Urgent call for action on lung cancer in people who have never smoked

Lung cancer in patients who have never smoked is on the rise but is often diagnosed later, leading to poorer outcomes for patients, scientists have warned.

Smoking is the leading cause of premature and preventable death globally and is responsible for more than a quarter of all cancer deaths in the UK, according to Cancer Research UK.

But in 2020, lung cancer in people who had never smoked was the fifth most common cause of cancer death worldwide, second only to tobacco-related lung cancer. Those who have never smoked make up about 14 per cent of all lung cancer cases.

Despite this, the overwhelming majority of lung cancer screening resources are directed towards smokers. In the UK, there is no routine lung cancer screening for people who have never smoked.

A review by researchers at University College London (UCL) called for action to increase funding for screening and researching into the causes of lung cancer in never-smokers.

"Most lung cancer cases are caused by smoking, but this paper helps to highlight this isn't always the case. Cell changes that can lead to cancer can happen at random in lung cells just as they can throughout the body,” Dr Rachel Orritt, health information manager at Cancer Research UK told the Independent.

She explained factors such as air pollution, exposure to certain chemicals and being related to someone with lung cancer are all risk factors.

“Other factors such as air pollution and exposure to some chemicals linked to certain industries, such as silica, can increase the risk of the disease. Having a parent or sibling that has had lung cancer, or living in an area that has high levels of a naturally occurring gas called radon, can also have an impact,” Dr Orritt added.

The research published in the journal Trends in Cancer reviewed evidence from studies of several thousand lung cancer patients in the US and UK.

The findings suggest the number of lung cancers being diagnosed in never-smokers has also risen. Cases in the UK study doubled between 2008 and 2014.

But because most lung cancer screening is directed at smokers, lung cancer in never-smokers is often diagnosed later, leading to poorer outcomes for patients.

Study author Dr Deborah Caswell said a new strategy is needed to detect this type of cancer earlier because many people do not “fit the expected profile”.

“If a young female non-smoker goes to her GP with shoulder pain, it may not even occur to the healthcare professional that lung cancer could be the cause,” she said.

“Lung cancer in never-smokers is not currently thought of as a different kind of lung cancer, which is making it more difficult to intercept at an early stage. Fewer people today are smoking, which is a good thing, but that has led to the proportion of lung cancer in never-smokers increasing, meaning we need better screening programmes and a better understanding of the causes,” she added.

While pollution, secondhand smoke and genetics are all risk factors for lung cancer, the relative risk associated with each of these factors in comparison to smoking is modest, making screening for these risks harder to justify.

For example, about 33,500 cases are caused by smoking in comparison to 3,600 caused by outdoor air pollution.

"We can't control everything that affects our risk of cancer, but if someone spots something that's not right for them, they should talk to their GP. It probably won't be cancer, but if it is, spotting it at an early stage can make all the difference,” Dr Orritt said.