Cancer Warning Signs You Should Get Checked

Most lumps, coughs and aches are not cancer. A small number are, and cancer found early usually responds better to treatment. This is a short list of the changes worth a doctor's appointment, not because they mean cancer, but because they should not be ignored.

Why get checked at all?

WHO reports that cancer caused nearly 10 million deaths in 2024, close to one in six deaths worldwide, and that when cancer is found early it is more likely to respond to treatment, giving a better chance of survival with less suffering. The NHS puts it simply: if your symptoms are caused by cancer, finding it early may make it easier to treat.

Which general changes are worth checking?

The NHS lists these as possible cancer symptoms anywhere in the body:

• A new lump or swelling anywhere on your body
• Losing weight without trying, or losing your appetite
• Feeling unusually tired for no clear reason
• Unusual bruising or bleeding, such as bleeding from your bottom, blood in your urine, or vomiting blood
• Heavy sweating, especially at night, or a high temperature that keeps coming back
• Pain with no obvious cause
• Passing urine more often, more urgently, or with pain

What about changes in one part of the body?

Skin

• A new mole, or a mole that changes
• A sore or rash that does not heal
• Yellowing of the skin or the whites of the eyes

Mouth and throat

• A mouth ulcer lasting more than three weeks
• A red or white patch inside the mouth
• Difficulty swallowing
• A hoarse voice that does not settle

Chest and breathing

• A cough that will not go away, or is getting worse
• Coughing up blood
• Becoming short of breath

Digestion

• Heartburn that is severe or getting worse
• Bloating that does not go away
• A lasting change in your bowel habits

Genital and urinary

• Unusual vaginal bleeding or discharge
• Blood in semen
• New problems getting an erection

Does having these symptoms mean I have cancer?

Almost certainly not. The NHS states clearly that most of these symptoms are very common and can be caused by other conditions, and that having them does not mean you have cancer. Infections, ulcers, piles, acid reflux and hormone changes explain far more of these symptoms than cancer does. The point of getting checked is to find out, and usually to stop worrying.

What lowers my risk in the first place?

WHO estimates that about 38% of cancers can currently be prevented, and that around a quarter of cancer deaths are linked to tobacco use, alcohol, high body weight, low fruit and vegetable intake and physical inactivity. In low- and lower-middle-income countries, around 30% of cancer cases are linked to infections such as HPV and hepatitis, which is why those vaccines matter. The NHS lists stopping smoking, keeping a healthy weight, limiting alcohol, eating a balanced diet, being physically active, protecting your skin from the sun, and having the HPV and hepatitis B vaccines as ways to lower your risk.

When to see a doctor

Book an appointment if any of the changes above does not clear up, keeps coming back, or is getting worse. The NHS specifically advises seeing a doctor for a mouth ulcer that lasts more than three weeks, and for any symptom that is not normal for you and that worries you. Go sooner if you notice blood where there should not be blood, or unexplained weight loss. A dentist can also check mouth symptoms.

Do not wait for a symptom to become painful before you have it looked at, and go back if it was checked once and has since changed. For heavy or uncontrolled bleeding, vomiting blood, sudden severe pain or sudden difficulty breathing, call Rescue 1122 where available, or go to the nearest hospital emergency department.