Quit Insights Clinical Series Podcast with Associate Professor Henry Marshall about smoking cessation in lung cancer screening.
This podcast and article content is intended for health professionals and is for educational and informational purposes only. The content discussed does not constitute medical, legal or professional advice and should not replace your own clinical judgment.
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Our podcast guest was Associate Professor Henry Marshall, who is a thoracic physician at the Prince Charles Hospital and University of Queensland Thoracic Research Centre. He's an investigator on the NHMRC Centre of Research Excellence to prevent and detect curable lung cancer. Doctor Marshall's clinical and research interests are in the early detection and prevention of lung cancer through screening and smoking cessation.
What is the current evidence on how smoking impacts lung cancer risk?
Smoking is really important for lung cancer risk. It's the leading cause by a long way for lung cancer risk. In Australia, about 90% of men with lung cancer will have a smoking history. In about 65% of women with lung cancer will have a smoking history. All up, it's about 80% overall of lung cancer is attributed to smoking. It really ramps up that risk. There are other risk factors of course - air pollution and occupational exposures. But if you smoke cigarettes, you're about 15 to 30 times more likely to get lung cancer than people who don't smoke. That's even down to just a few cigarettes a day, and that accrues over time. The longer you smoke, the more years you smoke, then the more that risk goes up.
Do you think it's ever too late to quit smoking in terms of reducing lung cancer risk?
It is never too late. Even if you know you're unfortunate enough to be diagnosed with lung cancer, that's still never too late to quit as well. There's good data out there to show that if you can quit smoking at or around the time of lung cancer diagnosis, you still get a survival advantage of about 30% compared to if you continue to smoke. It's definitely never too late. Clearly, the earlier that you can quit smoking, the better, because that will reduce your risk over time as well.
Is it a requirement to quit smoking to access the National Lung Cancer Screening Program?
It's not a requirement at all.
Can lung cancer screening be an opportunity to discuss smoking cessation, in a non-stigmatising way?
Yes it’s an excellent opportunity, and we should not pass up this opportunity. I’ll recap the eligibility criteria of the National Lung Cancer Screening Program and maybe just say a few words about that, because this is a new program. It's a really exciting program. It's the first screening program in almost 20 years, and it started in July last year, and already 70,000 Australians - that's about 250 people a day, have signed up to the National Lung Cancer Screening Program. There's a huge public appetite for this. People are really interested. They know they've been at risk and they want to check out their lung health. The eligibility criteria for people aged 50 to 70 and the smoking criteria alongside that is only for people with a smoking history: 30 pack-years of exposure, either current smoking or quit within the last ten years. Smoking history is part and parcel of assessing eligibility. If you're going to be asking the question anyway, then it's a great springboard into talking about smoking cessation at that point in time. Don't miss out on that opportunity, I would say.
We know from a lot of literature, including in the lung cancer screening space, that the majority of people who've smoked long term regret that decision. If they had their time again, they would not do it. The general public are really well aware of the connection between smoking and lung cancer. The sort of individual that takes that step, they know that they've been a smoker for a long time, they know they're at risk of lung cancer. It's quite a daunting and intimidating thing to step forward and say, “actually I want to know, let's have a look”. That's quite a big deal. Stigma is really important, it’s a real barrier to some people. The way that we talk to people about lung cancer screening and about smoking cessation absolutely has to be person-centric, non-judgmental, and non-stigmatising.
What evidence is available from other regions regarding smoking cessation outcomes among individuals involved in lung cancer screening? Is it a golden opportunity? How do we best use it?
There's a really good consensus across lung cancer screening studies from Australia, Europe and North America that people who enrol in lung cancer screening have higher rates of quitting than the general population, which reflects this sort of motivation. They're taking a very proactive step to better health, and they're definitely more motivated to quit. Those quitting rates are generally around about 15% per year, which is significantly higher than the general population which is around about 5%. However, there's still 85% of people that continue to smoke, so we've still got a lot of work to do.
Data shows that the benefit of combining prevention and smoking cessation with early detection screening is really synergistic. The mortality benefit for lung cancer death is about 21% just from screening on its own. Quitting smoking for seven years has about the same benefit, around about 20%. If you combine those together then you can actually achieve a lung cancer mortality benefit of 38%, which is huge. Plus, you get an all-cause mortality benefit as well, because we know that smoking causes over 40 different other diseases and conditions. The important one for lung cancer screening is coronary artery disease, we can actually pick that up, coronary artery calcification on the CT scan. It really does work together very, very well. That's part of the opportunity to really almost double the benefit from just getting a scan on its own, to bundle that up with long term smoking abstinence brings good individual benefits.
What do you think is best practice smoking cessation care?
There's been a lot of research in this area recently, particularly from North America with the SCALE Collaboration. What we're seeing is that what works well in the general population works well in the screening population, i.e. more intensive interventions lead to higher cessation rates. That's what we would really advocate for.
The model that we use in Australia, which I hope listeners are aware of, it's a model promulgated right by Quit. It's the Ask, Advise, Help model - three simple and important steps, which I'll just run through. Ask - you're going to be asking this anyway. When someone comes in and talks about lung cancer screening – ask do you smoke?, have you smoked? This is the recommendation from the national RACGP guidelines. Ask about smoking and vaping at every opportunity, at every clinical encounter and keep that medical record up to date. The reason is that we know that nicotine dependence is a chronic relapsing and remitting condition, and just because someone's quit now, that may change. Stress or something may happen in their life which unfortunately causes them to relapse. We have to check in on people every time.
The advising part is really just working out a plan, a patient-centric plan, talking about how you can help them. The treatment is that combination of behavioural support plus medication and then working out what's going to work best for that person in their particular situation and getting a plan that they can be happy with.
The help part, that's the third step. This is the critical part that we often fall down on. We're quite good at asking and we're quite good at advising. Then actually providing the practical help is really key. That's basically putting that plan into action, either providing the behavioural support yourself if you've got training for that and many general practitioners may have that, or referring on to a local counsellor, psychologist or of course, telephone Quitline, and then prescribing whatever medication you've agreed on with the patient and making sure that they know how to use it.
The second part of the help, which I think gets lost a little, is that you need to check in with your patient a few weeks down the line and just see how they're traveling. How are they going? Do we need to troubleshoot any issues with the medication? Are they going well? Do we need to change our plan a little, and modify things? That's really important. As a hospital physician, I certainly can't see patients back in two weeks. I would definitely delegate that to Quitline. And I refer everyone really to Quitline, that’s my go-to for the behavioural side of things. We're looking at multi-session behavioural support with maybe varenicline as a tablet, or combination nicotine replacement therapy is equally effective. Those would be my starting points really for treatment.
One other thing probably that I might just mention is that most people who undergo lung cancer screening get a clear CT scan, they don't have a nodule. We're seeing about 80% of people are just going to go on and have their next CT scan, which is in two years' time. They don't have any kind of nodule of concern. It's really important that the practitioner and the patient understand that doesn't mean that you're immune to cigarettes, doesn't mean that you're somehow not going to get cancer. That just means at this point in time, you don't have cancer. This is not a green light to continue smoking, it’s a really good opportunity to quit now whilst you're ahead. You don't have cancer: it’s a brilliant time to try to get rid of the smokes. People are eligible for screening from the age of 50 through to 70, so they're in it for a long time, it's a 20 year program. It’s important that people understand throughout that journey that they might not be ready to quit immediately, but that's a conversation that you just keep having. And eventually they may decide the time is right.
Do you have any other tips for clinicians when talking to their patients about quitting smoking, in a non-stigmatising way, in the context of lung cancer screening?
Yes, it's funny how we approach smoking: it's a chronic disease. And I don't know why we deal with it in a different way to other chronic diseases. Think of COPD, diabetes, or hypertension, we say “well, you've got high blood pressure, we're going to treat it because otherwise you're at risk of stroke, heart attacks etc, and this is the medication that we're going to use”. It's an opt-out model of care. Of course the patient may not want to take any tablets or they take the prescription and throw it in the bin on the way out. You've given them the best advice. Whereas with smoking, it's much more of an opt-in model that we use. The patient really has to ask us to get help. I think the first thing is we should be moving to an opt-out model. That is, we identify people who currently smoke and we give them the best practice advice and take it from there. We're not waiting for people to come to us asking for help, we're being really proactive.
The second thing I would say, is to approach this as you would any other topic. The patient has to be central to the conversation. They're a partner in this, they're the ones that have to do all the hard work. It's really got to be a team effort and collaborative rather than a paternalistic way of dealing with things. Please be up to date with your medical education. It’s the same for anything else. You are the expert. Make sure that you've got up to date information. Use Quitline, and Quit Centre for health professionals. There’s a lot of free education materials. A lot of other professional societies also provide this. There's no shortage of really great CME to update yourself. So those I think would be my tips.
Can you share an example of where screening has led to someone quitting?
Absolutely. We're running some studies at the moment, some randomised controlled trials that are looking at people undergoing screening and helping them with smoking cessation. We've had some really lovely feedback. We collect the sort of feedback as part of the trial outcomes. We've had people saying, “you know, I've been smoking for 20 years or 30 years, and this has really helped me focus in on my smoking and the help that I've got from Quitline and from the medication, and just being more aware of my lungs, has allowed me to quit smoking and I've been quit for six months”. We've had lots of feedback like that, it’s a wonderful thing. I see patients in clinic with COPD and lung nodules and all the rest of it. And I do have, like GPs, quite a long-term relationship with a lot of my patients and will see them over many years. We'll always talk about smoking cessation. The time when someone does actually quit, it's brilliant and it's wonderful, and it's definitely a cause for celebration in the clinic, that's for sure. Because they've been struggling with this for a long time and they've made it happen and they feel great about it. It's just fantastic.
Our thanks to Associate Professor Henry Marshall for sharing these important insights with us.
Further information
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