‘Covid’ cough could be lung cancer

A chronic persistent cough should not be automatically dismissed as a lingering symptom from the virus.

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A chronic persistent cough should not be automatically dismissed as a lingering symptom of covid, says an Australian respiratory expert. 

The advice follows a new perspective piece published in the Medical Journal of Australia that shows the incidence of lung cancer in people who have never smoked – particularly women – is on the rise. 

While rates of lung cancer were still highest among people who have smoked, the incidence is growing among Australians who have never smoked.  

“We’re definitely seeing more and more cases,” said lead author Professor Fraser Brims, deputy director of the Institute for Respiratory Health, and a consultant respiratory physician at Sir Charles Gairdner Hospital in Perth.  

“Occupational exposure is a very big driver for Australia,” he said. “We’ve got a chequered history, particularly with regard to asbestos in the past, and that’s an ongoing concern for sure.”  

The rising rates of lung cancer in non-smokers was important for GPs to be aware of, especially as the number of people who’ve recovered from covid grows, Professor Brims told The Medical Republic. 

A lingering cough was a common symptom, making it important that both patients and GPs didn’t overlook other causes, he said. 

“For the vast majority of people, their symptoms should be resolved within a handful of weeks,” he said. 

“So, if it is dragging out beyond and there’s concern with other symptoms or background risks, then I think it’s very reasonable these days to request a low dose CT scan to just to reassure everybody as to what’s going on.” 

Other lung diseases, such as emphysema, bronchitis, ongoing infections and fibrosis also raised the risk of lung cancer.  

According to the MJA article, researchers increasingly recognised that lung cancer in never smokers was biologically distinct from smoking-related lung cancers. Although there was overlap with other risk factors such as environmental and genetic interactions, biofuel and occupational exposures, and indoor and outdoor pollution. 

“The incidence of lung cancer in several developed countries (e.g., the United Kingdom and the United States) has started to fall,” the authors wrote. 

“However, despite a projected fall in age-standardised lung cancer rates in Australia over the next two decades, the number of deaths from lung cancer is expected to continue to increase due to population growth and ageing.” 

Professor Brims told TMR the key to improving the five-year survival rate of 19% for all lung cancer in Australia was earlier detection. 

And that means thoroughly investigating chronic, persistent and changing coughs in all patients, regardless of their smoking history or even whether they have had a recent covid infection. 

“It’s the more than three weeks of a new cough or a changed cough would absolutely be something we should take seriously,” he said. 

“The same really stands for the breathlessness or chest pain and just that nonspecific fatigue. A clear red flag will be haemoptysis. Not all haemoptysis is lung cancer, but it’s absolutely one of those things we should think of early.” 

He said smoking history should be routinely checked and age was also a consideration. 

“So, if someone is 70, having smoked with some of those worsening symptoms, then absolutely, we should be thinking (of checking for lung cancer); but if they’re 45 and have never smoked, then it doesn’t mean they definitely haven’t got lung cancer. 

“Their background risk is far less and then it does get tricky to know what to do for sure, but we must think about it in these people in everybody, particularly as they get older because age, of course, is one of the biggest drivers.” 

Professor Brims said lung cancer screening with low dose computed tomography in current and former smokers had been shown to significantly reduce lung cancer mortality by 20% to 24% in two large, randomised studies. 

“The federal government has given Cancer Australia money to work on an implementation project, it’s just that we’re all kind of being impatient,” he said. 

“We know we know screening is effective, [because it] identifies lung cancer at an early stage when it can be treated and that confers a more clear mortality benefit. 

“We know that screening is only effective when you’re identifying a high-risk population, and so there’s work around how do we do that in the Australian context, and I think it’s doable.” 

Professor Brims said it was time to move past the general view that lung cancer was a smoker’s disease.  

“We have to move on from the stigma and bias, be it conscious or unconscious, against lung cancer,” he said in an MJA podcast. 

“As a community, both the lung cancer community and the medical community as a whole, we have to move past this. 

“It’s not fair to judge individuals by a risk factor. We don’t judge people who’ve had bowel cancer and say, ‘goodness, you must have eaten a lot of processed red meat in the past.’ And we shouldn’t be doing the same with lung cancer and smoking because it’s not about that anymore.” 

Medical Journal of Australia 2022, online 18 April