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Cancer symptoms you should never ignore

People of all ages and genders have a tendency to bury their heads in the sand. That's particularly true when it comes to unexplained medical symptoms, especially if they're a bit embarrassing to discuss.

It's vital to be aware of changes to your body: whether that's a lump that's appeared, changes to your bowel habits, or a bloated tummy that you've experienced for weeks. Don't just ignore them and hope they'll go away.

Because where cancer is concerned, 'going away' is not going to happen. More importantly, the earlier you're diagnosed and treated, the less extreme your treatment is likely to be and the better your chances of long-term survival.

Clare Hyde, health information officer at Cancer Research UK, says: "With a long list of possible signs and symptoms it can be hard to remember what might or might not be cancer. That's why we encourage people to know their bodies and what is normal for them. If you do notice a change or something that doesn't seem right - whatever it is - it's important to tell your doctor. It probably won't be cancer but, if it is, catching it early means that treatment is much more likely to be successful, giving you a better chance of beating the disease."

Here are some of the signs it's particularly important to let your doctor know about:

Cancer symptoms you should never ignore

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Blood in your poo

If you've experienced a change in your bowel habit or blood in your poo for more than three weeks, you should see your GP. Looser or more frequent poos are a particular concern. Now, while we all do it, pooing is the last thing most of us want to read about over our breakfast cup of tea. But we ignore possible bowel cancer symptoms at our peril.

If you do have bowel cancer (and it's the second most common cancer killer in the UK), burying your head in the sand is guaranteed not to make it go away. And getting it diagnosed early hugely increases your chance of successful treatment.


Bloating is a common but annoying symptom that usually goes away by itself. We're talking here about persistent bloating - not the kind that comes on after a big meal and settles in an hour or two. If you've been feeling bloated on 12 days or more in the last month, go to your doctor. It's probably nothing serious, but it could be a sign of ovarian cancer. It could also be IBS or premenstrual syndrome, but don't self-diagnose.

Annwen Jones, chief executive of Target Ovarian Cancer, says: "The symptoms of ovarian cancer include persistent bloating, always feeling full, tummy pain, and needing to wee more. If you're experiencing any of these symptoms regularly, and they are not normal for you, it is important that you see your GP."

"It's unlikely that your symptoms are caused by a serious problem, but getting checked out by your GP is important, and will put your mind at rest. Early diagnosis of ovarian cancer makes the disease easier to treat. Our nurse-led Support Line is here for anyone who has questions about ovarian cancer - call 020 7923 5475."

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Coughing and feeling out of breath

Every week I have someone in my surgery worried their persistent cough is due to lung cancer. It almost always isn't, but if your cough doesn't settle or you're coughing up blood or having difficulty breathing, you should always see a doctor.

The National Institute for Health and Care Excellence (NICE) recommends you should be referred for an urgent chest X-ray if you're over 40 and have two or more of these symptoms with no other explanation:

  • Cough

  • Tiredness

  • Shortness of breath

  • Chest pain

  • Weight loss

  • Appetite loss

If you're a smoker (or ex-smoker) over 40 and have just one of these symptoms, you should be referred for an urgent chest X-ray.

Lumps and bumps

Finding a lump in your breast can cause a lot of anxiety. It's unlikely to be breast cancer - there are many other causes of breast lumps - but it's always worth getting checked out.

"There's no right or wrong way to check your breasts - it's about looking and feeling regularly so any changes can be spotted quickly. The sooner breast cancer is diagnosed, the more effective treatment may be," says Samia al Qadhi, chief executive of Breast Cancer Care.

"Being aware of all the signs and symptoms of breast cancer is crucial - it's not just a lump to look out for. Other changes could be a nipple becoming inverted, discharge from one nipple or a change in texture of the skin. While most symptoms won't mean breast cancer, if you notice anything unusual for you get it checked out by your GP."

Similarly, men should check their testicles regularly. If you notice a change in size or weight of a testicle, or any swelling or tender spots, see your doctor. Doctors are used to examining breasts and genitals. So don't be embarrassed. They've honestly seen it all before.

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Bleeding after menopause

Bleeding from anywhere is scary, and vaginal bleeding once you thought 'that sort of thing' had stopped for good can be especially worrying. In fact, there's a good chance your doctor can reassure you - but you do need to get it checked out.

Doctors call postmenopausal bleeding (PMB) any bleeding more than 12 months after a woman's last period if she is over the age of about 50. If you're taking hormone replacement therapy (HRT) you may get regular periods, but check with your GP if you get significant bleeding more than four weeks after you stop HRT.

Every woman worries about cancer, but about 90% who have PMB can be reassured on testing that there's no sinister cause. Your doctor will need to rule out cancer of the womb lining as well as cancer of the cervix. Some women have a polyp - a small, non-cancerous growth from the womb lining. Many others get PMB because of inflammation of the vaginal lining, caused by vaginal dryness after the menopause.

Persistent heartburn

Most people who suffer heartburn, bloating, feeling sick and/or an acid taste in the back of the throat have simple inflammation of the oesophagus (oesophagitis) to blame for their discomfort. Likewise, burning pain in the top of your stomach in the middle, sometimes associated with bloating, nausea and wind, is most commonly down to inflammation of the stomach lining, or gastritis.

But if these symptoms are associated with vomiting after eating, food sticking as you try to swallow it, weight loss, pain in the front or back of the chest as you swallow, or loss of appetite, it's essential to rule out a more sinister cause.

Cancer of the oesophagus affects just over 8,000 people a year in the UK and most of them are over 50. Stomach cancer is less common in the UK than in some other countries. But the number of people affected is rising. Getting a diagnosis and treatment early can make all the difference to your chances of long-term survival.

Changes to a mole

See your doctor if you develop an abnormal patch of skin or a change in appearance of a mole to rule out skin cancer.

Get to know your body and look of the normal moles or marks so that you will know if there has been any change. In particular, if you notice any change in the size, shape or colour of an existing mole, or if a new dark area of skin develops, see your doctor.

Unexplained weight loss

In most cancer cases, other symptoms will be apparent before any weight loss occurs. But occasionally unintentional weight loss is the first symptom patients notice of multiple types of cancer.

Besides cancer, if you've lost a significant amount of weight without meaning to, you should see your doctor who might test you for type 2 diabetes, depression or hyperthyroidism.

If you don't get referred

It's important to remember that if your GP decided you don't need investigating, it will usually be for very good reasons, and they should be happy to explain them to you. If I referred every patient who ever came to see me worried about cancer, I would probably swamp my hospital's entire cancer services single-handedly. I'm often able to reassure patients that their symptoms are due to a minor cause, but that's not always the case. And if I don't hear about your symptoms, that's a conversation we can't have.

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The information on this page is peer reviewed by qualified clinicians.

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