Smoking is falling, however most cancers is hovering… we ask the consultants why

Soaring cases of smoking-related cancer are being driven by medical advances, population growth and the legacy of widespread cigarette addiction, say experts.

New research shows the number of people diagnosed with cancer caused by smoking has hit an all-time high, with 160 new cases per day.

However, despite the 17 per cent surge in cases since 2003, the number of smokers has plummeted over the last 20 years.

Lung cancer researcher Dr Rob Hynds, of University College London, believes several factors are behind the surprising data — not least that even those who quit the habit two decades ago are still at raised risk of developing cancer. 

He said: ‘The proportion of people dying of lung cancer is declining as you would expect based on the reduction in smoking.

‘But our understanding of cancer is dramatically better now than it was, and that has enabled us to attribute more cancers and types of cancer to smoking.

‘For example, last year, a number of annual breast cancer cases were revealed to be caused by smoking and included in the statistics for the first time.’

He said population growth has limited the apparent reduction in smoking rates.

While the proportion of people smoking has fallen from 45 per cent in 1975 to 13 per cent today, the UK population has grown by more than 10 million in that time.

And medical advancements, including early detection and life-extending treatment, have contributed to the rise in cases.

‘We’re now significantly better at detecting cancer,’ said Dr Hynds. ‘Lung cancer screenings have started to be rolled out in England and increased public awareness of cancer means it’s being detected a lot earlier.

‘As well as finding more cases, these are being detected earlier, so patients have a better chance of survival.’

Dr Hynds said former smokers continue have an increased risk of being diagnosed with cancer for years after they quit.

‘We know that the lag time between the mutations that initiate lung cancer and the diagnosis can, in some cases, be as long as 20-plus years,’ he said.

‘Older people who started smoking at a young age are still coming through the system just as much as they were previously.

‘It is younger people who have never started smoking who have driven the decrease in smoking at the population level. As such, older people who started smoking at a young age and have smoked for a long time are still being diagnosed with cancers.

‘We already see a significant benefit in lung cancer mortality associated with tobacco smoking cessation. In the longer term, we might expect to see the current decrease in smoking reflected in decreased cancer cases.’

The research was carried out by Cancer Research UK, which is calling on the Government to re-introduce the Tobacco and Vapes Bill.

The new smoking law, first proposed by the Tory government, would have made it illegal for anyone born after January 1 2009 to buy tobacco products, creating a totally smoke-free generation.

Labour vowed to introduce similar legislation in its manifesto and is expected to announce this in the King’s speech on July 17.

Dr Katrina Brown, a Cancer Research UK statistician, said ex-smokers being diagnosed with cancer in later life are partly behind the increase in cases.

She told Mail Online: ‘Smoking prevalence has fallen and hopefully continues to fall, but smoking related cancer cases today are a legacy of smoking rates in decades past.

‘Even though we have seen smoking rates coming down, they haven’t come down steadily over time – there have been periods of flattening off and even slight increases.

‘That is what is causing the cancer cases that we see today, because it takes a while for smoking to cause cancer.’

She added population growth means that while the proportion of people who smoke has decreased, the actual number is still quite high.

‘Because people are living longer, there are more people in the population, so there are more people around to get cancer,’ she said.

‘The total number of people alive today who currently smoke or who have smoked in the past is arguably higher than ever because population numbers are higher.

‘When somebody quits smoking, it takes about 20 years for their increased cancer risk to return to the level of someone who had never smoked.

‘Quitting is still absolutely the best thing you can do for your health, but to an extent, the damage has been done.’

The researchers considered deaths from 16 different forms of cancer that have been linked to smoking.

Because the carcinogenic toxins from tobacco and nicotine travel around the body in the blood, they can cause a wide range of cancers.

Dr Brown pointed out that while smoking rates are down, people continue to take up the habit.

She said: ‘We know that socio-economic deprivation is associated with higher smoking prevalence.

‘Men are more likely to smoke than women, and young people who are exposed to smoking in their household are more likely to take it up.

‘The reasons why people do it are really complex, but it remains bad for everyone.’

Professor Sir Richard Peto, of Oxford University, said that while smoking-related cancer cases appear to be rising, the number of deaths has been falling over the last two decades.

‘Mortality matters more than incidence, and nationwide mortality trends can be estimated more reliably than incidence trends,’ he said.

‘Among both men and women, tobacco-attributed cancer death rates and tobacco-attributed overall death rates have been falling ever since the year 2000.’