Cancer is a condition where cells in a specific part of theÂ body grow and reproduce uncontrollably. The cancerous cells can invade and destroy surrounding healthy tissue, including organs.
Cancer sometimes begins in one part of the body before spreading to other areas. This process is known as metastasis.
1 in 2 people will develop some form of cancer during their lifetime. In the UK, the 4 most common types of cancer are:
There areÂ more thanÂ 200 different types of cancer, andÂ each is diagnosed and treated in a particular way. You can findÂ links on this page toÂ information about other types of cancer.
Spotting signs of cancer
Changes to your body's normal processes or unusual, unexplained symptoms can sometimes be an earlyÂ sign of cancer.
Symptoms that need to be checked by a doctor include:
- a lump that suddenlyÂ appears on your body
- unexplained bleeding
- changes to your bowel habits
But in many casesÂ your symptomsÂ will not be related to cancer and will be caused by other, non-cancerous health conditions.
Read more about theÂ signs and symptoms of cancer.
Reducing your risk of cancer
Making some simple changes to your lifestyle can significantly reduce your risk of developing cancer.
The Macmillan Cancer Support website has more information about how a healthy lifestyle can helpÂ reduce your chances of developing cancer.
Surgery is the first treatment to try for most types of cancer, as solid tumours can usually be surgically removed.
2 otherÂ commonly used treatment methods are:
- chemotherapyÂ â powerful cancer-killing medicines
- radiotherapyÂ â the controlled use of high-energy X-rays
Accurately diagnosing cancer can take weeks orÂ months. As cancer often develops slowly over several years, waiting forÂ a few weeks will not usually impact onÂ the effectiveness of treatment.
The National Institute for Health and Care Excellence (NICE) has produced referral guidelines for suspected cancer.
YouÂ should not have to wait more than 2 weeks to see a specialist if your GP suspects you have cancer and urgently refers you.
In cases where cancer has been confirmed, you should not have toÂ wait more than 31 days from theÂ decision to treat to the start of treatment.
Other cancer pages
The Health A-Z coversÂ many different types of cancer: