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Cancer Awareness GuideGeneral information & support

Cancer warning signs: changes worth discussing with a doctor

The signs below are general and are very often caused by something other than cancer. The point is not to worry, but to know that changes which are new, unexplained or do not go away are worth a conversation with a doctor.

For information only - this is not medical advice. This page cannot tell you whether you have cancer. If you notice a change that worries you, talk to your doctor. If you feel very unwell or think it is an emergency, contact your local emergency services.

Why general signs matter

The US National Cancer Institute (NCI) explains that cancer can cause many symptoms, but that these symptoms are most often caused by illness, injury, benign tumours or other problems. Its advice is simple: if you have symptoms that do not get better after a few weeks, see your doctor so that the cause can be found and treated as early as possible. NCI also points out that cancer often does not cause pain, so it is not a good idea to wait for pain before getting checked (NCI: Symptoms of Cancer).

The NHS in England says the same thing in a different way: most of these symptoms are very common and can be caused by other conditions, having them does not definitely mean you have cancer, but it is important to get checked, because if a symptom is caused by cancer, finding it early may mean it is easier to treat (NHS: Cancer). The World Health Organization (WHO) lists being aware of possible symptoms, and seeking medical advice when something abnormal is noticed, as the first part of early diagnosis (WHO cancer fact sheet).

General changes to get checked

Both NCI and the NHS list general signs that can, in some cases, be linked to cancer. They include:

  • A new lump or swelling anywhere on the body, for example in the neck, armpit, tummy or groin.
  • Weight loss or weight gain for no known reason, or feeling less hungry than usual.
  • Tiredness or fatigue that is severe and lasting, or feeling more tired than usual.
  • Fever or night sweats with no known cause, or a high temperature that lasts or keeps coming back.
  • Unusual bleeding or bruising, such as blood in your urine or stools, or bruising for no known reason.
  • Pain anywhere in the body that is not usual for you.

Changes in particular parts of the body

  • Skin: a new mole or a change in an existing mole, a sore or rash that does not heal or get better, a lump that bleeds or turns scaly, or yellowing of the skin or the whites of the eyes (jaundice).
  • Breast: a lump or firm feeling in the breast or under the arm, nipple changes or discharge, or skin that is itchy, red, scaly, dimpled or puckered.
  • Mouth and throat: problems swallowing, a hoarse voice that does not get better, a mouth ulcer that does not heal, or white or red patches in the mouth.
  • Lungs and breathing: a cough that does not go away or gets worse, shortness of breath that does not get better, or coughing up blood.
  • Digestion and bowel: heartburn or indigestion that keeps coming back or is very painful, bloating that happens often, or a change in bowel habits that does not get better.
  • Bladder: needing to urinate more often or more urgently, trouble or pain when urinating, or blood in the urine.
  • Nervous system: NCI also lists headaches, seizures, and changes in vision or hearing among possible symptoms that should be checked.

This is not a complete list, and different cancers have their own symptoms. The NHS advises seeing a GP for any symptoms or changes that are not normal for you and that you are worried could be cancer.

What happens when you see a doctor

Your doctor will usually ask about your symptoms, your health history and your family history, and may examine you. Depending on what they find, they may arrange tests. In England, the NHS explains that if a GP thinks symptoms could be a sign of cancer, you may get an urgent referral for more tests or to see a specialist. An urgent referral is a way of getting answers quickly - it does not mean you have cancer. NCI notes that there is no single test that can diagnose cancer, and a biopsy is often the only way to know for sure. Our guide to how cancer is diagnosed explains the main tests in plain language.

Making the most of the appointment

  • Write down what you have noticed, when it started, and whether it is getting better, worse or staying the same.
  • Note anything that makes it better or worse, and any medicines or supplements you take.
  • Mention any family history of cancer - see is cancer hereditary? for why this can matter.
  • Take a list of questions with you. Our questions to ask your doctor page has examples.
  • If things do not improve, or new symptoms appear, go back. It is reasonable to ask for a review.

Symptoms and screening are different

Screening tests are for people who do not have symptoms. If you have a symptom, do not wait for a screening invitation, and do not rely on a recent normal screening result - see your doctor. You can read more in cancer screening explained and reducing cancer risk.

Important: these signs are common and usually not caused by cancer. Only a doctor can assess them. If you notice a persistent or unexplained change, book an appointment - finding the cause early is sensible, whatever it turns out to be.

Sources

Last reviewed: 16 October 2026.

Common questions

I have one of these signs - do I have cancer?

Not necessarily. NCI and the NHS both say these symptoms are most often caused by other conditions. Only a doctor can tell, so please book an appointment rather than relying on any website.

How long should I wait before seeing a doctor?

NCI advises seeing a doctor if symptoms do not get better after a few weeks. If a symptom is severe, getting worse quickly or worrying you, do not wait - contact a doctor sooner.

Does cancer always cause pain?

No. NCI notes that cancer often does not cause pain, so it is best not to wait for pain before getting a lasting change checked.

What is an urgent referral?

In England, the NHS explains that a GP may refer you urgently for tests or to a specialist if symptoms could be a sign of cancer. It is a way of getting answers quickly and does not mean you have cancer.