Gastric cancer is a fatal disease of the stomach. Usually, its symptoms are not very prominent and often go undetected for a very long time. And this is one of the main reasons why gastric cancer or stomach cancer is a very serious ailment.
Gastric Cancer: An Introduction to Fatal Disease
Even with the advancement of medical science, gastric cancer continues to remain a big cause of cancer-related deaths in the world. Gastric cancer affects the lining of the stomach, which is located between the esophagus and the small intestine. Its purpose is to secrete enzymes and gastric acids that help in proper digestion of food. The stomach lining has epithelial cells and glands. The lining can get inflamed, which can lead to peptic ulcers and later, gastric cancer.
- Based on GLOBOCAN 2018 data, stomach cancer is the 5th most common neoplasm (abnormal growth) and 3rd most deadly cancers (malignant tumors).
- It is estimated to have been the cause of 783,000 deaths in 2018.
- About 1 in 12 oncological deaths are caused due to gastric cancer.
- Over one million cases of stomach cancer are diagnosed each year.
- Gastric cancer is more common in males. Also, the mortality from stomach cancer is higher among males.
- Its frequency is higher in developed countries.
Gastric cancers/gastric adenocarcinomas are divided into two categories (depending on anatomic site):
1. Cancers of gastric cardia: Such type of cancers occur in the upper region near to the esophagus. The pathogenesis of these cancers is not clear. However, they are known to have characteristics similar to Gastroesophageal Refluxes (GER) and esophageal adenocarcinoma.
2. Non-cardia gastric cancers: They occur in the mid and distal part of the stomach (all other parts of the stomach other than the top part that is connected with the esophagus). The non-cardia gastric cancers can be caused due to chronic gastritis, inflammation of mucous lining of the stomach and other environmental & behavioral reasons.
The occurrence of gastric cancer has been steadily declining in the world due to successful reduction of H. pylori infection. Approximately 90% of non-cardia gastric cancers can be attributed to the infection.
What are the Risk Factors associated with Gastric Cancer?
1. Genetics play a big role in increasing the risk of stomach cancer, for example: inherited mutations of GSTM1-null phenotype or CDH1 gene. Another example for increasing the risk of gastric cancer can be IL-17 and IL-10, polymorphisms of the interleukin genes.
2. Helicobacter Pylori is one of the main factors that can cause non-cardia gastric cancers.
3. Smoking or any other type of tobacco use can cause cardia gastric cancer. Even use of hookah and opium are possible risk factors for the disease.
4. Heavy usage of alcohol can cause gastritis by eroding the lining of the stomach. This will increase the risk of stomach cancer.
5. Occupational hazards such as chemical exposure to dust, high temperature particulates, metals such as chromium VI can increase the risk of stomach cancer. Common occupations associated with the following industries have higher risk:
a. Wood processing
b. Food machine operating
c. Rubber manufacturing
d. Coal mining
e. Metal mining, etc.
6. Even the presence of asbestos can moderately increase the risk of stomach cancer.
7. Diets with high amounts of salt, pickled foods and preserved meats can affect your chances of gastric cancer. Continuous consumption of red meat with high saturated fat content can cause inflammation of the stomach and may lead to gastric cancer.
8. Patients with pernicious anemia increase the risk of gastric cancer.
9. If you are exposed to radiation, it can become one of the risk factors for gastric cancer. A study on survivors of Hiroshima and Nagasaki established the relation between radiation exposure and incidences of gastric cancer. Childhood cancer survivors also have an increased risk of stomach cancer.
10. 5%-10% cases of gastric cancer are associated with Epstein-Barr Virus (EBV).
11. A lower socioeconomic status can prevent patients from getting access to medical treatment for an H. pylori infection. There is also the problem of lower access to fresh fruits and vegetables and all these factors can increase the risk of gastric cancer.
12. A large study reported that populations with blood group A positive were at a higher risk of stomach cancer.
13. The male population is more affected by gastric cancer. One reason can be the positive effects of estrogen on the female population.
14. Certain races and ethnicities are at a higher risk of the disease. For example: the incidences of gastric cancer have increased among indigenous population groups.
Remember that a majority of gastric cancers are influenced by your behavior and lifestyle, it means you can prevent the disease with adequate knowledge and care. Now, that you know all about the risk factors associated with stomach cancer, take measures to reduce the risk and lead a healthy, active life. The survival rates of gastric cancer are improving due to improvement in medical science and early detection. Do not ignore any symptoms that suggest unexplained weight loss, digestive distress, inflammation, etc.
In the next article, we will focus on symptoms of gastric cancer in detail. We will also discuss treatment modalities for stomach cancer.