided Focused Ultrasound Treatment Program.
1 Day Baird D, Dunson DB, Hill MC, Cousins D, Schectman JM. High cumulative incidence of
uterine leiomyoma in black and white women: ultrasound evidence. Am J Obstet Gynecol. 2003
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2 Buttram VC Jr, Reiter RC. Uterine leiomyomata: etiology, symptomatology, and management.
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3 Hartmann KE, Birnbaum H, Ben-Hamadi R, Wu EQ, Farrell MH, Spalding J, Stang P. Annual
costs associated with diagnosis of uterine leiomyomata. Obstet Gynecol. 2006 Oct;108(4):930 -7
4 Stewart EA, Gostout B, Rabinovici J, Kim HS, Regan L, Tempany CM. Sustained relief of
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5 Behera M, Feng L, Yonish B, Catherino W, Leppert PC. Thrombospondin-1 (TSP-1 and
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6 Catherino WH, Leppert PC, Stenmark MH, Payson M, Potlog-Nahari C, Nieman LK, Segars J.
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10 Lethaby A, Vollenhoven B, Sowter M. Efficacy of pre-operative gonadotrophin hormone
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12 Lingxia X, Taixiang W, Xiaoyan C. Selective estrogen receptor modulators (SERMs) for
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13 Chwalisz K, Larsen L, Mattia-Goldberg C, Edmonds A, Elger W, Winkel CA. A randomized,
controlled trial of asoprisnil, a novel selective progesterone receptor modulator, in women with
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14 Maruo T, Ohara N, Wang J, Matsuo H. Sex steroidal regulation of uterine leiomyoma growth
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15 Shozu M, Murakami K, Inoue M. Aromatase and leiomyoma of the uterus. Semin Reprod Med.
2004 Feb;22(1):55 - 60
16 Shozu M, Murakami K, Segawa T, Kasai T, Inoue M. Successful treatment of a symptomatic
uterine leiomyoma in a perimenopausal woman with a nonsteroidal aromatase inhibitor. Fertil
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17 The REST Investigators. Uterine-artery embolization versus surgery for symptomatic uterine
fibroids. N Engl J Med. 2007 Jan25;356(4):360 - 70
18 Marshburn PB, Matthews ML, Hurst BS. Uterine artery embolization as a treatment option for
uterine myomas. Obstet Gynecol Clin North Am. 2006 Mar;33(1):125 - 44
19 Sharp HT. Assessment of new technology in the treatment of idiopathic menorrhagia and
uterine leiomyomata. Obstet Gynecol. 2006 Oct;108(4):990 - 1003
©Millie Behera M.D. and Phyllis Leppert, MD, PhD
Duke Department of Obstetrics and Gynecology
www.dukehealth.org
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