Inside the rise of lung cancer in non-smokers… and why a diagnosis is not the death sentence it once was if you spot the subtle symptoms early enough

It’s the disease that’s widely believed to result in particularly bleak outcomes. 

Lung cancer, which affects around 50,000 Britons every year, is the leading cause of cancer death in the UK, responsible for 33,000 fatalities every year.

Pope Leo XIV is the latest victim, diagnosed with the condition on Tuesday after the removal of a ‘suspicious’ nodule on his lung.

However, according to leading experts in the field, the disease is far from the swift death sentence it once was. 

Thanks to a recent revolution in treatments for the disease, the 71-year-old’s prognosis is likely to be extremely promising.

‘There’s a very good chance he’ll be cured,’ is the conclusion of Professor Hendrik-Tobias Arkenau, Consultant Medical Oncologist based at the Sarah Cannon Research Institute in London.

Not only have doctors removed the ‘early-stage’ cancer, as well as the entire lower lobe of his right lung, he is also likely to receive powerful targeted drugs that attack genetic mutations in the tumour that fuel its growth. Studies show this reduces the risk of recurrence by 70 to 80 per cent.

‘These drugs have dramatically changed the outlook for lung cancer patients,’ says Professor Arkenau. 

‘Years ago you’d maybe get a bit of chemotherapy and that was it. Prognosis was around nine to 12 months. These days, patients are living for years and years and years, with many of them cured.’

Patients benefit the most from the game-changing preventative drugs – if the disease is spotted early.

And experts say this is increasingly difficult given the rise in cases among non-smokers, like Pope Leo, who typically experience subtler signs of the disease.

Dr Alexandros Georgiou, Consultant Medical Oncologist at Guy’s and St Thomas’ Hospital in south-east London, discovered that the proportion of his lung cancer patients that have never smoked has increased over the last 30 years. 

‘This shifting demographic is partly due to the increasing prevalence of non-smokers in society, meaning the pool of non-smokers who could potentially get lung cancer is getting bigger,’ says Dr Georgiou. ‘But I don’t think that fully explains the change that we’re seeing.’

Now, experts are calling for public health campaigns to raise more awareness around early signs of the disease. 

‘We need people to know that lung cancer is not uncommon in people who don’t smoke,’ adds Dr Georgiou. ‘While new treatments are keeping patients with advanced disease alive for several years, spotting disease early gives the best chance of living a long, healthy life.’

Around 90 per cent of non-smokers diagnosed with lung cancer have a type of the disease called adenocarcinoma, which develops in the mucus glands in the lining of the airways.

Adenocarcinoma can also occur in smokers, but data suggests that these tumours are more likely to sit in the centre of the chest, causing more obvious and severe symptoms, according to Dr Georgiou.

This includes coughing up blood, a persistent and painful cough and extreme breathlessness. Non-smokers, however, often experience milder problems that can be easily dismissed as other, benign conditions. 

‘We think this might be because the tumours are in the periphery of the lungs where they cause less irritation to the airway,’ says Dr Georgiou.

‘But also, non-smokers have better lung function so can compensate for damage a bit better than smokers. 

‘Then you also have the fact that both patients and doctors are less likely to suspect the condition in someone who doesn’t smoke and is otherwise fit and healthy, and often younger, which leads to a delay in diagnosis.’

So, what should you watch out for?

Both experts say a persistent cough, which has lasted for more than two months, is the most common warning sign.

‘The problem is it’s often mistaken for the aftermath of a virus like the flu, so a GP might prescribe antibiotics and wait to see if they work before conducting further tests,’ says Dr Georgiou.

Professor Arkenau adds: ‘If you’re coughing every day, that’s a warning sign. It doesn’t have to be a painful or productive cough, or relentless. Just a regular cough that’s gone on for a couple of months.’

Fatigue is another red flag. 

‘The tumour can create inflammation in the lungs which can limit the amount of oxygen in the bloodstream, making you feel exhausted,’ says Professor Arkenau.

‘The cancer can also reduce red blood cell count, resulting in anaemia, which worsens fatigue.’

He adds: ‘Watch out for repeated chest infections. Tumours can block an airway meaning that air can’t properly ventilate the lungs, which makes you vulnerable to infections.’

In the majority of cases, non-smoking lung cancer is picked up once the disease has spread and is incurable.

‘The disease tends to spread to the bones and the brain where it causes symptoms rather quickly, such as back or leg pain and bad headaches,’ says Dr Georgiou.

But even for these patients, there is fresh hope.

A series of scientific breakthroughs have given way to in-depth knowledge about the genetic quirks of lung tumours that fuel their growth. 

Targeted therapies – including drugs called tyrosine kinase inhibitors – have been developed to attack these defects in the cancer’s DNA, with strikingly positive results. 

A major 2024 trial revealed that, when given after surgery, these medicines can reduce the risk of recurrence by 70 to 80 per cent.

What’s more, when given to patients with advanced disease, the treatment can quadruple lifespan – from around a year to five, studies show.

‘When I started in oncology there was just two types of lung cancer,’ says Professor Arkenau. ‘Today, there’s more than 20 types that we know of, and can treat with a variety of targeted drugs.’

New immunotherapy drugs, which help the patient’s immune system to fight the disease, are also showing promise. 

These treatments are proving particularly effective in non-smokers, whose tumours are more likely to be driven by specific genetic mutations.

One patient to benefit is Mel Erwin – a mother-of-three living with incurable lung cancer. She has never smoked.

When disabling fatigue struck in 2020, aged 51, she assumed it was due to the constant juggle of work and parenting, and a recent bout of Covid-19.

But when, within a few months she struggled to walk to the end of the road without feeling out of breath, she made an appointment with the GP.

Her doctor refused to see her in person due to pandemic restrictions.

Over the phone, the GP listened to the former literary executive describe her symptoms and responded: ‘What would you like me to do about it?’

Unsatisfied, she sought a second opinion with another doctor, who referred her for a series of tests.

‘My bloods were fine but they’d found a mass in my left lung,’ Mel recalls. ‘I asked if it was Covid or cancer – and he said it could be cancer.’ 

The day after her 52nd birthday, Mel had half of her left lung removed, followed by radiotherapy and chemotherapy. 

But two years later, a scan showed new lesions across both her lungs that were too small to biopsy.

After another two years of monitoring, Mel was then diagnosed with advanced, incurable lung cancer.

Due to a specific genetic mutation within her tumour, known as EGFR+, she was eligible for a targeted drug called osimertinib.

‘They told me the drug sometimes works for 18 months… or up to eight years,’ she says.

This spring marked six years since her diagnosis and, according to her most recent scans, Mel has no active disease.

‘This drug is allowing me to live well, and I plan on living for decades,’ says Mel, who took part in Sir Chris Hoy’s fundraising charity bike ride Tour de 4.

She hopes more people will be aware that it’s possible to get lung cancer without a history of smoking – and to push if they have any symptoms of the disease.

‘For people with no history of smoking, be aware of potential symptoms,’ she says. ‘A cough, chest infections, breathlessness but also weight loss, fatigue and pain in the neck, shoulder or back.’

As for the mysterious reason behind her illness, Mel is intrigued by growing evidence about the impact of pollution.

‘Research shows that possible domestic pollution, wood burning and coal fires could have contributed, but who knows.’

Ultimately, her advice is to ‘persist with doctors until you get answers’.

She adds: ‘Don’t worry about making a nuisance of yourself – be a nuisance if something is wrong.’