The devastating diagnosis of lung cancer in patients with COPD has led to some interesting observations such as the apparent higher sensitivity to immune checkpoint inhibitors (ICIs) in patients with both diseases compared to lung cancer alone.
Speaking at TSANZSRS 2019 on the Gold Coast, Professor Ian Yang highlighted recent research that found in lung cancer patients treated with pembrolizumab, those with co-existing COPD had improved overall survival and progression free survival.
Professor Yang said while the evidence was currently from retrospective studies, it suggested the tumour microenvironment was worth pursuing for clues to new clinical advances.
“It needs to be proven yet in prospective RCTs if these agents might be better in some sub-groups such as COPD versus non-COPD.”
Professor Yang, from Brisbane’s Prince Charles Hospital, said from a chemoprevention point of view there was some evidence that inhaled corticosteroids in COPD might reduce the risk of lung cancer.
Again, the quality of the evidence was not yet convincing but inhaled corticosteroids have been shown to inhibit airway epithelial mesenchymal transition (EMT), a suggested link between COPD and lung cancer.
He told the limbic that avoiding smoking, air pollution and carcinogens would prevent both conditions.
“That’s the big public health message. But even so, there are people with COPD who have quit smoking that still have an increased risk of lung cancer. The epidemiological studies show that one of the risk factors for lung cancer is COPD. It’s a 3 to 5 fold increased risk and that’s even adjusting for smoking history.”
Professor Yang said there were likely to be a number of mechanisms including inflammation and oxidative stress involved in the development lung cancer in the context of COPD.
“I think it is about understanding the local tumour microenvironment, that is the immune system; immune surveillance, maybe the microbiome and repair. What is the environment that promotes the tumour to start with?”
He said there was ongoing research on how to distinguish COPD patients with lung cancer at an early enough stage to facilitate the best possible outcomes.
Breathomics – using field asymmetric ion mobilising spectrometry (FAIMS) to detect volatile organic compounds (VOCs) in exhaled breath – was one potential, novel technique for early detection.
While VOC profiles were showing promise in distinguishing people by smoking history and healthy people from patients, it was not yet distinguishing between lung cancer and COPD patients.
He said liquid biopsies – analysing the tumour microRNA circulating in the blood – was another possible tool for predicting lung cancer in COPD.