According to the World Health Organisation, cancer accounts for about 9.6 million deaths, making it a leading cause of death worldwide. Stomach cancer, or gastric cancer, is one of the most common cancers; in 2018, there were 1.03 million cases and 783,000 deaths in the same year. It is a disease we should be concerned about, especially since it is more prevalent in Asia. In Singapore, stomach cancer is the 6th most common cancer for Singaporean men and 8th for women. This means about 1 in 50 men will develop stomach cancer in their lifetime.
More so, stomach cancer usually does not present any symptoms in its early stages. Even when they are present, many —including doctors— do not immediately suspect stomach cancer as these symptoms are often overlooked for common conditions that affect the stomach, such as acid reflux and gastritis. By the time a diagnosis is confirmed, the cancer would have already progressed to a much advanced stage. Hence, stomach cancer is often dubbed as a ‘silent killer’.
Who is at risk of this cancer, and what can you do for prevention? This article will explain all you need to know.
How does stomach cancer form?
The stomach is part of our digestive system and acts as a food reservoir. It connects the esophagus with the small intestine and aids in digestion. Stomach cancer occurs when cells in the stomach wall grow and divide without stopping. Eventually, these cells form lumps that grow into tumours, causing the cancer to invade deeply into the stomach wall.
What are the signs and symptoms of stomach cancer?
As mentioned, stomach cancer in its early stages does not show any noticeable signs or symptoms. When they do take effect, they include:
- Upper abdominal pain
- Loss of appetite
- Unexplained weight loss
- Constant indigestion and heartburn
- Feeling very bloated after meals
- Trapped wind and frequent burping
- Persistent stomach pain
- Black or bloody stools
As you can see, these symptoms are very similar to other conditions and not very exclusive. It’s therefore important to see a doctor if you experience any of the symptoms above, especially if they are recurring.
Who is at risk of stomach cancer?
You are at a risk of developing stomach cancer if you have:
- Family history of stomach cancer
While most gastric cancers are sporadic, approximately 10% of cases show familial aggregation. Studies reveal that those with a family history of gastric cancer are three times more likely to develop the cancer, which is the highest out of all cancers in adults, with the exception of ovarian cancer.
- A history of Helicobacter Pylori infection
I’ve written a more comprehensive article on Helicobacter Pylori, but essentially those with the Helicobacter Pylori infection are at a higher risk of developing stomach ulcers and cancer. This risk is higher if you are male and over 55.
- Prior history of stomach lymphoma and stomach polyps
Most types of polyps do not increase the risk of stomach cancer, but adenomatous polyps may sometimes develop into cancer.
- Long term chronic gastritis
- A diet high in salty and processed food
- A diet low in fibre
Additionally, males aged 55 or older and individuals who smoke are generally at risk too.
How is stomach cancer diagnosed?
There are a few ways to go about testing for stomach cancer. Usually, I perform a gastroscopy, biopsy and/or diagnostic imaging tests like a CT scan, upper GI series test, PET scan or MRI. A gastroscopy allows me to see the lining of the patient’s esophagus, stomach and upper part of the small intestine. I will also retrieve biopsies (tissue samples) and send them to the lab to check for cancer.
If cancer is detected, diagnostic imaging tests like X-rays are done to confirm the location and extent of the cancer.
How is stomach cancer treated?
Depending on the stage, position and type of the stomach cancer, other factors like the patient’s age and overall health will determine the most suitable type of treatment. The three main types of treatment are surgery (either partial or total gastrectomy), chemotherapy and radiation therapy.
For stomach cancer still in the early stages, where the cancer is still confined to the stomach, surgery is the most important as we want to remove all cancer cells. If the patient is not suitable for surgery, chemotherapy or radiation therapy is put in place to kill cancer cells or prevent them from growing.
In cases where the cancer is too advanced, treatment is administered to relieve symptoms. However, this will not cure the cancer.
How can I prevent stomach cancer?
We cannot control factors like our genetics, but what we can control are our lifestyle habits to reduce the risk of stomach cancer. Here are some small steps you can take:
- Have a diet rich in fresh fruits and vegetables
- Reduce intake of salted, smoked and processed foods
- Stop smoking
- Be aware of your medical history and go for gastroscopy screenings
Unfortunately, because stomach cancer often isn’t picked up till the later stages, the outlook isn’t as good compared to other cancers. From the time of diagnosis, about 42% live for at least a year, 19% live for at least 5 years and 15% live for at least 10 years.
This may appear grim, but we can change the statistics by being aware of the risk factors, living healthier and going for regular screenings.
- Choi, Y. J., & Kim, N. (2016). Gastric cancer and family history. The Korean journal of internal medicine, 31(6), 1042–1053. https://doi.org/10.3904/kjim.2016.147
- Karimi, P., Islami, F., Anandasabapathy, S., Freedman, N. D., & Kamangar, F. (2014). Gastric cancer: descriptive epidemiology, risk factors, screening, and prevention. Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology, 23(5), 700–713. https://doi.org/10.1158/1055-9965.EPI-13-1057