Small intestinal leiomyosarcoma

Brief introduction of small intestinal leiomyosarcoma Small intestinal leiomyosarcoma is a malignant tumor originating from the muscular layer of the small intestine, the submucosal muscle layer and the vascular smooth muscle of the intestinal wall, and is the most common type of small intestinal connective tissue malignant tumor. In the small intestine non-slipoma, the ratio of leiomyosarcoma to leiomyomas is 2 to 4:1 in the jejunum, followed by the ileum and duodenum. basic knowledge The proportion of the disease: the incidence of this disease in the middle-aged and elderly people over 50 years old is about 0.005%-0.007% Susceptible people: no specific population Mode of infection: non-infectious Complications: intussusception, intestinal obstruction, gastrointestinal bleeding, anemia

Causes of small bowel leiomyosarcoma

(1) Causes of the disease

Small intestinal leiomyosarcoma originates from the smooth muscle tissue of the small intestine wall, mostly round or lobulated, with clear boundaries, expansive growth, and low infiltration rate to surrounding tissues.

(two) pathogenesis

During the growth process, leiomyosarcoma can partially protrude into the intestinal lumen, but most tumors form a large mass outside the intestinal lumen, or a dumbbell type protruding to the inside and outside of the intestinal wall.

1. Good hair

The leiomyosarcoma can be distributed throughout the small intestine. The distribution of each segment is different, but most people think that it is more common in the jejunum than in the ileum and duodenum. Domestic data report 1033 cases of small intestinal leiomyosarcoma, which occurs in the jejunum 422 For example, 40.8%, 298 cases of ileum, accounting for 28.8%, 207 cases of duodenum, accounting for 20%, 83 cases of jejunum junction, accounting for 8%, 23 cases were not located, accounting for 2%.

2. Pathological morphology

Small intestinal leiomyosarcoma is nodular growth, with a clear perimeter, most of which have a complete envelope, showing eccentric growth; the cut surface is grayish or grayish red, and weaving fiber bundles are also visible; soft, brittle, individual pedicle, Often single-shot, multi-stolen only accounted for 1 to 3%.

According to the growth mode of leiomyosarcoma, the clinical classification is divided into four types:

(1) intraluminal type: about 65%, the mass protrudes into the intestinal lumen, hemisphere or globular, the surface mucosa often has ulcer formation, and a few can be pedicled with lumps.

(2) intra-wall type: about 15%, tumor ring infiltration of the intestine, late stage of intestinal stenosis and obstruction symptoms, intraluminal tumor volume is generally small, and the symptoms appear earlier, mainly intussusception, Intestinal obstruction and bleeding.

(3) extraluminal type: about 8%, early can be asymptomatic, often grows to a considerable time before symptoms appear. This type of abdominal mass is more common, when the tumor grows to a certain extent, the center can be bleeding And necrosis, the tumor part is cystic, the incidence of surface mucosal ulcer is high, the tumor can be broken and communicate with the intestinal lumen, forming a tunnel-like fistula, causing bleeding, manifested as black stool, tar-like stool, occasionally tumor infiltrating the intestinal wall, Causes ischemia, necrosis and perforation.

(4) Internal and external cavity type: about 10%, the tumor protrudes into the cavity and outside, forming a dumbbell shape.

3. Pathological diagnosis

Tumors derived from smooth muscles are pathologically judged to be benign or malignant, sometimes difficult. The identification is mainly based on paraffin sections. Different opinions differ on the diagnostic criteria. Some people think that there are 5 mitotic figures in every 20 high power fields. For malignant criteria, more than 5 mitotic figures should be diagnosed as leiomyosarcoma; Ranchod believes that more than 3 mitotic figures per 10 high-power fields are leiomyosarcoma; Akwsri believes that 1/10HPF can be classified as malignant; Berg considers atypical mitotic figures, The pleomorphism and deep staining of the nucleus are the basic characteristics of sarcoma; Huang Zonghai et al. determine the good and malignant according to the size of the tumor, the degree of cell richness, the heteromorphism of the nucleus and the number of mitotic figures. Generally, the mitotic image is seen every 25 high-power fields. ~5 are low-grade malignant leiomyosarcomas, and more than 5 mitotic figures are leiomyosarcoma.

4. Pathological grading

According to the density of tumor cells, cell and nucleus heteromorphism, the number of nuclear fission of 25 high power field (HPF) was continuously calculated in the active area of tumor cell growth. The edge of the tumor invaded the mucosa and vasculature of the mucosa, and the tumor tissue showed no degeneration and necrosis. Cystic changes, combined with tumor recurrence and metastasis, can be classified into three levels: leiomyosarcoma:

Grade I: medium cell density, spindle-shaped cells, partial cell obesity, mild heteromorphism, nucleosis number is 2-8/25HPF, with an average of 5, half of the peritumoral tissue invasion, 1/3 Tumor necrosis;

Grade II: The tumor cells are mostly high-density, the cell morphology is irregular and the obese spindle cells are dominant, the nuclear chromatin is rough, the cytoplasm is less, and there is moderate heteromorphism. The number of nuclear fission is more than 10-20/25HPF, the average For 12, 2/3 see peritumoral invasion, half of them have tumor necrosis or cystic changes;

Grade III: high density of tumor cells, increased rod-shaped cells and irregular cells of obesity, megakaryocytes and multinuclear tumor cells, severe heteromorphism, and the number of nuclear divisions is 30-60/25HPF, with an average of 45, 2/3 See the peritumoral invasion, half of the necrosis and cystic changes.

Grade I has a better prognosis and grade III is the worst.

5. Transfer route

There is very little lymph node metastasis, prone to hematogenous metastasis to the liver, peritoneal and tumor bed implantation, peritoneal implantation rate of 10 to 15%, liver metastasis rate of 7%, and extra-abdominal distant parts are less common.

Small intestinal leiomyosarcoma prevention

1. Smoking banned alcohol: It is the primary measure to prevent throat cancer. The smoke is the hottest leader. The wine is the hottest and hottest. Smoking and drinking are extremely harmful to the pharynx.

Second, light diet: Where the ginger pepper mustard and all the spicy hot things will hurt the mucous membrane of the throat, should avoid eating these spicy and fried foods, eat more fruits and vegetables containing vitamin C.

Third, pay attention to oral hygiene: pay attention to personal hygiene, wash hands frequently. In the morning and evening, you can use a light salt water to rinse your mouth. After you rinse your mouth, you can drink a cup of light salt water to clean and moisten the throat, improve the throat environment and prevent bacterial infection.

Fourth, strengthen exercise: usually participate in physical exercise is also one of the measures to prevent throat cancer, enhance the body's defense capabilities, because the body's immunity and throat resistance is the most likely to cause repeated attacks of throat disease.

Small bowel leiomyosarcoma complications Complications, intussusception, intestinal obstruction, gastrointestinal bleeding, anemia

Intussusception, intestinal necrosis and anemia are common complications of this disease.

Intestinal obstruction

Tumor growth to a certain extent can make the intestinal lumen smaller, causing incomplete or complete intestinal obstruction.

2. Gastrointestinal bleeding

More common, long-term chronic blood loss can cause anemia.

Symptoms of small intestine leiomyosarcoma Common symptoms Abdominal pain, bloating, diarrhea, abdominal mass, lack of appetite, anemia, peritoneal irritation, weight loss, cachexia

The course of leiomyosarcoma is usually about one year. Early tumors are small and without ulcers. They are often asymptomatic. The tumor grows to a certain volume or has symptoms when bleeding.

The main clinical symptoms are abdominal pain, abdominal distension, abdominal mass and gastrointestinal bleeding. There may be anemia, weight loss, fatigue, loss of appetite, fever, etc. Some patients have diarrhea, fever or cachexia due to tumor stimulation of small intestinal secretion, and some tumors. It is ruptured and has a peritoneal irritation.

Abdominal pain

About half of the patients complained of abdominal pain, but the site and nature were non-specific, mostly manifested as dull or dull pain, and there was no obvious regularity in abdominal pain.

2. Intestinal obstruction

Tumor growth to a certain extent can make the intestinal lumen smaller, causing incomplete or complete intestinal obstruction, endoluminal sarcoma with the peristalsis and intestinal contents to the distal side, forming intussusception, the symptoms of incomplete intestinal obstruction, can be Self-relieving, and repeated episodes are intermittent, leiomyosarcoma is more common in extraluminal type, and larger in volume, easy to cause intestinal torsion, causing strangulated intestinal obstruction, persistent abdominal pain, paroxysmal aggravation, obvious abdominal distension, Frequent vomiting, no anal exhaust and defecation.

3. Gastrointestinal bleeding

More common, most of the fecal occult blood positive or intermittent melena, duodenal and proximal jejunal leiomyosarcoma can appear hematemesis, long-term chronic blood loss can cause anemia.

4. Abdominal mass

Half of the patients have a mass in the abdomen as the first symptom. The extraluminal type is more common. At the beginning, due to the small activity of the small intestine, the mesangial is free, the tumor position is not fixed, and it can be pushed. The tumor can be accompanied by intussusception. Hidden time, as the tumor grows, the activity is getting smaller and smaller, or even completely fixed. The mass consists of an enlarged tumor, a large omentum that accumulates and agglomerated lymph nodes.

5. Signs

Anemia can be found in the examination, the abdomen can touch the mass, its size can be promoted, accompanied by mild tenderness, duodenal leiomyosarcoma often touches the tumor located in the right upper abdomen, the tumor at the beginning of the jejunum In the left upper abdomen, a bump with an unclear boundary is sometimes touched, and in the rest of the jejunum and ileum, the mass is indefinite due to its large degree of activity.

Examination of small intestinal leiomyosarcoma

1. Histopathology: Microscopically, tumor cells like smooth muscle cells are arranged in a braided shape, and cytoplasm rich red staining may have calcification, mucus degeneration or glassy changes.

2. Blood test: There may be a decrease in hemoglobin and an increase in erythrocyte sedimentation rate.

3. Fecal occult blood test: fecal occult blood can be positive when the tumor surface ulcers.

Film degree exam

X-ray barium angiography

In particular, double-intensity examination of small intestine intubation is helpful for diagnosis. It is easier to find in endoscopic tumor examination. Contrast imaging is helpful for the diagnosis of duodenal tumor, but for ileal mass, due to intestinal fistula The images overlap, and the general examination method is not easy to find the lesion. The X-ray manifestations of the disease can be divided into direct signs and indirect signs:

(1) Direct X-ray signs: 1 The tumor boundary is clear, the angle between the two ends and the normal intestinal wall is acute, round or elliptical or nodular; 2 positive "3" or anti-"3" sign; 3 umbilical Sample or bovine eye-like shadow; 4 irregular tunnel-like fistula leading to the tumor cavity outside the intestinal lumen; 5 irregular tumor cystic sac and/or air shadow, standing position gas, liquid level or Gas, liquid, sputum three layers of shadow; 6 mucosal part disappeared, part of the arc or transverse shape; 7 tumor soft tissue shadow.

(2) Indirect signs: 1 local barium is blocked by fast or different degrees; 2 local intestinal lumen is narrowed; 3 local intestinal fistula and/or peripheral intestinal fistula or organ are under pressure; 4 proximal intestinal lumen is different Expansion; 5 occasional tumor calcification.

2. CT scan

Abdominal CT examination is of great significance for the diagnosis of leiomyosarcoma at the beginning of the duodenum and jejunum. CT is an eccentric irregular soft tissue mass connected to the intestine, usually 5cm in diameter, with the transition of the surrounding bowel, the mass The low-density area caused by necrosis and the formation of ulcers and fistulas can also be seen. Because the tumor is rich in blood vessels, it is obviously unevenly enhanced after enhancement. When a large ulcer is formed and communicates with the intestinal lumen, the contrast agent is filled or gas-liquid is formed. In the plane, there are very few calcifications in the tumor, and the tumor can directly invade the surrounding structure.

3. Colonoscopy

Patients with suspected proximal jejunum or distal ileal lesions may be treated with enteroscopy or colonoscopy, and may be easily diagnosed by biopsy, but only for observation of part of the small intestine.

4. Selective mesenteric angiography

Can show tumor angiography, the boundary is more clear, the amount of bleeding 0.5ml / min mesenteric angiography can show that the contrast agent escapes the blood vessels; bleeding stops or the amount of bleeding <0.5ml / min can not show contrast agent spill, but there are A blood vessel-rich tumor may be found.

5.99mTc imaging

When the bleeding rate is only 0.05~0.1ml/min, the technique can detect that the radionuclide escapes from the blood vessel into the intestinal lumen, and the detection rate of small intestinal tumor hemorrhage is high, but the localization rate is low.

6. Exploratory laparotomy

The diagnosis of small intestinal leiomyosarcoma is difficult. It is often misdiagnosed as other diseases in clinical practice. There are unexplained abdominal pain, history of weight loss and melena, and there is an active mass in the abdomen. When the fecal occult blood is positive, even if no abnormality is found on the X-ray examination, it should be Considering the possibility of small intestinal malignant tumors, especially leiomyosarcoma, laparotomy should be performed as soon as possible. Clinical data show that about one-third of patients need surgical exploration to confirm the diagnosis.

Diagnosis and differential diagnosis of small intestinal leiomyosarcoma

diagnosis

The diagnosis of small intestinal leiomyosarcoma is difficult. It is often misdiagnosed as other diseases in clinical practice. It is more than 40 years old, with clinically unexplained abdominal pain, abdominal distension, abdominal mass and/or gastrointestinal bleeding, or anemia, weight loss, fatigue, loss of appetite. Diarrhea, fever or cachexia, etc., should be thought of the possibility of this disease, physical examination of the upper right or left upper abdomen has a border with unclear mass, activity is greater and the site is uncertain, fecal occult blood test is positive, and X-ray no abnormalities should be highly suspected small Leiomyosarcoma, clinical diagnosis is mainly based on histopathological diagnosis, laparotomy should be performed early, clinical data show that about one-third of patients need surgical exploration to confirm the diagnosis.

Differential diagnosis

1. Duodenal leiomyosarcoma should be differentiated from gallbladder disease: ileal leiomyosarcoma should be differentiated from ovarian tumors in women; some cystic leiomyosarcoma is easily misdiagnosed as mesenteric or omental cyst.

2. Identification of benign and malignant small intestinal smooth muscle tumors: The prognosis of leiomyomas and leiomyosarcoma is quite different, but the identification of the two is sometimes quite difficult. Huang Zonghai et al suggest that the malignant criteria of small intestinal smooth muscle tumors are: 1 the number of mitotic divisions of tumor cells is 2/25 HPF, More than 5 can be diagnosed as leiomyosarcoma; 2 tumor cells are mildly above the shape; 3 cell density is above moderate; 4 tumor cells infiltrate surrounding tissues; 5 tumor diameter 6cm; 6 tumor with necrosis and cystic Change, there is 1 plus any of the following, or no 1 and the last three have to consider the possibility of viciousness.

The material in this site is intended to be of general informational use and is not intended to constitute medical advice, probable diagnosis, or recommended treatments.