Stomach is a hollow muscular sac like organ that plays a major role in the digestion of food. It is located in the left upper part of the abdomen just below the ribs. Stomach receives and holds the food and starts to digest it by secreting gastric juice. The food and gastric juice are mixed and then emptied into the first part of the small intestine called the duodenum.
Stomach cancer, also called gastric cancer, is a disease in which malignant cells form in the lining of the stomach. Stomach cancer generally develops slowly and do not show any prominent sign or symptom.
Types of Stomach Cancer
- Adenocarcinomas: These Cancers develop from the cells that form the innermost lining of the stomach (known as the mucosa). They account for 90 – 95 % of Stomach Cancers.
- Lymphoma: These are Cancers of the immune system tissue that are sometimes found in the wall of the Stomach. They account for 4% of Stomach Cancer occurrences.
- Gastrointestinal stromal tumor (GIST) : These are rare tumors that start in very early forms of cells in the wall of the stomach called interstitial cells of Cajal.
- Carcinoid tumor: These are tumors that start in hormone-making cells of the Stomach. Most of these tumors do not spread to other organs. About 3% of Stomach Cancers are carcinoid tumors.
- Other Cancers: Cancer such as squamous cell carcinoma, small cell carcinoma, and leiomyosarcoma, can also start in the stomach, but these Cancers are very rare.
Stomach Cancer Occurrence Rate in India
A recent study conducted by Tata Memorial Centre (TMC) on cancer mortality in India has revealed that Stomach Cancer is the second biggest killer in India. An approximation of 22,200 men and 27,500 women die of Gastric Cancer every year in India. Experts revealed that this high rate of Stomach Cancer is contributed by unhealthy diet and lifestyle.
In many places in India the diet is low in fibre content. Spicy food and lots of non-vegetarian food can cause the chronic inflammation of the stomach lining, which if left untreated can turn cancerous.
Most Stomach (Gastric) cancers do not cause any symptoms until they have spread too far to be cured, but sometimes, we do get symptoms at an early stage.
- Indigestion and stomach discomfort.
- A bloated feeling after eating.
- Mild nausea.
- Loss of appetite.
- Blood in the stool that might or might not be visible to naked eyes.
- Weight loss for no known reason.
- Stomach pain.
- Ascites (build-up of fluid in the abdomen).
- Trouble swallowing.
These symptoms are more likely to be caused by conditions other than Stomach (Gastric) cancer. Still, it’s important to see your doctor right away so the cause can be found and treated, if needed.
The definite causatives of Stomach Cancer are yet under study. However, there is a strong correlation between a diet high in smoked and salted foods and Stomach Cancer.
Throughout these years of analysis and diagnosis of the disease certain risk factors have been identified that highly increases the probability of the occurrence of the disease. Some of them are discussed below:
- Gender: Stomach Cancer is more common in men than in women.
- Age: The risk of Stomach Cancer increases with increasing age. Most people diagnosed with Stomach Cancer are between their late 60s and 80s.
- Helicobacter pylori (H. pylori) infection: It is a major cause of Stomach Cancer, especially cancers in the lower (distal) part of the stomach. Every one in three Stomach Cancer cases can be attributed to H pylori infection.
- Stomach lymphoma: People who have had a certain type of lymphoma of the stomach known as mucosa-associated lymphoid tissue (MALT) lymphoma have an increased risk of getting adenocarcinoma of the stomach.
- Diet: An increased risk of Stomach Cancer is seen in people with diets that have large amounts of smoked foods, salted fish and meat, and pickled vegetables. On the other hand, eating lots of fresh fruits and vegetables appears to lower the risk of Stomach Cancer.
- Tobacco use: Tobacco usage is the major cancer causative. The rate of Stomach Cancer is almost doubled in smokers.
- Previous stomach surgery: Stomach Cancers are more likely to develop in people who have had part of their stomach removed to treat non-cancerous diseases such as ulcers.
- Hypertrophic Gastropathy: Excess growth of the stomach lining causes large folds in the lining and leads to low levels of stomach acid. This is a rare condition that accounts to Stomach Cancer.
- Familial adenomatous polyposis (FAP): People with this syndrome are at greatly increased risk of getting colorectal cancer and have a slightly increased risk of getting Stomach Cancer.
- Pernicious anemia: Certain cells in the stomach lining normally make a substance called intrinsic factor (IF) that we need to absorb vitamin B12 from foods. People without enough IF may end up with a vitamin B12 deficiency, which affects the body’s ability to make new red blood cells and can cause other problems as well. This condition is called pernicious anemia. Along with anemia (too few red blood cells), people with this disease have an increased risk of Stomach Cancer.
If you have any of the above symptoms, please get yourself checked. It may be noting, but it’s best to be sure!
Stomach Cancer can be prevented to an extent by avoiding the risk factors. One can lower the risk of developing Stomach Cancer by
- Maintaining a healthy weight.
- Eating a balanced, low-fat diet.
- Dietary supplements
- Quitting smoking.
- Exercising regularly.
- Treating Helicobacter pylori infection
- Taking medicines to treat a precancerous condition or to keep cancer from starting.
The stages of adenocarcinoma Stomach Cancer include:
Stage I. At this stage, the tumor is limited to the layer of tissue that lines the inside of the stomach. Cancer cells may also have spread to a limited number of nearby lymph nodes.
Stage II. The cancer at this stage has spread deeper, growing into the muscle layer of the stomach wall. Cancer may also have spread to more of the lymph nodes.
Stage III. At this stage, the cancer may have grown through all the layers of the stomach and spread to nearby structures. Or it may be a smaller cancer that has spread more extensively to the lymph nodes.
Stage IV. This stage indicates that the cancer has spread to distant areas of the body.
Relative survival statistics compare the survival of patients diagnosed with cancer with the survival of people in the general population who are the same age, race, and sex and who have not been diagnosed with cancer. Because survival statistics are based on large groups of people, they cannot be used to predict exactly what will happen to an individual patient. No two patients are entirely alike, and treatment and responses to treatment can vary greatly.
Cancer stage at diagnosis highly determines treatment options and has a strong influence on the length of survival. The earlier Stomach Cancer is caught, the better chance a person has of surviving.
Since people with Stomach Cancer rarely show symptoms in the early stages, the disease is often not diagnosed until it’s more advanced.
However, with the advancement in science and technology a few tests and procedures aids in locating the disease at an early stage. Some of the tests are:
- Physical Examination: The doctor checks the medical history of the patient and extracts the detailed information regarding the signs and symptoms.
- Upper Endoscopy: A thin tube containing a tiny camera is passed down through the throat into the stomach. If any suspicious areas are found, a biopsy is performed.
- Biopsy: It is the removal of a small amount of tissue for examination under a microscope.
- Endoscopic ultrasound: An ultrasound uses sound waves to create a picture of the internal organs. The ultrasound image helps doctors determine the spread of cancer.
- Imaging tests: Imaging tests used to look for Stomach Cancer include computerized tomography (CT) scans, positron emission tomography (PET) and X-ray exam.
- Exploratory surgery: Exploratory surgery is usually done laparoscopically. This means the surgeon makes several small incisions in your abdomen and inserts a special camera that transmits images to a monitor in the operating room.
The main treatments for Stomach Cancer are:
- Removing early-stage tumors from the stomach lining
- Removing a portion of the stomach (subtotal gastrectomy)
- Removing the entire stomach (total gastrectomy)
- Removing lymph nodes to look for cancer
- Surgery to relieve signs and symptoms
- Chemotherapy: Chemotherapy is a drug treatment that uses chemicals to kill cancer cells. Chemotherapy can be given before surgery to help shrink a tumor so that it can be more easily removed. Chemotherapy is also used after surgery to kill any cancer cells that might remain in the body.
- Targeted therapy Targeted therapy uses drugs that attack specific abnormalities within cancer cells. Targeted drugs used to treat Stomach Cancer include:
- Trastuzumab (Herceptin) for Stomach Cancer cells that produce too much HER2.
- Ramucirumab (Cyramza) for advanced Stomach Cancer that hasn't responded to other treatments.
- Imatinib (Gleevec) for a rare form of Stomach Cancer called gastrointestinal stromal tumor.
- Sunitinib (Sutent) for gastrointestinal stromal tumors.
- Regorafenib (Stivarga) for gastrointestinal stromal tumors.
- Radiation therapy: Radiation therapy uses high-powered beams of energy, such as X-rays and protons, to kill cancer cells. Radiation therapy can be used before surgery to shrink a stomach tumor so that it's more easily removed. Radiation therapy can also be used after surgery to kill any cancer cells that might remain around your stomach.
- Immunotherapy : In this procedure, vaccines and medication are used to stimulate the immune system of the body. It boosts the body's natural defenses to fight against cancer. Substances made by the body or in a laboratory are used to improve or restore immune system function. Immunotherapy works in either of the following ways:
- Stops or slows down the growth of cancer cells
- Inhibit cancer from spreading to other parts of the body
- Helps the immune system to destroy cancer cells
This is dependent on te stage the Cancer has reached. However, the Cancer is usually in an advanced stage when it is diagnosed. In such cases, it can be treated, but rarely cured.
If you have any of the symptoms, please do visit the doctor.
If you feel any of the symptoms mentioned in the Symptoms section , you should probably visit a doctor. You can also get your genetic make-up checked to see if you are prone to Stomach (Gastric) cancer or not.