Symptoms of stomach cancer

Stomach cancer can be hard to spot because its symptoms are often mistaken for ordinary digestive problems. This page explains what to look out for and when to see your GP, because catching it early can make all the difference.

Why stomach cancer can be hard to recognise

Stomach cancer can resemble common symptoms like indigestion or reflux, which are easy to dismiss as just ‘one of those things’. Many people self-treat with over-the-counter medications for years.

Most GPs see one case of stomach cancer every 3-5 years. They see many people who have indigestion or reflux, and almost all of them don’t have cancer. Because it is rare, GPs may not think of stomach cancer right away. They’re less likely to suspect it if you’re not the typical stomach cancer patient (older and assigned male at birth).

If your symptoms don’t go away or get worse, keep seeing your GP until you find answers. Because the earlier stomach cancer is found, the easier it is to treat.

General symptoms

Common digestive symptoms can have many different causes. Understanding your symptoms can help you recognise when to ask your doctor about further tests.

If you have any of these general symptoms for more than three weeks, you should visit your GP.

Click the + signs by each heading to reveal more information about each symptom.

Indigestion

What it is
Indigestion, or dyspepsia, is a general term for discomfort after eating. It can include heartburn, acid reflux, bloating, or pain in your upper abdomen.

Why it matters
Most of the time, it’s nothing serious. It can be caused by what you eat, your weight, or pregnancy. But it can be due to conditions that can increase the risk of stomach cancer, like gastritis (inflammation of the stomach lining), ulcers caused by H. pylori infection, or reflux disease (GORD). Indigestion can also be an early sign of stomach cancer.

What it means for you
If indigestion keeps coming back, doesn’t improve or gets worse over time, make an appointment with your GP. Persistent indigestion should always be checked out to make sure nothing important is missed.

Heartburn and acid reflux

What it is
Heartburn is a burning or painful feeling in the chest caused by stomach acid that travels upwards into the oesophagus (food pipe).

Why it matters
It’s common and usually linked to lifestyle factors such as rich, spicy, or acidic foods, overeating, being overweight, pregnancy, smoking, or heavy drinking.

Around one in ten people with ongoing heartburn have GORD (gastro-oesophageal reflux disease), a long-term form of reflux that can damage the junction between the oesophagus and stomach. In some people, GORD can develop into gastro-oesophageal junction cancer.

What it means for you
Heartburn and reflux are among the most common symptoms reported by people later found to have stomach or junction cancer. If your symptoms are frequent or getting worse, talk to your GP, especially if they don’t settle with standard treatments.

Feeling full quickly

What it is
Early satiety means feeling physically full after eating a smaller amount of food than usual. It is the sensation that your stomach can’t take any more food, which is not the same as having a low appetite.

Why it matters
Early fullness can be a sign that your stomach may not be expanding or emptying normally. Rarely, this can be a symptom of stomach cancer.

What it means for you
If you feel full unusually quickly and your eating capacity is dropping over time, tell your GP so the cause can be investigated.

Excessive burping or hiccupping

What it is
Burping (belching) is the regular release of swallowed air or digestive gases. Hiccups are brief spasms of the diaphragm that can occur after eating quickly or drinking fizzy or cold drinks.

Why it matters
Excessive burping can be caused by a hiatus hernia, slow stomach emptying, or previous stomach surgery. In very rare circumstances, it can be caused by stomach cancer.

Hiccups that last more than 2 days can be caused by reflux, medication side effects, or, in rare cases, stomach cancer.

What it means for you
Burping now and then is normal. But if it’s constant, disruptive, or accompanied by other symptoms, see your GP. The same applies if hiccups don’t go away after 2 days.

Nausea and vomiting

What it is
Nausea is the sensation of feeling sick, as though you may vomit. Vomiting is being sick (throwing up).

Why it matters
Nausea and vomiting can be caused by many reasons, such as food poisoning, too much alcohol, disordered eating or even stress. In rare cases, persistent vomiting may be from cancer blocking the top or bottom of the stomach.

What it means for you
If you’re vomiting often, without a known reason or can’t keep food down, see your GP. Blood in vomit or vomit that looks like coffee grounds, always needs urgent attention.

Good to know
A Cambridge University study found that some people diagnosed with stomach or oesophageal cancer described vomiting thick white strands or foamy white vomit. This doesn’t always mean cancer, but it’s worth mentioning to your GP if you notice it.

Pain

What it is
Pain from the stomach is usually felt high up in the abdomen, above the belly button or behind the ribs. It’s sometimes described as a dull, gnawing ache or a hunger-like pain that doesn’t go away after eating.

Why it matters
There aren’t many nerve endings in the stomach itself, so actual stomach pain is less common than people expect. Stomach pain can be from stomach ulcers or gastritis. Rarely, persistent stomach pain may be due to stomach cancer.

What it means for you
If the pain is constant or getting worse, see your GP to rule out serious causes.

'Never ignore' symptoms

These symptoms don’t always mean cancer, but they should never be ignored. They can sometimes point to other serious conditions that need urgent investigation.

Tell your GP about them as soon as possible so the cause can be found and treated.

Unintended weight loss

What it is
Losing weight without trying can be a sign that something isn’t right in your body. Doctors define this as losing 5 per cent or more of your usual body weight over a few weeks or months without meaning to.

What it means for you
If you’ve lost noticeable weight without trying, especially if you have other symptoms, tell your GP. It’s important to find the reason early.

Difficulty swallowing, food getting stuck

What it is
Dysphagia is when food or drink feels like it gets stuck, moves slowly, or needs extra swallows to go down.

What it means for you
If swallowing is becoming harder or more uncomfortable, or you’re struggling to get food or drink down, see your GP straight away for further testing. Dysphagia is a ‘red flag’ symptom which will lead to additional tests, regardless of your age.

Fatigue or breathlessness from anaemia

What it is
Anaemia means you don’t have enough haemoglobin in your red blood cells to carry oxygen around your body. It can make you feel weak, breathless, or exhausted. It can be caused by many things, including bleeding within the stomach.

What it means for you
If you feel unusually exhausted, short of breath with light activity, or notice you look paler than usual, including inside your lower eyelids, on your palms, or nail beds, see your GP for a blood test. Severe anaemia may require treatment, such as iron tablets or blood transfusions, while the cause is investigated.

Lumps in the left side of the neck

What it is
A lump on the left side of your neck, just above the collarbone, can be a swollen lymph node called the supraclavicular node, also known as Virchow’s node. In rare cases, stomach cancer may spread to these nodes, which can sometimes be felt or seen.

What it means for you
If you notice a lump in this area, see your GP. The node may feel painless, hard or fixed, and it’s important to have it checked to find the cause.

Black, tarry stool (poo)

What it is
Bleeding from the stomach can make stool look black, sticky, and tar-like. This is because blood has been partially digested as it passes through the intestines.

What it means for you
Always tell your GP if you notice black, tarry stool or any blood in your poo. You may be referred for a colonoscopy to find the source. If you have other symptoms on this page, ask whether you can also be referred for an endoscopy (gastroscopy).

Symptoms requiring urgent attention

If you experience any of these symptoms, always seek medical attention promptly.

Vomiting blood

Jaundice

Ascites

Intestinal blockage

An intestinal blockage happens when food and gas can’t move through the bowel. It causes severe cramping pain, vomiting, and swelling. If the blockage is partial, you might still pass small ribbon-like stools or a little diarrhoea but still feel blocked.

Action: A partial blockage is serious, and a complete blockage is a medical emergency. Call 111 immediately or go straight to A&E.

When to see your GP

If you’ve had any of the general symptoms on this page most days for more than three weeks, book a GP appointment.
If you have any of the ‘never ignore’ symptoms, see your GP as soon as possible.
For urgent symptoms, or if you are in any doubt, call 111.

About our information

The information on this page has been written, revised and edited by Stomach Cancer UK’s editorial team. All material on this page is provided for general information only.

SCUK

Editorial team Author

Reviewed: 30 November 2025

Next review: 30 November 2028

This material is currently under review

References

References for this page are available on request