Stomach cancer, also called gastric cancer, develops due to abnormal growth and multiplication of the cells lining the inner layer of the stomach. Cancer is the uncontrolled growth of abnormal cells. The accumulation of these extra cells forms a mass of tissue called tumour.
According to the type of tissue in which the cancer originates stomach cancers are classified as:
- Adenocarcinoma: It is the most common type of stomach cancer and develops from the cells in the mucosa, the innermost lining of the stomach.
- Gastrointestinal stromal tumours: These tumours arise from the muscle layers of the stomach. They can range from being benign to malignant, when they are called sarcomas.
- Carcinoid cancers: These are rare cancers start in neuroendocrine cells in the gastrointestinal tract.
- Lymphomas:These rare cancers develop in the lymphatic tissue, and are usually treated by chemotherapy.
The exact cause of stomach cancer is not known, however certain factors such as advancing age, gender, family history, H. pylori infection, diet, smoking, and certain medical conditions may increase your risk of developing stomach cancer.
In the early stages of stomach cancer, a patient may feel indigestion and stomach discomfort, a bloated feeling after eating, mild nausea, loss of appetite, and heartburn. As the cancer grows you may have weight loss, vomiting blood, blood in the stool, lumpiness in the stomach, tiredness and anaemia.
The diagnosis of stomach cancer is made by endoscopy and biopsy.
The staging of the stomach cancer is done to determine whether the cancer is confined to the stomach or whether it has spread to local lymph nodes, surrounding tissue and to distant organs such as the liver and lung. A CT scan of the chest and abdomen will be done and sometime staging laparoscopy will be done before committing to an operation to remove some or all of the stomach with surrounding fat and lymph nodes (partial or total gastrectomy).
Patients suitable for surgery will usually be offered chemotherapy both before and after the operation.