Fibroids are the most common benign tumor in women and can be solitary or multiple, ranging in size from a few millimeters to 30 cm or larger. about 70% of white women aged 50 years and about 80% of black women have this condition.
The risk factors for uterine fibroids are as follows:
(1) Ethnicity: Black women and Asian women have a higher incidence than white women, and multiple fibroids are more common.
(2) Genetics: If a first-degree relative has uterine fibroids, the risk of occurrence is increased.
(3) Age: Incidence increases with age in women of childbearing age.
(4) Early menarche (age <11 years).
(5) Pregnancy: The incidence of uterine fibroids is lower in full-term pregnancies and more common in women who have not given birth.
(6) Hormonal contraception: single progesterone injectable contraceptives, oral contraceptives reduce the risk of uterine fibroids.
(7) Obesity: weight gain and centripetal obesity increase the risk of fibroids.
Symptomatic fibroids often require surgical treatment, which imposes a considerable financial burden on health care services.
1. What is uterine fibroids? Where are they often found?
Uterine fibroids are composed of smooth muscle cells and fibroblasts, round, hard in texture, with swirling or woven structures visible on the cut surface and densely arranged. The pathophysiology of uterine fibroids is currently unknown. Current theories suggest that fibroids arise from mutations in a single smooth muscle cell.
The uterus is the most common site of uterine fibroids. The location of the fibroids may have some impact on symptoms and the patient’s quality of life. For example, submucosal fibroids may cause problems such as severe menstrual bleeding and infertility. Large fibroids may occupy more sites and may expand from the endometrial cavity to the surface of the uterine plasma membrane.
2.How to control the growth of fibroids?
Estrogen and progesterone control proliferation and maintain fibroids. Most drug treatments work by inhibiting the production of sex hormones and suppressing their action. Hormone replacement therapy may lead to the growth of fibroids, but the clinical significance of this is not yet certain.
3.What are the clinical characteristics of uterine fibroids?
The occurrence of uterine fibroids in premenarcheal girls and postmenopausal women is relatively rare. A retrospective study showed that fibroids increase in size by about 35% per year, and that small fibroids (less than 2 cm) or intermural fibroids grow more rapidly.
4. What are the clinical manifestations of fibroids?
Uterine fibroids are usually asymptomatic. When symptoms do occur, they are typical and include severe menstrual bleeding, pelvic pain, secondary dysmenorrhea, abdominal distention, pressure symptoms, urinary problems (such as frequent urination, urinary urgency and hydronephrosis), non-specific bowel symptoms and infertility, which can have a negative impact on quality of life. This condition often requires treatment. The size of the fibroid may not be the determining factor for symptoms.
5.When do I need to be checked?
Uterine fibroids are very common and are often diagnosed incidentally due to the widespread use of high resolution ultrasound.
Primary care requires a gynecologic history evaluation for patients presenting with symptoms, including cervical screening, and should include a pelvic exam to determine the presence of a mass, a hemoglobin evaluation to determine the presence of iron deficiency anemia, and a mid-stage urinalysis to rule out urinary tract infection if urinary symptoms are present. For patients who cannot be diagnosed, those with suspicious symptoms or clinical or imaging suspicion of malignancy require further investigations. Asymptomatic uterine fibroids
Patients with asymptomatic uterine fibroids, if the diagnosis can be confirmed, often do not require further investigation or treatment.
6.When is secondary treatment needed?
Patients with symptomatic fibroids who have had poor results from primary treatment need secondary treatment, and some patients may prefer uterine preservation therapy. Uterine fibroids do not usually cause irregular bleeding, and early referral is needed if such symptoms occur. Patients with fibroids presenting with infertility are advised to go to the local fertility clinic for primary investigation.
7.For the evaluation of fibroids, what kind of imaging is required?
If fibroids are suspected, an abdominal and pelvic examination followed by an ultrasound may be used. In most cases, the size, location and number of fibroids can be determined, and the relationship between fibroids and symptoms can be indicated. For example, fibroids pushing on the bladder may help explain urinary symptoms. Because the diagnosis of smooth muscle sarcoma relies on histologic examination, imaging (including ultrasonography) is not helpful in diagnosing smooth muscle sarcoma.
In some cases, where increased visualization of uterine fibroids is needed, magnetic resonance imaging (MRI) is required. However, similar to ultrasound, MRI cannot confirm the diagnosis of malignancy, and CT is of little help in the treatment of fibroids.
8.When do fibroids need to be treated and what treatment method should be chosen?
Treatment is only needed when fibroids are symptomatic. If fibroids (greater than 3 cm) cause severe menstrual bleeding and affect quality of life, hysterectomy, myomectomy or uterine artery embolization may be considered for treatment. The most important clinical factor in deciding on treatment is the need to preserve the uterus, the desire to have children, or both. This usually determines whether follow-up, medication, radiation therapy, hysterectomy or hysterectomy is preferred.
Hysterectomy is the ultimate solution for all symptoms of fibroids, but it is a permanent loss of fertility and is more harmful to the patient than other methods.
9.What kind of treatment can be considered for primary care?
For severe menstrual bleeding due to fibroids, standard medication may also be effective in reducing severe menstrual bleeding.
10. Which is the most effective drug treatment?
Medication for fibroids is symptomatic. Mefenamic acid and tranexamic acid may reduce severe menstrual bleeding and pain, and the drugs are safe and well-tolerated. Because these two drugs need to be taken only during menstruation, major adverse effects are very rare.
Hormonal therapy for severe menstrual bleeding includes oral contraceptives, oral norethindrone, and levonorgestrel intrauterine delayed-release systems. Although the above studies on the efficacy of hormone therapy excluded women with small fibroids, progesterone and estrogen can promote the growth of fibroids. Selective progesterone receptor modulators now offer another option for the pharmacological treatment of uterine fibroids. Multiple randomized controlled trials have shown that these drugs reduce blood loss and shrink fibroids. Ulipristal acetate has recently been approved for short-term (3 months) preoperative use or long-term intermittent use (≥ 12 months), which may avoid surgery.
Gonadotropin-releasing hormone agonists are more well-established treatments that can be used for primary treatment, although they are often started at the time of secondary treatment to relieve uterine fibroid symptoms. These agonists are effective as long as the treatment continues, and symptoms often recur after stopping treatment.
11.What kind of therapy will be used for secondary treatment?
(1) Interventional treatment
Uterine artery embolization aims to block the blood supply to the uterus, resulting in local ischemia of the fibroids, although the myometrium can receive a new blood supply through collateral circulation (ovarian and vaginal). It is an effective and safe treatment for uterine fibroids. Major complications of uterine artery embolization are rare, but mild complications (e.g., nausea, pain, vaginal discharge) are more common than surgery. Re-interventions are often required within 5 years.
The impact of uterine artery embolization on infertility and pregnancy outcomes is unknown.
(2) Surgical treatment
Surgical treatment of uterine fibroids is either the removal of fibroid tissue alone (myomectomy) or the removal of the uterus and fibroids (hysterectomy). Both methods can be accomplished through hysteroscopic surgery or laparoscopic surgery, with open surgery often performed for large fibroids. The advantage of myomectomy over hysterectomy is that fertility can be preserved and hysterectomy can be avoided.
① Myomectomy
Myomectomy removes fibroid tissue, but preserves the uterus. Although the incidence of intraoperative bleeding requiring blood transfusion is as high as 30%, the need for emergency hysterectomy is rare and this possibility needs to be mentioned in the informed consent form. A systematic review of surgical treatment of fibroids suggests that evidence suggests that myomectomy (whether open, laparoscopic or hysteroscopic) is not effective in improving infertility or pregnancy outcomes.
Fibroid removal for larger fibroids requires an open procedure. However, some submucosal fibroids (often <5 cm in diameter) can be removed hysteroscopically; although some observational studies have suggested improvement in severe menstrual bleeding, few studies have reported on the effectiveness of this procedure in treating severe menstrual bleeding. It is not possible to conclude whether hysteroscopic removal of fibroids improves the chances of pregnancy in infertile patients.
②Hysterectomy
Hysterectomy is the most effective and permanent solution to the symptoms associated with fibroids. The mortality rate of hysterectomy is approximately 0.6 to 1.6 per 1,000, and no studies have compared the incidence of complications between hysterectomy and myomectomy.
12. What is the relationship between fibroids and infertility?
The exact relationship between uterine fibroids and infertility is not known. Some evidence suggests that submucosal fibroids cause infertility; the effect of intermural fibroids is uncertain. Subplasmaline fibroids do not appear to have an effect. Observational studies support myomectomy for submucosal fibroids. The relationship between intermural fibroids and infertility is uncertain, but the current consensus does not believe that removal of intermural fibroids improves infertility.
13. What happens to fibroids during pregnancy?
U.S. data suggest that approximately 18% of African-Americans and 8% of European-Americans have fibroids detected at early pregnancy screening, although it is not known when these fibroids appear. A systematic review showed that although most fibroids are asymptomatic and the rate of spontaneous abortion is significantly higher in women with fibroids, no significant difference was found in the rate of preterm birth.
However, older age at childbirth increases the risk of fibroids and miscarriage. Uterine fibroids close to the placenta are likely to be associated with early pregnancy bleeding and miscarriage. Severe pain during pregnancy, such as fibroid “redness” (an increase in the size of fibroids over the blood supply, causing local anemia) or bleeding is uncommon, but specialist consultation is recommended. Uterine fibroids in pregnancy do not require treatment only if there are acute complications.
14. Is there a risk of transformation into a malignant tumor?
Smooth muscle sarcomas are rare malignant tumors that are difficult to distinguish clinically from uterine fibroids. Uterine smooth muscle sarcoma can only be diagnosed by histopathological examination. In a recent meta-analysis, the probability of finding a smooth muscle sarcoma in a postoperative histological examination of a patient with what was thought to be a benign fibroid was 2.94 per 1,000. the risk increases with age.
Rapid growth of fibroids, especially after menopause or with gonadotropin-releasing hormone agonists, is often a cause for concern and expert consultation is recommended.