FAQs about cancer

Q. What are cancer cells?

A. Cancer cells are cells that have lost control of their ability to divide in a controlled fashion creating a group of out-of-control, dividing and growing cancer cells – a tumour. Tumours induce blood vessel growth (angiogenesis). They may grow quickly or slowly.

Q. How does cancer spread?

A. Single cancer cells can break away from an established tumour, to spead locally or they may enter the bloodstream or lymph system, and be carried to a distant site, where they can take root and grow as a secondary tumour. They can also spread across body cavities.

Q. How many people in the UK get malignant cancer at some point in a lifetime.

A. 1 in 3. But it is heading towards 1 in 2.

Q. How many people get malignant cancer in the UK in one year?

A.  About 300,000 people – the equivalent of about 750 jumbo jets full of people.

Q. How many people die in the UK each year from cancer?

A.  In excess of 150,000 people. Slightly over a quarter or, put another way, about 1 in 4, of all deaths. This is the equivalent of about 350 jumbo jets full of people. The mortality rates have dropped by about 10% over recent years as treatment has improved; but because the incidence of cancer is increasing this may be difficult to sustain.

Q. Is cancer the commonest cause of death in the UK?

A.  Because death from the other main causes – heart disease, stroke and infectious diseases – has declined, Cancer became the most common cause of death (in females in England and Wales from 1969 and in males from 1995).

Q. Why are older people more prone to cancer in general?

A.  As people get older, they accumulate more changes in their DNA which means an increased likelihood of cancer. Older people may also have a less efficient immune system to stop cancer taking hold. In the UK about 70% of all newly diagnosed cancers occur in people aged 60 or over. Looked at another way, about 65% of cancers in the UK affect people over the age of 65.

Q. So, there are a complex number of co-factors that exist such as one’s lifestyle, age, the state of the immune system, environmental factors, genetic susceptibility that may determine whether one gets cancer?

A. Yes

Q. Is my country of origin going to impact on my genetic disposition to cancer?

A.  There is some evidence. One often quoted example is that the incidence of breast cancer in Japan is much lower than in the USA or the UK. However, the incidence of breast cancer in Japanese women living in the USA is the same as for the general population of American women. A deduction might be that the causes of breast cancer are more closely related to life style and the environment than they are to genetic make-up.

Q. How many different cancers are.

A.  It is often said: about 200. However, as we discover more about cancer this is a simplistic answer. Scientists are increasingly finding more and more variants within one cancer site meaning that different types within one type behave differently and require different treatment.

Q. Is there a gender difference?

A. Yes. A roughly equal number of men and women suffer from cancer but in the last 30 years the incidence of cancer in the UK increased by around 20 per cent in males and 40 per cent in females. Survival rates are slightly higher in women. The number of new cases, and deaths, from breast and lung cancer in women are higher in Britain than the European Union average.

Q. What are the commonest cancers?

A. The four most common cancers in the UK are breast cancer, lung cancer, bowel cancer and prostate cancer (taken together they represent about half of the new cases of malignant cancer).

Q. How is “survival” measured?

A.  Survival statistics for cancer are usually written as ‘5 year survival’ or ’10 year survival’ to show that a given percentage of patients were alive 5 or 10 years after diagnosis. But this can be very misleading as an individual’s situation is dependent on the circumstances e.g. the grade of the tumour and how aggressive it is. So, for some people using the published figures for a particular cancer will be optimistic and for others they will be pessimistic.

Q. Assuming the cancer is identified, what are the survival rates?

A.  Survival varies by type of cancer and a number of factors including sex, age and socio-economic status. The 5 year relative survival rate is very low for cancers of the pancreas, lung, oesophagus and stomach. On the other hand survival rates are better for:  colon cancer (nearly 50 % survival), cancers of the bladder, cervix and prostate (50-70 % survival) and breast cancer (80 % survival). For the majority of cancers, a higher proportion of women than men survive for at least five years after diagnosis. Among adults, the younger the age at diagnosis, the higher the survival for almost every cancer. The good news is that Survival rates for most cancers in both sexes are improving.

Q. How are some of these words like Cancer and Oncology derived?

A.  Attributed to Hippocrates, the earliest term for a benign swelling was Oncos (Greek); and malignant swelling was Carcinos (Greek), from which cancer (Latin) was later derived. It is perhaps no accident that carcinos also meant crab. Crabs move unpredictably and some tumours when examined might look something like a crab.