In Asia, stomach cancer is the second-most common cancer in men and third-most common in women.
Stomach cancer also referred to as gastric cancer, is a build-up of abnormal cells in the stomach, which is a part of the digestive system and found in the upper abdomen. This usually occurs when the cells change or stop behaving normally. These changes can form masses, tumors or lumps which can either be malignant (cancerous) or benign (non-cancerous). Malignant tumors have a high risk of metastasizing, which means they can spread to other organs/parts of the body.
There are 5 different parts to the stomach where cancer can occur, causing different symptoms and often require different treatments.
There are several types of stomach cancer:
- Adenocarcinoma – 90-95% of stomach cancer cases are diagnosed as adenocarcinomas. This cancer develops from the cells found in the inner lining of the stomach, known as the mucosa.
- Lymphoma – Around 4% of stomach cancers are diagnosed as lymphoma. The cancer forms in the lymphatic tissue which can be found in the stomach wall. Lymphatic tissue is responsible for fighting infections and draining fluid and contains cells called lymphocytes.
- Gastrointestinal Stromal Tumor (GIST) – These are very rare tumors that form in the muscle and connective tissue of the stomach wall. In most cases these tumors are benign. They can also be found in other parts of the digestive system.
- Neuroendocrine tumors – These tumors are also very rare and grow from the hormones secreted by enteroendocrine cells in the digestive tract which includes the stomach, pancreas, and small intestine.
Risk Factors & Causes
There are various causes and risk factors that can increase the chances of stomach cancer. These include:
- Medical Conditions – These could be infections like H. pylori infection in the stomach, which is very common in India. Intestinal metaplasia is when cells line the stomach instead of the intestine line. Peptic stomach ulcers, stomach polyps, or chronic atrophic gastritis or long term inflammation which causes the stomach lining to become narrow.
- Smoking – It is no secret that smoking can lead to a multitude of problems and is one of the leading causes of cancer.
- Family History – Doctors will often ask if any close relatives have had stomach cancer as this can increase the risk as well.
- Diet – There are many ingredients which can cause stomach cancer, especially if you consume a large amount. These foods include salt, red meat, and refined grains.
- Gender -Stomach cancer is more common in men than in women.
- Surgical Procedures – Sometimes, stomach cancer can occur many years post some surgeries involving the stomach, such as ulcer treatment.
Symptoms can vary depending on the location of the tumor, type of stomach cancer and at which stage it is diagnosed. Unfortunately, stomach cancer can develop very slowly and some symptoms do not appear until it has reached a later stage.
At an early stage, symptoms can include:
- Feeling full quickly and bloated after meals
- Difficulty in swallowing
- Frequent burping
- Heartburn and indigestion
- Stomach pain
- Trapped wind
- Traces of blood after vomiting
Advanced stomach cancer can present the following symptoms:
- Feeling tired or weak
- Fluid buildup in the stomach which can feel lumpy
- Dark stool containing blood
- Weight loss
- Loss of appetite
Although many symptoms can be related to other conditions, it is important to consult your doctor especially if you find it hard to swallow, there are signs of blood in your stool and if any other symptoms continue to persist.
Diagnosing Stomach Cancer
During your consultation with the doctor, they will ask about your symptoms, family history, and your lifestyle, like smoking and what your diet consists of. They will follow with a physical examination to see if they can feel for any unusual growths or tenderness around the abdomen.
You may also have to provide a blood sample that can identify certain indicators of cancer.
There are different diagnostic methods:
Upper Endoscopy: This procedure involves using an endoscope, an optical tubular instrument used to look inside the stomach. The esophagus, stomach, duodenum (first part of the small intestine) are usually examined.
If there are any unusual findings, the doctor will take a small tissue sample of the growth called a biopsy which will then be sent for analysis.
CT Scan: A CT Scan produces a detailed image of your abdomen at various angles. A dye may be required, which can be swallowed or injected, to help produce clearer images.
X-Ray: Barium is a liquid that is consumed orally and lines the esophagus and stomach. This helps spot any abnormalities during an X-ray taken by a radiologist.
Endoscopic Ultrasound (EUS): An ultrasound involves using a wand-shaped probe to produce images of different organs through the skin. The process involves sound waves detecting echoes internally and then producing black and white images.
An endoscopic ultrasound will happen when the patient is sedated as the wand, with a small transducer on the tip, is passed through the throat into the stomach. This allows the doctor to examine the stomach wall and its different layers and other structures where cancer can commonly appear.
An EUS can often detect the cancer stage and produces clearer images compared to a normal ultrasound.
Therapies Used to Treat Stomach Cancer
What is Chemotherapy?
Chemotherapy uses anti-cancer drugs to stop cancer cells from reproducing and dividing by targeting the enzymes and hormones considered the “food source” for cancer cells to grow.
Chemo is given to shrink the tumor before or after surgery, to slow the progression of the disease, and/or to prevent a recurrence.
It is an invasive treatment given orally, topically or intravenously (injection or infusion). The side-effects can be adverse, including sickness, fatigue, hair loss and more, depending on the type of treatment.
What is Radiation Therapy?
Radiation is similar to chemo in terms of why it is given to patients at different stages. It involves a machine that produces radiation to target specific areas of the body. Another approach to giving radiation involves giving a radioactive substance inside the body, permanently or temporarily.
Side effects depend on the area of treatment and dosage. They can include fatigue, skin changes, hair loss, and diarrhea.
Treatment at Different Stages of Stomach Cancer
Cancer detected early on can be treated with surgery. At this stage, the cancer is confined to the inner lining of the stomach and has not spread deeper into other layers. Surgery can either be a subtotal gastrectomy which involves removing part of the stomach or a total gastrectomy which removes the whole stomach.
Smaller cancer growths detected early can be removed using an endoscope which is passed through the throat into the stomach. This is called an endoscopic resection.
Stage 1 is divided into 2 sub-stages and diagnosed depending on the location of cancer:
Stage 1A: The cancer is commonly removed with either a subtotal or total gastrectomy, similar to Stage 0, and some lymph nodes may also be removed. No further treatment is usually required post-surgery as the cancer is limited to the inner lining.
Stage 1B: This stage means the cancer is in the stomach lining and also in the nearby lymph nodes. This can be treated with a combination of surgery and therapies which include chemotherapy (chemo), radiation therapy, or chemo and radiation (chemoradiation) therapy.
Therapy may be given before surgery to try and shrink the cancer, making it easier to remove, or post-surgery to prevent the chances of the cancer spreading.
The treatment for Stage 2 is similar to that of Stage 1B, but also involves removing the omentum, which is the fatty tissue covering the abdomen, as well as, part of or the whole stomach and nearby lymph nodes.
Chemo or chemoradiation will be given before or after surgery.
Patients who are not able to withstand surgery are given chemo or chemoradiation to shrink and treat cancer.
Cancer can be more aggressive in this stage so it can either be cured or controlled to help relieve symptoms and stop spreading to other organs.
Patients who undergo surgery will be given chemo or chemoradiation before and after surgery to help shrink the cancer and stop it from spreading. Patients who do not receive therapy before surgery is often treated with chemoradiation post-surgery.
At this stage, the cancer is more advanced, with it having spread to distant organs, and it can be difficult to cure. Surgeries and therapies are used in combination to help control the symptoms.
Surgeries can involve:
- Total or Subtotal Gastrectomies
- Gastric Bypass which means dividing the stomach into 2 parts and connecting them with the small intestine to prevent any blockages or obstructions
- Laser Endoscopy which involves passing an endoscope with a laser beam attached to the end, down the throat to the stomach, to destroy most of the tumor to stop further obstruction
Chemo and radiation therapies can often shrink cancer to relieve symptoms for the patient. Targeted therapy can also be helpful which uses targeted therapy drugs to interfere with cell growth. The drug given depends on the type of tumor.
Although it is difficult to cure stomach cancer at this advanced stage, treatment is given to help reduce symptoms, like pain and bleeding.
Recurrent cancer means cancer has come back after treatment. The treatment decided for recurrent cancer depends on the location of cancer, the initial treatment given and the patient’s overall health.
Questions to Ask Your Doctor
Any cancer diagnosis can be a difficult time for the patient and their families. It is important to ask the right questions so you understand treatment options, the type of cancer you have and what to expect, to better prepare you for the journey ahead.
Once you have a diagnosis, you ask your doctor:
- What type of stomach cancer do I have
- What stage is my cancer
- What tests will need to be done
- How much experience do you have with treating this type of cancer
- What is my prognosis
Regarding your treatment options or during treatment, make sure you ask your doctor:
- What are my treatment options
- Which one is recommended and why
- How long will the treatment go on for
- How will I know the treatment is working
- What are the side effects
- How will this affect my daily life
- What foods should I avoid
Pos-treatment you can ask your doctor:
- What do I do if the treatment doesn’t work
- How many times should I schedule a follow-up
- How will I know if cancer has come back
- What symptoms should I be aware of
These are just some suggestions, but be sure to write down any questions you want to ask your doctor. There can be a lot of information thrown at you and it can be hard to understand. But don’t worry, your doctor is here to help you through it. It is important to have the right support system in place as well.