Pancreatic true cyst
Introduction
Introduction to pancreatic true cyst The pancreatic true cyst (truepancreatiticcyst) is rare, the cyst occurs in the pancreas, and the inner wall of the capsule is composed of a duct or glandular epithelium. Patients with small pancreatic cysts have no obvious symptoms, but are found during physical examination, abdominal surgery or autopsy. Due to the wide application of CT, especially B-mode ultrasound, the incidence rate has increased significantly in recent years, and occasionally huge cysts can cause compression symptoms. The treatment of this disease is mainly cystectomy. However, the presence or absence of a tumor should be first investigated before removal. basic knowledge The proportion of illness: 0.001% Susceptible people: no special people Mode of infection: non-infectious Complications: acute peritonitis jaundice pleural effusion ascites gastrointestinal bleeding
Cause
The cause of pancreatic true cyst
Congenital factors (15%):
More common in children, is a pancreatic duct, caused by abnormal development of acinar, including simple single or multiple small cysts in the pancreas, dermoid cysts, congenital polycystic diseases involving pancreas and other organs, and hereditary systemic mucus Cystic fibroproliferative disease with abnormal glandular secretion.
Abnormal cell proliferation (20%):
Caused by abnormal proliferation of pancreatic epithelial cells or acinar cells, pancreatic cystadenoma, cystadenocarcinoma, cystic teratoma, etc. are common.
Hemorrhagic or necrotic lesions (18%):
Caused by intra-pancreatic hemorrhage or necrotic lesions.
Parasitic infections (20%):
Often caused by Echinococcus or porcine cysticercosis.
Other factors (20%):
It is a clinically common type of true cyst, which is caused by poor drainage of pancreatic duct due to various reasons, and pancreatic juice retention. Common causes are pancreatic duct stones, scar contraction around tumor or pancreas, and tumor compression. The pancreatic duct is narrow or obstructed.
Pathogenesis
In animal experiments, it was found that if the pancreas was completely ligated, the distal end did not form a retention cyst, and pancreatic atrophy was produced. It is estimated that the cyst is due to obstruction or incomplete obstruction of the pancreatic duct, and the discharge of the secretion is blocked. The single or multiple cysts formed are generally small in size, and the cysts are characterized by large and small time. When the secretion is partially discharged, the cysts become smaller, and the cyst wall is covered by a single layer of cubic or flat epithelium. Larger cysts, the epithelial cells in the inner layer of the wall can be completely degraded by the internal pressure of the cyst, inflammation and enzyme digestion, completely losing the structure of the epithelial cells. At this time, similar to the pseudocyst, but in the vicinity of the retention cyst or other areas, it can be seen Some acinar and catheter have different degrees of cystic dilatation, this feature can be distinguished from pseudocysts, and there are few inflammatory exudative components of sputum, and various pancreatic enzymes are high, clinically mostly chronic pancreas Symptoms of inflammation, manifested by repeated episodes of abdominal pain, and radiation to the back, occasionally larger cysts can cause compression symptoms, ultrasound or CT examination, can show that the site of the mass has a clear boundary In the density zone, pancreatic duct angiography can show cysts and their location, blood and urine amylase are mostly in the normal range. In the treatment, for larger cysts that cause clinical symptoms, the cysts can be removed or removed together with the surrounding pancreatic tissue. There are not many adhesions around this type of cyst. It is easier to separate during surgery. When the cyst of the pancreas is small with duodenal papillitis and stenosis, sphincter formation at the opening of the pancreatic duct can relieve the symptoms. In the exploration, attention should be paid to the presence or absence of a tumor, and whether the cyst is caused by tumor compression.
Prevention
Pancreatic true cyst prevention
There is no effective preventive measure for this disease. Early detection and early diagnosis are the key to the prevention and treatment of this disease. Pay attention to personal hygiene in life, avoid eating cold and spicy food.
Complication
Pancreatic true cyst complications Complications Acute peritonitis jaundice pleural effusion ascites gastrointestinal bleeding
1. Secondary infection: The patient may have toxic symptoms such as chills and fever, white blood cells, etc. The upper abdominal mass may have obvious tenderness. The increase of intracapsular pressure may cause rupture and hemorrhage of the cyst, which must be highly valued. In addition to the application of antibiotics, active surgery, external drainage should be performed. In recent years, with the development of radiological interventional techniques, percutaneous cyst drainage can be performed under the guidance of B-ultrasound or CT, which can drain the pus in the cyst. The capsule can be rinsed with an antibacterial drug through a drainage tube, and the effect is good.
2. Cyst rupture: The cyst may be ruptured due to changes in intracapsular pressure or external force. It is characterized by sudden upper abdominal pain and cyst shrinkage or disappearance. Acute peritonitis signs appear. Abdominal puncture can extract amylase-rich Liquid, due to the corrosion and infection of the cyst fluid, the cyst can spontaneously penetrate into the digestive tract, forming internal hemorrhoids, such as cysts - colon fistula, etc., and some may cause gastrointestinal bleeding, cyst rupture is a serious concurrency Symptoms, once present, should be surgically drained as soon as possible.
3. Bleeding: Cysts followed by blood is a serious complication that directly threatens the patient's life. There are many large arterial vessels around the upper abdomen and pancreas, such as the left gastric artery, right gastric artery, splenic artery, splenic vein, etc. due to cysts. Infection, compression and pancreatic enzyme erosion can cause rupture and bleeding of these large blood vessels. At this time, the patient can have sudden abdominal pain, pale complexion, rapid heart rate, blood pressure drop and other shock symptoms, and the abdominal mass can be significantly increased, such as patients. Extracapsular drainage has been performed, and there is a large amount of blood in the drainage tube. This complication is extremely fast, and should be urgently explored to stop bleeding or remove the affected organ according to the bleeding condition.
4. Other complications: If the cyst has a small rupture, it can form pancreatic ascites, and some patients may have pancreatic pleural effusion; the pancreatic head cyst compresses the lower end of the common bile duct to cause obstructive jaundice; the cyst compresses the portal system. It can form pancreatic portal hypertension; when the islet function declines, hyperglycemia can occur.
Symptom
Symptoms of pancreatic true cysts Common symptoms Intestinal dysfunction constipation painful abdominal discomfort nausea blunt pain septic shock
The clinical symptoms of pancreatic cysts are related to the type, size, location of the cyst and the stage of the primary disease. Some cysts are small in size and can be free of any symptoms, while larger cysts can produce more obvious symptoms.
1. Symptoms caused by cyst itself: Fullness and discomfort in the upper abdomen, pain is one of the important symptoms of pancreatic cysts, accounting for 80% to 90%. Pain is related to the growth of cysts, often radiating to the left shoulder and lower back. The nature of pain is mostly persistent dull pain, pain, paroxysmal colic, and the cause of pain. It is generally thought to be caused by cyst compression of the gastrointestinal tract, retroperitoneal and celiac plexus, if cyst Intracapsular hemorrhage or infection can also cause pain, and paroxysmal pain can occur when cholelithiasis is combined.
2. Symptoms caused by compression of surrounding organs: Direct compression and transition of the cyst to the gastrointestinal tract or through nerve reflex, as well as insufficient exocrine function of the pancreas, can cause disorders of the gastrointestinal function, often manifested as upper abdominal discomfort, fullness Increased after meals, nausea and vomiting, loss of appetite, and diarrhea or constipation, such as cysts located in the head of the pancreas, can compress the lower end of the common bile duct to cause obstructive jaundice; compression of the duodenum or antrum can cause completeness or Incomplete pyloric obstruction; compression of the inferior vena cava can cause lower extremity edema or superficial varicose veins; compression of the kidney or ureter can cause urinary tract obstruction and hydronephrosis; compression of the portal system can cause ascites or portal hypertension.
3. Consumptive symptoms: Consumption caused by acute and chronic pancreatitis, gastrointestinal dysfunction caused by cysts, and fearing psychosis caused by increased pain after eating, can cause significant weight loss and weight loss. Insufficient exocrine function of the pancreas can cause fat digestive dysfunction and steatorrhea.
4. Symptoms caused by complications of cysts: Cysts may have chills and fever, heart rate and even sepsis when secondary infections occur; such as acute hemorrhage in the capsule, which may manifest as a rapid increase in cysts and shock symptoms; Symptoms of peritoneal inflammation.
Examine
Examination of pancreatic true cysts
Blood routine can be manifested as increased white blood cells, especially in secondary infections, sometimes elevated blood sugar, positive urine sugar, is a manifestation of islet function, oil droplets appear in the stool, indicating insufficient pancreatic exocrine function, in cyst cases Serum trypsin and plasma antithrombin are also often elevated, contributing to the early diagnosis of pancreatic cysts.
X-ray inspection
(1) Abdominal plain film: For large cysts, abdominal plain film can show soft tissue block shadow, a small number of patients can show calcification of pancreas or cyst, which is patchy, which is caused by pancreatitis complicated by pancreatic stones or calcification. The calcification of the wall is a curved dense linear shadow, which can be used to show the location, size and shape of the cyst. In a few cases, the left diaphragmatic elevation can occur. In patients with pleural effusion, the rib angle can be blurred, and the cyst is secondary to infection. Abscess, can appear soapy gas shadow.
(2) Gastrointestinal barium angiography: including upper gastrointestinal barium meal and barium enema angiography, about 80% of cases are positive, mainly for the compression and displacement of the cyst to the stomach, followed by The duodenum, duodenal jejunum, transverse colon, colonic spleen and descending colon, etc., can be used to indirectly determine the location, size, shape and relationship of the cyst to the pancreas, except for small or small cysts. The pancreas is far away and can usually be diagnosed correctly.
(3) pancreatic duct angiography: pancreatic ductography has many methods, currently used endoscopic retrograde cholangiopancreatography (ERCP), intraoperative pancreatic ductography (OPT), drainage tube pancreatic ductography, and percutaneous transhepatic Puncture cholangiography (PFC), etc., ERCP can only show pancreatic duct compression, displacement and stenosis, and whether the cyst is connected with the pancreatic duct. It can not provide more signs for the diagnosis of cysts. OPT has been used more and more in recent years. Diagnosis of smaller cysts in the pancreas.
(4) Angiography: Selective celiac artery and superior mesenteric artery angiography can show that the artery and its branches are compressed and displaced, and there is a sign of a "ball" around the cyst. The blood vessels are sparse and straight, and there is no blood vessel distribution in the capsule. It is its characteristics.
2. Ultrasound examination
B-ultrasound is the preferred method of examination in clinical practice. The correct rate of diagnosis of pancreatic cysts is as high as 90%. B-ultrasound can detect the location, size, thickness of cyst wall and the number of cysts in pancreatic cysts. Large cysts often squeeze surrounding tissues. , so that it is pressed and displaced.
3. CT examination
CT can accurately display the location and size of the pancreatic cyst, determine the thickness of the cyst wall, the density of the capsule contents, detect the presence or absence of intracapsular septum or new intracranial organisms, and understand the relationship between cysts and surrounding organs and important blood vessels. To provide adequate reference for diagnosis and treatment, especially for obesity or gastrointestinal flatulence, patients with B-ultrasound can not correctly diagnose, CT shows its superiority.
4. B-ultrasound or CT-guided needle biopsy
After the diagnosis of pancreatic cysts is basically clear, the nature of the cysts must be identified. It is often difficult to identify by relying solely on imaging techniques, and the biopsy of pancreatic cysts can provide a powerful help for differential diagnosis. Under B-mode or CT positioning. Select the puncture point, determine the direction of the needle and the depth of the needle, and minimize the damage of the surrounding organs and large blood vessels. Generally, serious complications will not occur. Through the needle biopsy, the wall tissue and the cyst fluid can be obtained for tissue. Pathology, amylase in cyst fluid, tumor markers, cystic fluid cytology, cystic fluid viscosity, etc., help to identify the nature of pancreatic cysts.
Diagnosis
Diagnosis and differentiation of pancreatic true cyst
diagnosis
Physical examination: The upper abdominal mass is the most important positive sign of pancreatic cysts. About 90% of the patients can reach the mass in the abdomen. The mass is usually located in the midline of the upper abdomen or slightly to the left. The size is different, round or oval, and the surface is smooth. It is sexy, has tension, some borders are clear, there are different degrees of tenderness, and it does not move with breathing.
In addition, patients with chronic cysts tend to be thinner, such as cysts compressing the lower end of the common bile duct, which can be found to have varying degrees of jaundice.
1. Clinical manifestations.
2. Physical examination.
3. Laboratory tests and other auxiliary inspections.
Differential diagnosis
1. Common bile duct cyst: for congenital choledochal dysplasia, clinically characterized by intermittent abdominal pain, jaundice and abdominal cysts, large cysts are not easily differentiated from pancreatic cysts, ERCP, CT (including conventional CT or PTC spiral CT) Biliary tract imaging (SCTC), MRI and magnetic resonance cholangiography (MRC) can show cystic dilatation of the common bile duct, which is helpful for identification.
2. Mesenteric cysts: mostly occur in the small mesentery, the location is mostly near the umbilicus, the left and right range of motion is large, X-ray examination shows that the cyst is adjacent to the intestine and the lumen is narrowed or elongated, the stomach and duodenum Generally, no displacement occurs, and duodenal fistula does not enlarge.
3. Omental cyst: The cyst has a large degree of activity, but it is not easy to distinguish from pancreatic cyst when it is stuck or close to the large curved side of the stomach. The upper digestive tract barium examination or CT can show that the cyst is located in front of the small intestine, and the transverse colon is often due to cyst. Pushing and moving closer to the ascending colon, resulting in deformation of the colonic liver, the stomach can be pushed to shift or deform, but the duodenum is unchanged.
4. Pancreatic abscess: can be expressed as chills, fever, white blood cells and other acute infection symptoms, the patient complained of abdominal pain, the upper abdomen may have obvious tenderness, B-ultrasound is very similar to pancreatic cyst, but the abdominal plain film or CT examination found cyst When there is a bubble, the diagnosis can be made clear. If necessary, fine needle aspiration under B-ultrasound or CT positioning can be performed, and the cyst fluid can be extracted for analysis.
5. Other cysts or tumors: Pancreatic cysts must also be associated with hepatic cysts, hepatic hydatidosis (hydatidosis), retroperitoneal cysts, renal cysts, hydronephrosis, gastric or duodenal leiomyosarcoma necrosis and other cystic lesions And gastric cancer, spleen tumor, adrenal tumor and other phase identification.
