Gastric cancer
Gastric or stomach cancer represents the second leading cause of cancer-related death in the world.
Its incidence varies in different countries; the highest rates have been reported in Japan, China, South America, and Eastern Europe.
The number of cases increases significantly after the age of 50.
Causes by which a person can develop Gastric Cancer
The cause of gastric cancer appears to be multifactorial and the causative factors vary in different parts of the world.
They can act individually or combine in different ways to cause someone to develop gastric cancer:
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Environmental factors.
Consumption of diets high in carbohydrates and salt, as well as nitrates and nitrites commonly found in vegetables and cured meat, have been associated with an elevated risk of gastric cancer. -
Genetic factors.
The presence of families with several members with gastric cancer as well as the description of familial cancer syndromes (Lynch syndrome) in addition to the fact that it has been observed that first degree relatives of subjects with gastric cancer have a 2 to 3 times higher incidence of malignancy than suggest the possibility that still unknown genes are involved in the development of gastric cancer. Until now, there is no genetic test that can predict whether or not an individual will develop gastric cancer. -
Helicobater pylori (Hp) infection.
Hp is a bacterium that infects the stomach. This infection is the most common cause of chronic gastritis. Some studies suggest that people infected with Hp have a 3 to 6 higher frequency of gastric cancer.
Although the exact relationship between Hp acquisition and cancer development is not well established, it is now accepted that Hp causes chronic gastritis. This chronic inflammation reduces the mucus layer, exposing the cells of the gastric mucosa to a greater number of toxic substances.
Chronic Hp infection can eventually cause destruction of the gastric mucosa, causing arophic gastritis, which is a premalignant condition. Not all people with gastritis are infected by Hp, and it is important to highlight that not all Hp-infected subjects require eradication treatment and it is a low percentage that develops premalignant lesions.
The latter can be identified by endoscopy of the stomach, which is recommended in those cases in which their symptoms do not respond to medical treatment, have presented bleeding or weight loss.
How does it manifest?
Symptoms depend on the location and size of the tumor.
Patients may complain of abdominal pain, early satiety, bloating.
Occasionally weight loss, nausea, anorexia, vomiting, or anemia due to occult bleeding.
Diagnosis
Endoscopy with biopsies is the best diagnostic method and should be performed whenever a gastric neoplasia is suspected.
Treatment
The only curative procedure is surgical removal of the tumor along with all the adjacent lymph nodes.
Gastric cancer is radio resistant and generally chemotherapy and radiotherapy are applied to alleviate the symptoms since they do not improve survival.
In special cases in which the cancer is diagnosed in early stages or endoscopy shows a premalignant lesion, endoscopic resection can be attempted and major surgery avoided.
This procedure is called endoscopic mucosal resection and is used in lesions that affect the most superficial layer of the gastric lining, or mucosal layer if the tumor extends to deeper layers.
Before carrying out this procedure, it is necessary to have biospies that confirm the diagnosis, as well as endoscopic ultrasound, which is a method by which the gastric layer or layers that the tumor invades can be determined.