Uterine fibroids are one of the most common tumors of the female reproductive organs and are benign tumors formed by the proliferation of smooth muscle tissue in the uterus, mostly in middle-aged women. Perhaps because of its commonness, it is not taken very seriously, and few reports delve into the etiology of their occurrence or try to explain how they produce symptoms. In many cases, physicians counsel patients to undergo hysterectomy for the purpose of complete treatment. In fact, 30% of all hysterectomy cases are for uterine fibroids as an indication for surgery. In Canada, hysterectomy is the most common and most performed non-obstetric procedure, with 57,506 operations in 1982 alone. Therefore, it is important that we should be aware of the characteristics and symptoms of uterine fibroids and recognize how to treat them.
[Etiology and occurrence].
Uterine fibroids are benign smooth muscle cell tumors. Individual uterine fibroids originate from a single mother cell. Most clinical data suggest that the development and growth of fibroids are related to estrogen in the body. In fact, although some patients with leiomyoma have high estrogen secretion, most of them have high estrogen activity in the tumor, and this high activity can cause the production of a large number of estrogen receptors in the tumor and alter the local enzyme activity. As the tumor increases in size, it migrates to the adjacent muscular layer and extrudes the muscular layer into a thick homogeneous layer, or pseudocapsule. The pseudocapsule forms a thick wall that wraps around the tumor. The wall seen on the cut surface is highly diagnostic. The structure of the capsule is actually important because the structure of the capsule forms a safe surgical layer. If the surgery is performed inside the capsule, damage to the adjacent structures will certainly not occur. When the blood vessels supplying the tumor extend into the center of the tumor, the blood supply will be reduced and will cause necrotic degeneration of the myxoma. Degeneration is considered to be a normal phenomenon, a mere change in the degree of development, and is not in itself an indication for surgical treatment. Degeneration occurs most often during pregnancy and can lead to an increase in the size of the tumor. In a few cases, the tumor develops so rapidly that the peripheral blood supply is far from adequate and acute degeneration may eventually occur. If necrosis invades the adjacent blood vessels and extravasation of blood into the tumor occurs, it is called “red metaplasia of pregnancy”.
Fibrosarcoma can be malignant from benign fibroids, but researchers tend to think that fibrosarcoma is a new growth in the wall of the uterus, and in 1815 surgical specimens, Button and Reiter found only 3 cases of smooth muscle sarcoma, a very small total. In this case, it is difficult to detect the degeneration of the sarcoma. The most common symptom of smooth muscle sarcoma is abnormal vaginal bleeding, and an uncommon symptom is the discovery of an enlarged pelvic mass.
[Classification
1. According to the site of myoma growth, the body of the uterus is divided into myomas, which account for the majority, and cervical myomas, which are very few. The ratio of the two is about 12:1.
2.According to the relationship between leiomyoma and myometrium.
(1) Interstitial leiomyoma: It is the most common leiomyoma, which is located between myometrium walls and surrounded by myometrium layer, accounting for about 60%~70% of the total.
(2) Subplasma leiomyosarcoma: the leiomyosarcoma grows towards the plasma surface and protrudes from the surface of the uterus and is covered by the uterine plasma layer, accounting for 20%-30% of the total. When the leiomyoma protrudes obviously and only one tip is connected with the plasma layer of uterus, it is called subplasma leiomyoma with tip, and this kind of leiomyoma is prone to tip torsion; if the tip is chronically torsioned and the blood supply is obstructed, the tip will become thinner and thinner and finally break completely, and the leiomyoma will get blood supply from the neighboring organs, large omentum, intestinal mesentery, etc., forming wandering smooth muscle tumor or parasitic smooth muscle tumor; when the leiomyoma protrudes between the two lobes of peritoneum of broad ligament, it is broad ligament leiomyoma. Ligamentous leiomyosarcoma.
(3) Submucosal leiomyoma: It is a fibroid that grows toward the uterine cavity and protrudes into the uterine cavity, and its surface is covered by the mucosal layer of the uterus, accounting for 10%-15% of the total. If the fibroids protrude to a large extent, they form a tip. Submucosal fibroids with a tip sometimes protrude from the ectocervix, which is called submucosal fibroid delivery.
3, according to the number of fibroids occurring is divided into single uterine fibroids and multiple uterine fibroids, in fact, fibroids often exist in more than one.
[Clinical manifestations
Fibroids rarely have diagnostic symptoms, in fact, few patients can detect its appearance, due to the size of fibroids cause women’s discomfort is not very common, most patients with fibroids are only found during gynecological screening or since they feel the abdominal mass. The clinical manifestations of leiomyosarcoma are related to the growth site, size and growth rate of leiomyosarcoma.
It is the most common symptom and the main symptom of submucosal leiomyoma, which manifests as excessive menstruation, prolonged menstruation and shortened cycle, mostly due to the increase of uterine volume and endometrial area caused by submucosal leiomyoma and intermucosal leiomyoma, which also hinders the uterine venous blood flow and interferes with the contraction of uterine wall, and submucosal leiomyoma is often prone to necrosis and infection, resulting in heavy bleeding and long bleeding time, sometimes The bleeding may be persistent, irregular or intermenstrual. In patients with excessive menstruation, prostaglandin levels are high, and current reports have found that fibroids respond to increased prostaglandins, so perhaps menstrual disorders with fibroids are due to abnormal prostaglandins.
2.Abdominal pain The leiomyoma itself usually does not cause abdominal pain, but acute abdominal pain may occur when the subplasmic leiomyoma with a tip is twisted; the larger submucosal leiomyoma may cause lower abdominal cramping pain during delivery; lower abdominal pain may occur when the leiomyoma compresses the pelvis; severe abdominal pain may occur when the leiomyoma degenerates.
3. Compression symptoms When located in the anterior wall of uterus or anterior lip of cervix, myoma may cause frequent urination, urgent urination, difficulty in urination and urinary retention; when located in the posterior wall or posterior lip of cervix, myoma may cause difficulty in defecation and constipation due to compression of rectum; when located in the broad ligament, myoma may cause hydronephrosis due to compression of ureter and edema of lower limbs due to compression of pelvic veins.
Submucosal leiomyoma as a foreign body affects the implantation of pregnant eggs; leiomyoma itself changes the morphology of the uterine cavity and affects the implantation of pregnant eggs; leiomyoma compressing the fallopian tube affects the uptake of egg cells and thus affects conception. However, the connection between fibroids and infertility is mostly incidental.
5.Increased vaginal discharge Infection of submucosal fibroids often increases vaginal discharge, and sometimes patients visit the doctor with bloody leucorrhea; larger interstitial fibroids increase vaginal discharge due to increased secretion of glands as the uterine area increases.
6.Anemia Due to excessive menstruation caused by myoma, anemia often develops secondary to myoma, which is manifested as general weakness, blurred vision and palpitation.
7.Abdominal manifestation For interstitial myxoma or subplasma myxoma located in the anterior wall, patients often feel that their abdomen is swollen, and sometimes a mass can be found in the abdomen.
8.Gynecological examination Submucosal leiomyosarcoma can be seen at the moment of delivery as a red, solid mass at the opening of the cervix, and the uterus can be normal in size or evenly enlarged; intermural or subplasma leiomyosarcoma can be palpated as irregular nodular protrusions on the surface of the uterus; tipped subplasma leiomyosarcoma can be seen as a solid mass in the pelvis, which is closely related to the uterus; cervical leiomyosarcoma can be seen as one lip is thick and the other lip is flattened or even disappeared.
Diagnosis
According to medical history, clinical manifestations and gynecological examination, typical fibroids are easy to diagnose; however, it is more difficult to diagnose when the clinical symptoms are not typical and the fibroids are small, and some auxiliary examinations are needed.
1.Uterine cavity scraping Probe to explore the uterine cavity and feel the unevenness in the uterus when scraping, most of them have interstitial fibroids.
2.B-type ultrasound imaging can assist in the diagnosis.
3.Hysteroscopy.
Differential diagnosis
1.Pregnant uterus: history of menopause, early pregnancy reaction, positive blood and urine HCG, uniform enlargement of uterus in accordance with the month of menopause, soft texture, and a gestational sac in the uterine cavity as seen by ultrasound.
2.Uterine hypertrophy Uniform enlargement of uterus, no myoma nodules on ultrasound.
3, adenomyosis Secondary to history of dysmenorrhea, the uterus is enlarged during menstruation and shrinks after menstruation, ultrasound can assist in diagnosis.
4. Ovarian tumor Subplasmalemmal myoma with tissues should be differentiated from ovarian tumor, which is a solid or semi-solid mass with little relation to the uterus, and B ultrasound can assist in the differentiation.
5, pelvic inflammatory mass History of inflammatory infection, cystic mass, poor activity, positive tenderness, shrinking after anti-inflammatory treatment, can be diagnosed with the help of ultrasound.
6.Gravida Irregular vaginal bleeding often appears after menopause, rapid uterine enlargement, but positive urine HCG, B ultrasound can assist in the diagnosis.
【Treatment
There are non-surgical treatment and surgical treatment.
Surgical excision is not necessary for persistently asymptomatic fibroids, but is necessary if symptoms do progress with one or more of the following symptoms: pelvic mass, menstrual disorder, or infertility. At what age is it feasible to remove an asymptomatic fibroid? The classic answer is the size of 14 weeks of pregnancy or larger (15 cm in diameter). It is difficult to say why surgery is performed at this size, but experience suggests that fibroids will continue to grow, making late removal both necessary and difficult, and that enlarged fibroids make palpation of the uterine appendages difficult, potentially leading to missed ovarian tumors.
If the fibroids are treated because of their size, total hysterectomy is the most common measure. For a single large fibroid and the patient wishes to preserve the uterus, myomectomy is indicated. If the menstrual flow is excessive and the patient is anemic due to blood loss, total hysterectomy is the best option. It is not necessary to wait for the onset of anemia before considering total hysterectomy, because if the patient has a rich diet, even if she is in general discomfort or has excessive menstrual flow, it will not have a significant impact on the blood cell volume.
1.Non-surgical treatment
(1) Small fibroids and near menopausal fibroids without symptoms can be left untreated, but all of them should be followed up and observed, which can be done once in 3~6 months to find out the situation in time.
(2) Drug therapy: Although the fibroids are large but asymptomatic or near menopause, if the menstrual flow is excessive, androgens can be used, such as methyltestosterone 5mg sublingual or testosterone propionate 25mg intramuscular injection, the total amount of less than 250mg per month. recent studies have shown that progesterone plays an important role in the growth of uterine fibroids, and the progesterone antagonist mifepristone has the effect of shrinking fibroids. Mifepristone is taken orally 10~50mg daily, starting from the 1st~3rd day of menstruation for 3 months. It is suitable for the preoperative preparation of patients with large fibroids or severe anemia, and for the conservative treatment of patients with symptomatic fibroids in the perimenopausal period. During the treatment period patients experience amenorrhea, symptoms of dysmenorrhea and lower abdominal cramping and distension disappear, anemia symptoms are corrected, and fibroids shrink. Gonadotropin-releasing hormone agonist (GnRHa), a synthetic agent similar to endogenous gonadotropin-releasing hormone (GnRH), continues to bind to the GnRH receptor, inhibiting endogenous gonadotropin secretion and reducing estrogen and progesterone production to “depot” levels, thereby shrinking fibroids for therapeutic purposes. The indications for the treatment of fibroids are the same as those for mifepristone, but it is expensive. It can reduce the size of fibroids by 20% to 77% in 3-6 months, and it is recommended to reduce the size of fibroids by 35% to 65% in 3 months. Adverse effects mainly include hot flashes, bouts of sweating and other symptoms of low estrogen menopause, which usually appear 4-8 weeks after the application of GnRH and peak at 4 months; long-term application of GnRH can also cause abnormalities in bone metabolism. Other pharmacological treatments include Danazol, aromatase inhibitors, selective estrogen receptor (ER) modifiers and PR modifiers, which are not widely used and some are still in the experimental stage. In conclusion, the drugs for uterine fibroids have clear effects during medication, but the symptoms recur after stopping medication, so they are not long-term application drugs.
(3) Traditional Chinese medicine treatment: On the one hand, it is expected to shrink the fibroids, and on the other hand, it can reduce the symptoms.
(4) High intensity focused ultrasound: High intensity focused ultrasound (HIFU) treatment is to focus the acoustic energy from the ultrasound source on a point in the human tissue by means of focusing (transducer surface focusing, lens focusing or array focusing), forming a focused area with high acoustic intensity, and destroying the tissue cells in the focused area after a certain time of interaction between ultrasound and tissue cells. Tissue cells in the focus area are destroyed through the interaction between ultrasound and tissue cells for a certain period of time. It is very important to perform relevant examinations before treatment to exclude malignant tumors of the reproductive tract. In order to make the focusing area exactly in the predetermined target area, without off-target or mis-injury, ultrasound guidance technology and magnetic resonance imaging (MRI) guidance technology are currently used to achieve accurate display and localization of deep human lesions and monitoring of the whole treatment process.
Indications: Completed childbirth, unwilling to operate for some reasons and wishing to preserve the uterus, 10 cm tumor with pressure or uterus > 20 weeks of gestation. ④Severe vaginal bleeding. ⑤ The distance between the target area and the skin predetermined by ultrasound focusing.