Frequently asked questions

What is cancer?

What is cancer? According to the World Health Organisation, cancer is a generic term for a large group of diseases that can affect any part of the body. Other terms used are malignant tumours and neoplasms. 

A key defining feature of cancer is the rapid creation of abnormal cells that grow beyond their usual boundaries, and which can then invade adjoining parts of the body and spread to other organs; the latter process is referred to as metastasis. Widespread metastases are the primary cause of death from cancer.

What causes cancer?

The World Health Organisation says cancer arises from the transformation of normal cells into tumour cells in a multi-stage process that generally progresses from an initial pre-cancerous lesion to a malignant tumour. These changes are the result of the interaction between a person's genetic factors and external factors, known as carcinogens, which take three forms:

• Physical carcinogens, such as ultraviolet and ionising radiation
• Chemical carcinogens, such as asbestos, components of tobacco smoke, alcohol, aflatoxin (a food contaminant), and arsenic (a drinking water contaminant)
• Biological carcinogens, such as infections from certain viruses, bacteria, or parasites.

How many different types of cancer are there?

There are more than 200 types of cancer.

What are the most common types of cancer in Wales?

• Lung cancer
• Bowel cancer
• Prostate cancer
• Breast cancer

What does Cancer Research Wales do?

Since 1966, Cancer Research Wales has invested over £35 million to fund the best researchers, clinicians and health professionals to push the boundaries of cancer research here in Wales.

Our research delivers hope for people affected by cancer today and will transform the future for the patients of tomorrow and tackle cancer inequalities in Wales.

We fund research across four broad themes:

• Discovery and translational research
• Early diagnosis, prevention and screening
• Better treatments
• Health systems and outcomes

We currently have over £7,600,000 invested in 40 live projects that are researching quicker diagnosis and better and kinder treatments for cancer.

This includes almost £3,000,000 that we have invested in four clinical trials based here in Wales.

You can find more about our pioneering cancer research here.

I'm worried about cancer - where can I go for help and advice?

If you are worried about cancer or need more information about spotting the signs of cancer, reducing your risk of cancer, cancer treatment, symptoms and sources of help, please visit NHS Wales.