What is cancer? Symptoms, causes and prevention

Cancer is a serious life-threatening condition that comes in various stages and forms. In fact, there are over 200 different types of cancer, and the stages vary depending on how advanced someone’s cancer is. There are treatments available, however, there are side effects and treatment effectiveness typically depends on how early cancer is detected. Unfortunately, 1 in 2 people will develop some form of cancer in their lifetime, but research is ongoing to help cure as many people as possible. This guide will explore cancer, highlighting the causes, symptoms and prevention and treatments available.

What is cancer?

Cancer is a condition causing cells to grow and reproduce uncontrollably in the body. These cells, called cancerous cells, destroy healthy cells and tissues (such as organs) as they develop and continue to spread. The process of spreading to different parts of the body, from where the cancer began originally, is referred to as metastasis. Early detection is key as cancer can cause severe symptoms and be life-threatening. It is important to note that not all tumours spread to other parts of the body. Those that do not spread to other parts of the body are called “benign”.

Even though there are over 200 types of cancers, some are more common than others. The most common types of cancer include skin, breast, prostate, lung and bowel.

What are the symptoms of cancer?

Knowing how to spot the early signs of cancer can be life-saving as early detection usually makes treatment more effective. Some signs of cancer include the following:

  • Lumps: these can be benign growth or cancerous. You should consult your GP if you can feel a new lump anywhere in your body.
  • Moles: moles that change in colour, size or texture should be checked by your GP as the changes may be caused by skin cancer. This is also the case if one of your moles starts crusting, bleeding or itching.
  • Changes in bowel habits: changes such as persistent diarrhoea and constipation (3 weeks or more), pain in the stomach and/or anus, blood in your stools, or a feeling of not having fully emptied your bowels after a movement could indicate bowel cancer.
  • Coughing, breathlessness and chest pain can be a sign of cancer. It is recommended that you see a GP if you have had a cough for over 3 weeks. Such symptoms can also be caused by smoking and pneumonia.
  • Bloating: bloating that has persisted for over 3 weeks can be a sign of cancer.
  • Unexplained weight loss: unintended loss of weight may be a sign of cancer and should therefore be discussed with your GP.
  • Bleeding: blood in the stools, urine, vomit or that is coughed up can indicate cancer. You should also talk to your GP if you are bleeding in-between periods or after menopause.
  • Sores that don’t heal: A spot or sore that doesn’t heal within a week or so should be checked by your doctor.

It is essential to note that the symptoms abovementioned aren’t necessarily a sign of cancer. However, it is important that you see your GP to assess the cause of such symptoms. It is also worth noting that a lot of cancers do not cause symptoms in the early stages, hence the importance of screening.

What are the causes of cancer?

Cancer is caused by certain changes to the genes that control cell function – particularly those that control the way cells develop, and divide. types of genes affected by cancer include:

  • Tumour suppressor genes. Normally cells repair faults in their genes. If damage is too severe suppressor genes tell the cell to stop growing and dividing. However, if there is a fault in the suppressor gene this may mean that the cell keeps growing and dividing.
  • DNA repair genes, which act to repair damaged DNA in cells
  • Self destruct genes. Some genes tell a cell to die when it has become too old or damaged. If these genes are damaged this process may not happen.

Changes in these genes above are sometimes referred to as ‘drivers of cancer’, and can occur due to:

  • DNA damage: caused by harmful substances such as chemicals in tobacco and UV rays from the sun.
  • Genetics: cancer can be inherited from our parents
  • Errors in cell division

The body generally eliminates cells that have had their DNA damaged before they can become cancerous. However, the body’s ability to eliminate such cells decreases with age, which is why many cancers become more common as people get older.

How to prevent and treat cancer


You can reduce your risk of developing cancer by making some lifestyle changes including:

  • Quitting smoking
  • Remaining active and exercising regularly
  • Eating a healthy, balanced diet low in saturated fats, sugars and preservatives
  • Keeping a healthy BMI
  • Avoiding excessive drinking

Cancer treatment

Treatment will depend on what stage the cancer is at (i.e. how advanced it is). Treatment usually includes one or more of the following:

  • Surgery to remove the tumour
  • Chemotherapy to kill cancer cells with medicines
  • Radiotherapy to kill other cancer cells with high doses of radiation such as X-rays

Treatment can be incredibly draining for the body, as it can affect blood circulation, as well as the lymphatic, immune and hormone systems. The good news is that many cancers can be treated effectively leading to a cure or increased length and quality of life.

How can I get tested for cancer?

At a clinic

Our Cancer Awareness Health Assessments are available for those over 40 years old who would like to assess their risk of certain cancers. We offer a Female Cancer Risk Health Assessment for women, which estimates your risk of bowel, stomach and ovarian cancer. We also offer a Male Cancer risk Health Assessment for men, which includes a bowel, stomach and prostate cancer risk assessment. These plans consist of in-depth, face-to-face health checks with a Health Assessment Specialist, which you can easily book online at one of over 2,000 mobile clinics available nationwide. You will receive a wide array of other key health markers and a detailed results report sent through the post.