Symptoms of stomach cancer
Cancer Research UK
Symptoms of stomach cancer include difficulty swallowing, weight loss and indigestion (dyspepsia).
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The most common symptoms of stomach cancer include:

difficulty swallowing (dysphagia)

unexplained weight loss

tummy pain

indigestion (dyspepsia) that doesn't go away

feeling full after eating small amounts

a loss of appetite

feeling or being sick

dark poo

tiredness due to low levels of red blood cells (anaemia)

Some people might not have any symptoms of their anaemia. You might have a blood test for something else, which picks up on this.

Symptoms of early stomach cancer can be similar to the symptoms of other conditions, such as stomach ulcers.

Difficulty swallowing (dysphagia)

You might feel pain or a burning sensation when you swallow, or your food may stick in your throat or chest. Other conditions could cause these symptoms, but it is important to get these checked by your doctor.

Weight loss

This is weight loss when you are not trying to lose weight. This could be due to:

a loss of appetite

feeling full after eating small amounts

Pain

You may have pain in your tummy (upper abdomen) or behind your breastbone (sternum).

Indigestion (dyspepsia) that doesn't go away and burping

You can get indigestion when acid from the stomach goes back up (refluxes) into the food pipe (oesophagus). Or you can get it if you have irritation in your stomach. Symptoms include:

being bloated

feeling or being sick

pain or discomfort in your chest or tummy

a burning feeling in your chest (heartburn) after eating

Remember, indigestion is common and is not usually caused by cancer. Indigestion and heartburn can be very painful, even if nothing is seriously wrong. See your doctor if these symptoms don't go away. Also talk to your doctor if anything you take for indigestion stops working.

Feeling and being sick

Stomach cancer can cause a blockage in the stomach. This stops food from passing through your digestive system and can make you feel or be sick.

Rarely, there is blood in the vomit. This might be bright red, which means it is fresh bleeding. Or it may look dark brown, like used coffee grounds, if the blood has been in the stomach for a while.

Dark poo (blood in your stool)

Early and advanced stomach cancer can bleed into the stomach. Over time this reduces the number of red blood cells in your blood (anaemia).

Your poo may be darker – almost black – if your stomach is bleeding. Your poo can also be darker if you're taking iron tablets.

Feeling tired and breathless

This can be because you have a reduced number of red blood cells (anaemia).