Kidney cancer symptoms are difficult to spot during its early stages, according to the NHS.
Signs of the disease are similar to urinary tract infections or kidney stones, so it could be difficult to recognise the condition for what it really is.
The cancer may only be spotted during tests carried out for another reason.
But, there are some subtle signs that you should see a GP – including loss of appetite.
“Some of these symptoms only occur once the cancer is more advanced and has spread to other parts of the body, such as the bones or lungs,” said the NHS.
“See your GP if you have symptoms of kidney cancer.
“Although it’s unlikely you have cancer, it’s important to get your symptoms checked out.”
Other signs of kidney cancer include unexplained weight loss, finding blood in your urine, and extreme tiredness.
You should also see a doctor if you find a lump or swelling in your side.
Night sweats and a high fever may be mistaken for flu, but combined with other symptoms, it’s worth seeing a GP.
Coughing up blood and having a persistent pain in your lower back could also be signs of kidney cancer.
In men, the cancer can cause veins to become swollen in the testicles.
You could lower your risk of kidney cancer by losing weight, if you’re obese.
People with high blood pressure are more likely to develop the disease, so eating a healthy, balanced diet and cutting back on salt may lower your chances of the cancer.
“Maintaining a healthy weight, a healthy blood pressure and not smoking is the best way to reduce your risk of kidney cancer,” said the NHS.
About 12,500 people are diagnosed with kidney cancer every year in the UK.