Imagine for a moment you are a doctor, and you have just met someone at a social function. It's odds on that the conversation will quickly turn to cancer and when a cure for it will be found. That is really frustrating - because in the last 20 years or so we have cured many thousands of cancers, and a far higher proportion of people with cancer are surviving for longer than ever before.

Part of the success has been earlier diagnosis. People are more aware than they were of the early symptoms, and far more people, especially women, are coming forward for screening tests to detect early cancers while they are still apparently healthy. We are much better organised in breast and cervical cancer screening. And despite the well-publicised problems in some areas with cervical cancer smears, the screening has worked.

Screening for bowel cancer is beginning to bite, too, into the deaths from it. And although numbers of skin cancer cases are up, the fact that most people now know about the risks means that they come to the doctor with them far earlier than before. That often means the difference between a normal life and an early death.

One less well-known success has been in stomach cancer. Deaths from this disease have fallen steeply in the last few years. Part of this has been due to better eating habits, but some is definitely due to much better understanding of the cause of stomach ulcers. The germ now known to be responsible for ulcers, helicobacter pylori, is also implicated in causing cancers. In the last ten years we have concentrated on getting rid of helicobacter in our ulcer patients - and this is linked with the trend to fewer stomach cancers.

Treatments for most cancers have improved, too. The best news has been in children's cancers, deaths from which have fallen by more than 60 per cent between 1960 and 1995. There are several causes for this, all working together. One is that children's cancers are very sensitive to modern chemotherapy. Another is that children with cancer are now treated by doctors with different specialities working together on each child, using treatments that have been proved to work in properly planned and controlled trials.

Particularly pleasing has been the fall in deaths from breast cancer, and the fact that today's women with it live far longer and have a much better quality of life than ever before.

The researchers and doctors are doing their best to bring the figures down, but we need a partner in the fight - you. Because there is one huge cause of cancer that we need to tackle together: smoking. Smoking causes lung, throat, mouth, kidney and bladder cancer. It causes one-third of all deaths from cancer. It also causes one-fifth of all other deaths, mainly due to chronic bronchitis, heart attacks, strokes and gangrene in the limbs. Happily, nine million Britons have given up this biggest of all killers. Men have taken that message on board. If you are a woman smoker, please learn from them. Numbers of lung cancer cases are falling in men, but rising in women - entirely because more women are smoking than before. And lung cancer is one of the more difficult to cure.

If you notice anything that may indicate cancer, no matter how trivial, report it to your doctor. Signs and symptoms to report include:

Unexpected bleeding, whether it is in phlegm, or vomited, or passed in the urine or from the bowel, or outside the usual menstrual pattern

Any new mark or spot on the skin that doesn't go away, especially if it varies in colour, has an irregular edge, is enlarging, or bleeds

Unexplained loss of weight and appetite and/or excessive tiredness and weakness

Any persistent pain in the abdomen that doesn't respond to the usual indigestion remedies

Chronic pain anywhere in the body that doesn't respond to the usual painkillers

A Persistent cough, breathlessness, or a hoarse voice that lasts longer than a normal cold

Any new lump under the skin: it can be in the neck, breast, scrotum, armpit, groin, or anywhere else

persistent dizziness, nausea, double vision and headache not responding to rest and anti-sickness drugs.

Finally, don't be alarmed if you have one of these symptoms. Nine times out of ten it won't be caused by cancer.

Converted for the new archive on 30 June 2000. Some images and formatting may have been lost in the conversion.