Fibroids are smooth muscle tumours, medically known as leiomyomas. They are almost always benign. They start off in the muscle wall of the womb (intramural fibroids) and can push inwards (submucous) or outwards (subserosal)
» Submucosal – distorts the uterine cavity
» Intramural – no distortion with <50% protruding into serosal surface
» Subserosal – sessile or pedunculated, with >50% protrudes out of serosal surface
Unfortunately, no causative factors have been identified, except that fibroids grow in the presence of oestrogen hormone, hence usually seen in the reproductive age group. This is why fibroids tend to shrink in women when they reach menopause.
Fibroids are extremely common, with as many as 1 in 2 women diagnosed with the condition on ultrasound scan. There are racial differences, with fibroids being even more common in women of Afro- Caribbean or Asian origin.
Some women don’t know they have fibroids, as they often cause no symptoms. They may be picked up on an incidental Xray/CT or MRI scan or if an abdominal or pelvic ultrasound scan is being performed for some other reason.
However, a significant number of women will suffer from heavy and/or painful periods (Secondary Dysmenorrhoea) or irregular bleeding. Women may have intermenstrual bleeding( in between periods) or rarely bleeding after intercourse (post coital bleeding), as a result of fibroids. Women may present with a pelvic mass, that they may notice themselves or may be causing urinary or bowel pressure symptoms, Fibroids are rarely the sole cause of infertility or recurrent miscarriage (<10% of cases). The anatomical location is important, with submucous fibroids causing the most problem. Also if the fibroid is more than 5 cm or near the cervix or near the tubal ostia, it can pose a problem. Painful periods that have a new onset may need further investigations. Other causes of pain could be from discomfort from size of fibroid, pain from twisting of a pedunculated fibroid, pressure symptoms, red degeneration, usually in pregnancy. Coexisting endometriosis/adenomyosis is another reason for pain with fibroids. Very rarely, sarcomatous cancerous change and rapid growth of a fibroid can cause pain and needs urgent investigation.
Fibroids may be diagnosed sometimes in pregnancy (1-4% of pregnancies on ultrasound) The vast majority (80%) of women have no adverse effects at all from the fibroids in pregnancy with usually no significant change. Only a small proportion of women have miscarriage, preterm labour, red degeneration, placental abruption, fetal growth restriction, and bleeding as a result of fibroids. Usually there are other reasons. Fibroids are almost never removed in pregnancy and most pregnancies have a successful outcome.
Fibroids are almost always benign growths. Very rarely do fibroids turn cancerous. Rapid growth with pain may indicate sarcomatous (cancerous) change. In such a situation, urgent referral will be recommended to a cancer specialist.
Usually a blood test (FBC) to check iron levels and for anaemia and a pelvic ultrasound scan is all that is needed to diagnose symptomatic fibroids. Further scans such as an MRI scan and other investigations will depend on presenting symptoms and location of fibroids. Other factors such as age, fertility wishes and patient choice will dictate management. It is important to assess the patient properly with a detailed reproductive history, thorough examination and appropriate investigations. After a thorough workup of infertility/recurrent miscarriage/pain/period problems, a Hysteroscopy/Laparoscopy/HSG(hysterosalpingogram to check tubal patency) may be recommended to assess the fibroids. Careful assessment and explanation of the benefits and risks of any treatment including any surgical procedure must be carried out before offering the right procedure to the patient.
Some women with small fibroids may be helped with oral medications such as NSAIDs like mefanamic acid. These prostaglandin synthetase inhibitors help reduce menstrual blood loss by as much as 20-50%. The tablets may also help with headache, nausea and pain. Other drugs such as inhibitors of fibrinolysis (Transexamic acid) can reduce menstrual blood loss by 50%. Drugs may have some side effects and varied results in different patients. Your doctor will prescribe the correct drug for you after discussion. Synthetic progestogens (Provera, NET) or the combined oral contraceptive pill may be helpful in some situations. Injections such as GnRH analogues are best-used short term, around an operation to avoid unwanted side effects. The non-contraceptive use of the MIRENA IUS releases a low dose of progesterone hormone daily and can help reduce periods very significantly in a number of women with fibroids. It also provides very effective contraception.
Fibroids within the cavity can cause heavy, painful periods, irregular bleeding, infertility and recurrent miscarriage. After appropriate investigations, most of these fibroids can be removed in a simple 1-2 stage procedure, through the vaginal route, under a short anaesthetic as a day case procedure (Transcervical Resection of submucous Fibroids - TCRF). Women often notice a dramatic difference in their periods. Higher pregnancy rates and livebirth rates have been noted if the fibroid resected is between 2cm and 5cm in size. For women who have completed their family and have heavy periods, not responding to simple methods, an Endometrial Ablation can be carried out at the same time. A Mirena IUS can be fitted in some patients at the same time.
Removal of other fibroids (Myomectomy) is usually reserved for women wishing to maintain fertility, as surgery is often risky and complicated. This can be done by either an open operation or through keyhole surgery. This procedure will be offered to you after thorough discussion of all options appropriate to the situation. Risks and benefits will be discussed in detail.
In women who have completed their family and with large fibroids, especially if other treatments have failed or are not acceptable, a hysterectomy may be the right option. Most hysterectomies will be performed through the keyhole (laparoscopic Hysterectomy), although some women can have a vaginal procedure while for others an open abdominal approach may be needed, based on the individual situation. Sometimes a hormone injection may be used before surgery to improve iron levels and to shrink the fibroids (GnRh analogues). Risks and benefits of surgery versus other techniques such as fibroid embolisation will be discussed in detail before any decision is finalised.
Fibroid embolisation (Uterine Artery Embolisation - UAE) and ultrasound treatment (Magnetic Resonance Guided Focused Ultrasound - MRgFUS) to fibroids are newer techniques that hold promise for women who wish to avoid surgery in certain situations or for whom surgery is not suitable (e.g. women with fibroids in positions close to important structures or those with multiple fibroids have a higher surgical risk).
Patients with failed open, hysteroscopic or laparoscopic myomectomies may be offered UAE or MRgFUS. Patients with large submucous fibroids or numerous interstitial and/or submucous fibroids where myomectomy would be technically difficult or with a high recurrence rate may benefit from UAE or MRgFUS.
Careful evaluation is needed before suggesting UAE to women who wish to retain fertility.
UAE involves an assessment by a radiologist after arranging an MRI scan to assess suitability for shrinking the fibroids by cutting off the blood supply using small particles through a little cut in the groin, allowing access to the blood vessels. The risks and benefits will be discussed thoroughly before the procedure.
MRgFUS allows safe non invasive ultrasound treatment under the guidance of MRI imaging, shrinking fibroids over time. This is relatively new and available only in a few places in the UK. Risks and benefits and a thorough assessment will take place before recommending this procedure.
Not all women are suitable for fibroid embolisation or for ultrasound treatment and a decision as to which of the treatment methods is suitable will be made with the help of your gynaecologist. Risks and benefits of each procedure will be discussed in detail with you, before a decision is taken. Complementary therapies have not shown to be of any proven benefit for treatment of fibroids.
Nitu Bajekal, June 2010