stomach cancer

Stomach Cancer 101: Symptoms, Stages, Causes, Treatment & Prevention

Learn all about stomach cancer, also known as gastric cancer, including its symptoms, stages, treatment, types, and prevention.

by Elaine Francis, R.N.

What is Stomach Cancer?

Stomach cancer may also be referred to as gastric cancer – it is a cancer of the cells in the stomach. Cancer happens when, for some reason, cells begin to grow in an uncontrolled, harmful way. Cancers can affect almost any part of the body, and can spread from their original source to other places around the body. Stomach cancer usually begins as a small nodule in the tissues of the stomach, where abnormal cells begin to reproduce and spread.

Stomach cancers are often slow-growing, and may have been developing for some time before any significant symptoms appear.

Stomach cancer is the 5th most common cancer in the world, and the 6th most deadly cancer in Singapore. There were 1160 cases diagnosed in 2018, according to the last annual report of the Singapore Cancer Registry. Our risk of developing stomach cancer increases as we get older, and it is more common in men than women.

Types of Stomach Cancer

Different types of stomach cancer are described according to the way they present and grow.


Most – at least 90% – of stomach cancers are adenocarcinomas. This is a kind of cancer that develops from the cells in the lining of the stomach. There are two main types of adenocarcinoma in stomach cancer – it can be either intestinal or diffuse. Intestinal gastric adenocarcinoma is the most common type of stomach cancer, and usually begins as gastritis, and is closely linked to lifestyle factors and helicobacter pylori infection – a type of bacteria that causes stomach irritation and ulcers that can develop into cancer. Intestinal adenocarcinoma has a good prognosis, partly because it usually causes symptoms early on in the disease. Diffuse adenocarcinoma is harder to diagnose and treat, and has a worse prognosis than intestinal adenocarcinoma.

Rarer types of stomach cancer include:

Gastrointestinal Stromal Tumours

These are cancerous tumours that can develop in any part of the digestive system, in cells called stromal cells which form part of the connective tissue of the body.


These are cancers that affect the immune system. They spread around the body but usually start in one particular place; occasionally the stomach.

Neuroendocrine Tumours

These are a type of cancer that can start in various parts of the body, sometimes the stomach, and which affect the cells which make and release hormones.

Signs and Symptoms of Stomach Cancer

Some of the symptoms that could – but do not necessarily – indicate stomach cancer include:

  • Heartburn, acid reflux, frequent belching, and indigestion – these symptoms are associated with stomach cancer, but are also symptoms of other conditions, many of which are much more common than stomach cancer.
  • Swallowing problems – especially a feeling of a lump in the throat. This is also known as dysphagia.
  • Frequent vomiting, especially just after eating.
  • Feeling constantly full, or even being able to feel a lump in the stomach.
  • Unexplained and unintended weight loss.
  • Feeling generally unwell, with a lack of energy and appetite.

It’s always worrying if you have any symptoms that could be linked to a form of cancer, but most of the symptoms of stomach cancer overlap with other conditions – it’s important to have proper investigations and a professional diagnosis.

Stomach Cancer Causes & Risk Factors

Some people are more likely to get stomach cancer than others; there are a number of genetic, lifestyle, and environmental factors which seem to contribute to this. Knowing the risk factors for stomach cancer can help us reduce our own risk where possible.

Helicobacter Pylori Infection

Many stomach cancers are directly linked to an infection of helicobacter pylori (H. pylori). H. pylori is a type of bacteria that lives in the stomach lining and can cause ulcers. Helicobacter pylori is easily treated so early diagnosis and treatment of H. pylori infections and gastric ulcers can actually stop some types of stomach cancer from ever developing. H. pylori infection is the strongest risk factor for stomach cancer.

Poor Diet

In particular, eating lots of smoked or pickled foods increases the odds of getting a gastric adenocarcinoma. A diet rich in fresh vegetables is associated with a lower risk of cancer.


Smoking is linked to an increased risk of a wide variety of different cancers, and stomach cancer is no exception. Stopping smoking is one of the best things anyone can do to improve their health and reduce their risk of serious diseases.

Alcohol Excess

Having a high alcohol intake is linked with a higher risk of stomach cancer.

Risk factors we don’t have control over include having a family history of stomach cancer, being male, and getting older.


Homage Care Professionals go through extensive training and are equipped to provide care for people diagnosed with different conditions, recovering from injury or surgery and medical escort services.

Other services include:

  • Wound Care
  • Stoma Bag Care
  • Feeding Tube Care
  • Other Caregiving Needs

Our Care Advisors can come up with a personalised care plan for your loved ones. Simply fill up this form to schedule a free consultation.

Stomach Cancer Stages

Cancers are measured in ‘stages’, which describe the extent and severity of the cancer in the body. Some cancers, such as lymphomas that start in the stomach, or adenocarcinomas which are situated high in the stomach where the stomach meets the oesophagus are described and treated differently, and follow a different development and management pattern. The stages of stomach cancers are, broadly:

Stage 1 Stomach Cancer

At the earliest stage of stomach cancer, the cancer only exists in a small number of cells in the stomach, and is contained to one area, but may involve more than one of the layers of the stomach lining. If stomach cancer is identified at stage 1 and rapid treatment is given, the prognosis is very good. Sometimes, pre-cancerous or very discreet cancerous cells may be found and treated, and they may be referred to as ‘stage 0 cancer’

Stage 2 Stomach Cancer

This is where the cancer has spread to some of the deeper layers of the stomach tissues, and may have spread to some nearby lymph nodes.

Stage 3 Stomach Cancer

The cancer may have spread to more lymph nodes, and have spread through the full thickness of the stomach wall. It may be spreading into nearby tissues and organs.

Stage 4 Stomach Cancer

At stage 4, a cancer has spread to distant parts of the body. This is known as metastasis. Different types of cancer have different patterns of spread, but metastases can commonly affect the brain, bones, liver or lungs.

Diagnosing Stomach Cancer

There are several more common conditions which could cause some or all of the symptoms associated with stomach cancer, so it’s important to get investigated and treated by doctors as soon as you notice problematic symptoms. The sooner a condition is identified and managed, the better the outcome.

A diagnosis of stomach cancer might first be suspected from symptoms alone, which will prompt further investigations. This will involve blood tests, which look for tumour markers and other abnormalities, and an endoscopy.

An endoscopy is any procedure where a tube is used to look inside the body – using a fine tube to look down the throat into the stomach is called a gastroscopy. To prepare for a gastroscopy, you will usually have to avoid food and drink for a number of hours before the procedure. You will be awake during the procedure, and will be asked to swallow as a doctor or specialist nurse passes a tube down your throat. It can feel unpleasant, but is a very safe procedure. The doctor may use a spray to numb the back of your throat, or may offer a light sedative to help you feel relaxed throughout. The endoscope allows the doctor to carefully examine the inside of the oesophagus, stomach, and the top part of the small intestine. The instrument can be used to take tissue samples, and even to remove cancerous cells if they’re confined to small areas. The procedure is usually done as a day case.

Further tests, such as CT scans and MRIs can help guide a diagnosis and treatment plan. They may be referred to as ‘staging’ scans, as they’re used to see if and how far the cancer has spread.

Stomach Cancer Treatment

The kind of treatment used for stomach cancer depends on the exact position and type of the cancer, and whether or not – and how far – it has spread. The treatment may also depend on a person’s health, and some other medical conditions may limit the amount of treatment that can be offered or that would be appropriate. If a cancer cannot be cured, treatment may still help to control the symptoms and slow the progression.


In the early stages, some cancers may be able to be fully removed. Surgeons may have to remove part or all of the stomach, and possibly some parts of surrounding tissues or organs. In later stages, surgery can help relieve symptoms by removing any parts of tumours that are restricting normal swallowing and digestion, but might not be a curative treatment.


Chemotherapy may be given before surgery to try and shrink a tumour, and after surgery to target any remaining cancerous cells. Chemotherapy can be used alongside other treatments like radiotherapy to help treat or control cancer.


Radiotherapy uses a kind of radiation targeted to kill cancer cells. It can be used alongside other therapies to treat or control cancer.

Targeted cancer therapies are an area of continual research, and therapies are improving all the time.

Stomach Cancer Prevention

Not all forms of stomach cancer can be predicted or prevented, but the best thing you can do to prevent any form of cancer, and especially stomach cancer, is to follow a healthy diet. A diet that is high in fruit, vegetables, and whole grains can help prevent some forms of stomach cancer, as well as a wide range of other cancers and serious diseases. Maintaining a healthy weight and following a healthy lifestyle are some of the best things any of us can do to stay health.

The basics of healthy living are well known – exercise and a good diet, a low alcohol intake and no smoking are simple ways to stay healthy. It’s not always easy to stick to this kind of healthy lifestyle, but support from healthcare providers can help; people are much more likely to give up smoking for good with some professional support. It’s always okay to ask your GP for advice on getting healthier.  

Living with Stomach Cancer

Any serious diagnosis can feel overwhelming, and it’s important to know you’re not alone if you or someone close to you is diagnosed with cancer. Caught in the early stages, stomach cancer can often be treated with good results. Cancers that have spread to other parts of the body generally have a worse prognosis, and some people dealing with stomach cancer will have been told that their condition is terminal. Cancer treatments can be difficult, both physically and emotionally, and everyday life has to be adapted around treatment and symptoms.

Friends, family, and professionals who help look after people with cancer can all lend invaluable support, and there’s no need to go through this alone. Cancer specialists are just one part of a team of professionals to offer support for any of the physical and emotional challenges that come with a cancer diagnosis and treatment.

The physical effects of cancer and cancer treatments can be difficult, and having practical support can be invaluable. Dedicated carers can help lift the burden of living with cancer, and acting as escort for medical appointments.

Stomach Cancer Support Groups in Singapore

No one should have to face cancer alone, and whether you or someone you love is affected by cancer, it’s always okay to ask for help.

There are many local, national, and international organisations which offer support to anyone experiencing cancer, survivors of cancer and anyone affected.

  • The Singapore Cancer Society has a number of support groups for people affected by cancer, run by and for cancer sufferers and their families.
  • CanHOPE is a not-for-profit cancer counselling and support service.
  • The National University Cancer Institute Singapore have a number of programmes and events to help cancer sufferers and survivors with practical support.

Aside from the ones mentioned above, Homage provides caregiving services for you and your loved ones at every stage. Our trained care professionals are able to provide companionship, nursing care, night caregiving, home therapy and more, to keep your loved ones active and engaged. 

Provide the best care to your loved one today!  Fill up the form below for a free consultation with our Care Advisory team. 

Fill out the form below and our Care Advisors will get back to you with care information you need.

In the event that we will need to contact you, please look out for our outgoing number +65 3129 6885.

This number may be flagged as “potential fraud” but please be assured this is the official Homage number that we use to reach out to our customers.

  • ✓ Valid number ✕ Invalid number

  • By submitting this form, you agree that Homage may collect and use your personal data, which you have provided in this form, in accordance with Homage’s Data Protection Policy
  • Hidden

  • This field is for validation purposes and should be left unchanged.

  1. National Registry of Diseases Office (2021) Sinagpore Cancer Registry Annual Report 2018.
  2. Hu, B., El Hajj, N., Sittler, S., Lammert, N., Barnes, R., & Meloni-Ehrig, A. (2012). Gastric cancer: Classification, histology and application of molecular pathology. Journal of gastrointestinal oncology, 3(3), 251–261.
  3. Brenner H., Rothenbacher D., Arndt V. (2009) Epidemiology of Stomach Cancer. In: Verma M. (eds) Cancer Epidemiology. Methods in Molecular Biology, vol 472. Humana Press.
  4. Wroblewski, L. E., Peek, R. M., Jr, & Wilson, K. T. (2010). Helicobacter pylori and gastric cancer: factors that modulate disease risk. Clinical microbiology reviews, 23(4), 713–739.
  5. Praud, D., Rota, M., Pelucchi, C., Bertuccio, P., Rosso, T., Galeone, C., … & La Vecchia, C. (2018). Cigarette smoking and gastric cancer in the Stomach Cancer Pooling (StoP) Project. European Journal of Cancer Prevention, 27(2), 124-133.
  6. Tsugane, S., & Sasazuki, S. (2007). Diet and the risk of gastric cancer: review of epidemiological evidence. Gastric cancer : official journal of the International Gastric Cancer Association and the Japanese Gastric Cancer Association, 10(2), 75–83.
  7. Ma, K., Baloch, Z., He, T. T., & Xia, X. (2017). Alcohol Consumption and Gastric Cancer Risk: A Meta-Analysis. Medical science monitor : international medical journal of experimental and clinical research, 23, 238–246.
  8. Roberts, P. J., & Eisenberg, B. (2002). Clinical presentation of gastrointestinal stromal tumors and treatment of operable disease. European journal of cancer, 38, S37-S38.
About the Writer
Elaine Francis, R.N.
Elaine Francis is a registered nurse with 17 years’ experience in healthcare. She turned to writing to follow her passion for realistic medical communication. She loves translating medical jargon into accessible language for the people who need to understand it most. When she’s not writing or working on a busy cardiology unit, she spends her time telling her children to hurry up.
Make Home Care Personal To Your Loved One

Make Home Care Personal To Your Loved One

Get started with a free consultation today, and learn why thousands of Singaporeans trust Homage to deliver the best care in their homes.

Get Care Now