Gynaecologic Problems: Fibroids

Description

Uterine leiomyomas , commonly known as fibroids , are well-circumscribed, non-cancerous tumours arising from the myometrium (smooth muscle layer) of the uterus. In addition to smooth muscle, leiomyomas are also composed of extracellular matrix (i.e., collagen, proteoglycan, fibronectin).
Other names for these tumours include fibromyomas , fibromas , myofibromas , and myomas .
Leiomyomas are the most common solid pelvic tumour in women, causing symptoms in approximately 25% of reproductive age women. However, with careful pathologic inspection of the uterus, the overall prevalence of leiomyomas increases to over 80%, because leiomyomas can be present but not symptomatic in many women. The average affected uterus has 6-7 fibroids.

Leiomyomas are usually detected in women in their 30's and 40's and will shrink after menopause in the absence of post-menopausal oestrogen replacement therapy. They are 2-5 times more prevalent in black women than white women.

Symptoms and Signs

Research indicates that between 20% and 50% of women have fibroid-related symptoms. The 2 most common symptoms of fibroids are abnormal uterine bleeding and pelvic pressure:

• The most common bleeding abnormality is menorrhagia . Normal menstrual periods typically last 4-5 days, whereas women with fibroids often have periods lasting longer than 7 days.
• Pelvic pressure results from an increase in size of the uterus or from a particular fibroid. Most women with leiomyomas have an enlarged uterus. It is not unusual for a uterus with leiomyomas to reach the size of a 4-5 month pregnancy. In addition to vague feelings of pressure because a fibroid uterus is usually irregularly shaped, women can experience pressure on specific adjacent pelvic structures including the bowel and/or bladder. Pressure on these structures can result in difficulty with bowel movements and constipation or urinary frequency and incontinence.
• Leiomyomas are also associated with a range of reproductive dysfunction including recurrent miscarriage , infertility , premature labour , foetal malpresentations, and complications of labour .

Diagnosis and Treatment

The diagnosis of leiomyomas is usually easily determined by a bimanual pelvic examination . In addition, imaging studies such as ultrasonography , MRI (magnetic resonance imagery), and CT (computed tomography) may be useful in confirming the diagnosis. In patients experiencing menorrhagia or recurrent pregnancy losses, assessment of the uterine cavity is important because the presence of a submucous fibroid can be missed on traditional ultrasound. Hysterosalpingography , sonohysterography, and hysteroscopy may be used in these cases. More invasive procedures such as laparoscopy can also aid in definitive diagnosis.

In general, fibroids only need to be treated if they are causing symptoms. The primary treatment for patients with large or symptomatic fibroids is surgery .
Hysterectomy (surgical removal of the entire uterus) is the most frequent operative technique used to treat this disorder. In fact, fibroids are the most common indication for hysterectomy, accounting for approximately 1/3 of hysterectomies.
When women wish to preserve childbearing potential, a myomectomy may be performed. Unlike hysterectomy in which the entire uterus is removed, myomectomy is a surgical procedure in which individual fibroid(s) are removed. Unfortunately, there is a significant risk of recurrence of fibroids after myomectomy.
There are also several innovative techniques being studied as possible surgical treatment for fibroid-related bleeding. Myolysis involves delivering electric current via needles to a fibroid at the time of laparoscopy. Cryomyolysis involves using a freezing probe in a similar manner. Uterine artery embolisation is a radiological alternative to surgery that involves placing a catheter into an artery in the leg and guiding the catheter via x-ray pictures to the arteries of the uterus. Once there, the catheter is used to deliver agents that block off these major blood vessels. While all of these treatments may prove to be effective treatments for fibroids, compared to more traditional options, the number of patients treated by these methods have been small, the follow-up relatively short term, and the safety of these procedures in women desiring pregnancy has not been demonstrated.

Medicines can also help control fibroid-related symptoms. The most effective medications for the treatment of fibroids are gonadotropin releasing hormone agonists (GnRHa), which induce a low-oestrogen (menopause-like) state. Because fibroids are dependent on oestrogen for their development and growth, induction of a low oestrogen state causes reduction of tumour and uterus mass, resolving pressure symptoms. Unfortunately, cessation of GnRH agonist treatment is followed by a rapid regrowth of the fibroids and of the uterus to pre-treatment volume. Additionally, because bone also requires oestrogen, long term use of GnRH agonists can significantly decrease bone density and can lead to bone loss or osteoporosis. Currently, therefore, use of GnRH agonists alone for treatment of fibroids is usually limited to a short 1-3 month preoperative course to shrink the uterus to facilitate a surgical procedure or to induce amenorrhoea to improve haematological condition before surgery.

The information in this page is presented in summarised form and has been taken from the following source(s):
1. Center for Uterine Fibroids: http://www.fibroids.net/