gastric cancer refers to a malignant tumor that occurs in gastric epithelial tissue. More than 7% of the patients have no symptoms in the early clinical stage, and the corresponding symptoms caused by epigastric pain, gastrointestinal bleeding, perforation, pyloric obstruction, emaciation, fatigue, metabolic disorder and cancer spread and metastasis can occur at any age, especially at the age of 5-6, and the ratio of male to female incidence is 3.2-3.6: 1.
Gastric cancer has the characteristics of occult onset, missed diagnosis due to no obvious symptoms in the early stage, easy metastasis and recurrence, and poor prognosis.
The incidence of gastric cancer in China is high, and its mortality ranks first among all kinds of malignant tumors. Therefore, gastric cancer is a common disease that seriously harms the health of our people and should be paid attention to.
gastric cancer belongs to the categories of "fuliang", "accumulation", "epigastric pain", "choking" and "nausea" in traditional Chinese medicine.
etiology
there are two major risk factors for gastric cancer.
first, individual factors, that is, physical factors; For example: ① Among the blood group factors, the incidence of type A blood is high; ② Gastric cancer has family aggregation; ③ Mental factors; ④ Suffering from chronic atrophic gastritis, gastric ulcer, gastric polyp and other diseases.
second, environmental factors; Such as: ① lack or high content of trace elements in chemical factors, high content of SO4-2 and/or Se nitrate in water, etc. ② Microbial pollution factors, such as fungi and bacteria; ③ Dietary factors, such as regular consumption of fresh vegetables, fruits and protein foods, have protective effects, while eating more high starch, heavy salt, pickled, smoked and fried foods and bad eating behaviors.
Dissemination and metastasis
1. Direct spread: The tumor infiltrates around the stomach wall or deep, and can directly immerse into the abdominal wall and adjacent organs or tissues (liver, pancreas, omentum, transverse colon, etc.). Cancer cells can also spread along the submucosa, invade the lower esophagus upwards and invade the duodenum downwards.
2. Lymphatic metastasis: it is the most important mode of metastasis. The lymphatic metastasis rate of early gastric cancer can reach 1%, and the lymph node metastasis rate of advanced gastric cancer can reach about 7%. After cancer cells invade lymphatic vessels, they form emboli and transfer to lymph nodes all over the body.
3. Hematological metastasis: It mostly occurs in late stage, and cancer cells spread to liver, lung, bone, brain and other places through blood circulation. It can also be transferred to the skin around the umbilical vein.
4. Peritoneal implantation: After the tumor invades the gastric serosa, cancer cells fall off and are implanted in the abdominal cavity and pelvic cavity, causing extensive peritoneal and intestinal system membrane metastasis. Ascites can appear, and metastatic nodules can be touched at Douglas' fossa when anal digital examination is performed.
Clinical manifestations
(1) Symptoms
1. More than 7% of early gastric cancer has no obvious symptoms. With the development of the disease, nonspecific symptoms similar to gastritis or gastric ulcer may gradually appear, including fullness, discomfort or dull pain in the upper abdomen, pantothenic acid, belching, nausea, occasional vomiting, loss of appetite and melena.
2. The symptoms of advanced gastric cancer are pain in the stomach area, often biting, which has nothing to do with eating, but also similar to peptic ulcer pain, which can be relieved after eating. Abdominal fullness, heaviness, anorexia, abdominal pain, nausea, vomiting, diarrhea, emaciation, anemia, edema, fever, etc. < P > The main manifestations of cardiac cancer are subaxiphoid discomfort, pain or retrosternal pain, accompanied by eating obstruction or dysphagia. Cancers in the fundus of stomach and inferior cardia often have no obvious symptoms, and they do not attract attention until the tumor is huge and necrosis and ulceration cause upper gastrointestinal bleeding, or they do not pay attention until the tumor infiltrates to the cardia and causes dysphagia. Tumors in the body of stomach are more common in swelling type, and pain and discomfort appear later. Ulcerative cancer is the most common form of gastric antrum, so the symptoms of epigastric pain appear earlier. When the tumor extends to the secluded doorway, it can cause pyloric obstruction symptoms such as nausea and vomiting.
The spread and metastasis of cancer can cause ascites, hepatomegaly, jaundice and metastasis of lung, brain, heart, prostate, ovary, bone marrow and so on, resulting in corresponding symptoms.
(2) Signs
Most patients with gastric cancer have no obvious signs, and some patients have mild tenderness in the upper abdomen. The advanced gastric cancer located in pyloric sinus or stomach body can sometimes palpate a mass, which is often nodular and hard. When the tumor infiltrates into adjacent organs or tissues, the mass is often fixed and cannot be pushed. Female patients palpate a mass in the middle and lower abdomen, which often suggests that it is a krukenbe tumor. When gastric cancer has liver metastasis, nodular masses can be touched in the swollen liver. Obstructive jaundice can occur when abdominal metastatic masses compress the common bile duct. In patients with pyloric obstruction, the enlarged stomach type can be seen in the upper abdomen, and the sound of shock can be heard. The left supraclavicular lymph node can be enlarged when the cancer is transferred through the thoracic duct. When there is pelvic implantation in advanced gastric cancer, rectal digital examination can palpate nodules in the rectal fossa of bladder (uterus). Ascites can occur when there is peritoneal metastasis. Intestinal cavity constriction caused by small intestine or mesenteric metastasis can lead to partial or complete intestinal obstruction. Diffuse peritonitis caused by cancer perforation may cause supine board-like stiffness, abdominal tenderness and other symptoms of peritoneal irritation, and may also infiltrate the organs of adjacent cavities to form internal fistula.
(3) Common complications
1. When complicated with gastrointestinal bleeding, dizziness, palpitation, tarry stool and vomiting of brown matter may occur.
2. When the common bile duct is compressed by abdominal metastasis of gastric cancer, jaundice and clay color in stool may appear.
3. With pyloric obstruction, vomiting may occur, and distended stomach type, smell and shock sound may be seen in the upper abdomen.
4. Diffuse peritonitis caused by cancer perforation may cause supine board-like stiffness, abdominal tenderness and other peritoneal irritation.
5, gastrointestinal fistula is formed, and indigestible food is discharged.