An Introduction to Stomach Cancer
Stomach cancer is also called gastric cancer. Stomach cancer ranks amongst the five most common cancers in India. It is the second most common cause of cancer-related deaths among Indians within the age group of 15 and 44. Even though the incidence of stomach cancer is far less when compared to western countries, the increasing incidence of stomach cancer is a reason to worry. This article aims to explain stomach cancer briefly and how to recognize it.
Understanding the Stomach
To fully understand stomach cancer, it is imperative to know about the stomach, its layers, and parts.
The 5 Parts in a Human Stomach
- The part of the stomach where the esophagus (food pipe) is attached is called cardia.
- The upper part of the stomach where the curvature is high is called the fundus.
- The balloon-like part which is overwhelming in size is called the body or corpus.
- All these above 3 parts are termed as proximal stomach.
- The next 2 lowers parts are Antrum and Pylorus, which are together termed as distal stomach
- The 4th part, the Antrum is where the gastric juice and the food consumed mix well.
- The 5th or the final part, or the Pylorus acts like a valve. It helps in pushing the semi-digested food further into the duodenum part of the small intestine.
The Layers in a Human Stomach
- The innermost layer of the stomach is called the mucosa. This is the place where gastric juices are made and secreted.
- The next layer is called the submucosa
- The third layer is a very thick muscle layer called muscularis propria. This layer helps in moving and mixing the stomach content.
- The next layer is the subserosa
- The outermost layer is the serosa. The subserosa and serosa, together form the outer lining of the stomach.
Most cancers are formed in the cardia region of the stomach and most cancers develop in the innermost mucosa layer of the stomach.
Type of Stomach Cancer
- When the innermost lining of the stomach, the mucosa layer, develops cancer, it is termed Adenocarcinoma. This type is the predominant type among the various stomach cancer types. It is almost 90%-95%.
- Other types of stomach cancers are Lymphoma, Carcinoid tumor, etc. Lymphoma is cancer in the immune system tissues found in the stomach. Carcinoid tumor is cancer in the hormone-making cells of the stomach.
- There are lesser know other types of stomach cancer types like Gastrointestinal Stromal Tumor (GIST), squamous cell carcinoma, small cell carcinoma, and leiomyosarcoma, etc. Most of these types of stomach cancers are very rare.
How does Stomach Cancer Develop?
In the case of Adenocarcinoma, the most common type of Stomach cancer, cancer in the lining of the stomach’s mucosal layer develops rather slowly and it takes many years to develop as a matter of fact. The mucous lining of cancer undergoes pre-cancerous changes and they do not give any symptoms. For this reason, most stomach cancer cases go undetected for years. This is the sole reason why the mortality rate of people with stomach cancer is higher among the various cancer types.
Few Facts about Stomach Cancer
- Stomach cancer is more common in men than in women. Men are affected almost twice as women and the ratio is almost 2:1.
- Older men are more affected
- Certain bacteria like H. pylori and certain virus-like Epstein-Barr virus are linked to stomach cancer.
- Consuming more deep-fried oily items made of repeatedly used oil is one of the common causes of stomach cancer.
- Frequent tobacco use is also linked to an increased incidence of stomach cancer.
- Alcohol abuse is one of the causes.
- Obesity is also linked to stomach cancer.
- Some blood groups like A and AB are more prone to stomach cancer than O type.