Update on new research for surgery in elderly cancer patients
Prof Mike Jaklitsch - Harvard Medical School, Boston, USA
You’ve been giving an update on new research for surgery particularly in elderly patients with cancer. Can you tell me, what are the accomplishments so far, do you think, that surgery has achieved, now especially in lung cancer where you’re working?
In lung cancer our greatest accomplishment has been finally open low dose CT scan for screening for lung cancer. Patients who are between 55 and 77 years of age who have a 30 pack/year smoking history and have smoked within the last 15 years can now have a meeting with their primary care physician to talk about the risks and benefits of screening and then undergo low dose CT scan screening. So this is a major change and is probably the greatest accomplishment of the previous year.
Give me the data on that because it’s controversial, isn’t it?
It is controversial. The National Lung Screening trial was a phase III study that looked at people between the ages of 55 and 74 with a 30 pack/year smoking history and it reduced lung cancer specific mortality by 20% after just three annual screens. That was completed in August of 2011 and it’s taken about four years to take a positive phase III study and turn it into public policy.
So that’s lung cancer specific mortality, what about overall mortality?
Overall mortality was less within the screened population but the important parameter of lung cancer specific mortality was always felt to be the ultimate measure of the effectiveness of screening. There were previous trials that looked at chest X-rays where there was a reduction in mortality but it was not lung cancer specific mortality, so it was felt difficult to interpret that data. The lung cancer specific mortality was always the holy grail of the final outcome measure to show that screening was really making a difference and there’s every reason to believe that if you put in an annual screening programme for more than three years that lung cancer specific mortality will drop even more.
How much lead time has the CT given you, in fact?
It’s estimated it gives about 2½ years. So, instead of seeing tumours come in with 56% being stage 4 and another 26% being stage 3, there is a sincere hope that 50% or more will come in at stage 1. Smaller tumours means that lesser operations can be done, potentially radiation therapy can be done for cure and the cure rate should further improve.
Successful resection, curative resection, has always classically been in those very early stage patients. How far can that go, could you use CT earlier?
If you look at the National Lung Screening trial, they had an 88% cure rate so 88% in actually the I-ELCAP study which was a precursor study was at ten years. So that’s really quite dramatic. If you look at our stage 1s right now it’s about a 70% cure rate but the reason why is because even though they’re still stage 1 they’re coming in as larger tumours.
What’s the downside, though, of having this sort of screening programme?
Actually there is some anxiety whenever you lay down in a CT scanner are they really going to find a nodule or not. There are theoretical concerns that if you find out that your screen is negative this will be a green light to you to continue smoking whereas we believe smoking cessation is a very important part of the entire programme. Then there’s a possibility that you’ll find a nodule that’s not truly cancer. The safeguards that we’ve tried to build into that system is the positive scans for the most part are going on with additional scans, so they’re not being passed on to surgery where you’re taking out benign nodules, you’re using a repeat scan four months, six months or a year later to verify that the nodule seems to be growing and thus is at high risk of being a cancer. Secondly, the smoking cessation programme is an important integral part. So, as opposed to a risk, we think it’s a plus. People who are willing to come in to see if they have a tumour and participate in screening then come with the specific opportunity to discuss what is their smoking habit and what can medicine do to support them with smoking cessation?
So it seems the big payoff really is smoking cessation because you could have it confounded by lead time bias; just as there’s a controversy in DCIS detection for breast cancer, you might have lesions which are never going to develop into true lung cancer.
We think that’s less common with lung cancer. There are such things as ground glass abnormalities but they’re clearly a minority. The vast majority of the spots in lung actually will go on to become an invasive cancer and there is a difference between a lead time bias and true lead time. So the opportunity with screening is it gives you a true lead time of 2½ years and thus be able to cure a highly lethal cancer.
Of course, this whole idea of catching a cancer early is fixed in the public mind that that’s a good thing. It’s not always the case though but you’re saying in the case of lung cancer it really does help.
It really does help and if you wait for the symptoms to develop, the symptoms of lung cancer truly are awful. I think lung cancer is pervasive enough that we’ve seen untreated lung cancer with the coughing up blood, having water form around your lungs so you can’t breathe, the emaciation that comes from a patient suffering from untreated lung cancer. The world would be a better place if we could eliminate that.
And in the context specifically of older patients, how do you place this whole idea of CT screening and getting that lead time to potentially cure lung cancer?
I’m proud to say that SIOG had a role to play to elevate the highest age that was appropriate for screening from the planned age 74 up to age 77. It is conceivable that as our elderly population becomes more vigorous that that age could even be pushed out further. Everybody knows of somebody who may be 75 who may not be appropriate for screening because they’re debilitated and wheelchair bound and everybody knows an 85 year old who it’s hard to believe would not be eligible for screening because they’re so vigorous and perhaps still engaging in 5k road races. What we really need is a way to individualise it to the functional status of each patient and we hope that that will come in the future.
Of course I need to ask you about what doctors should be doing about this, though of course it’s what governments should be doing about it. But nevertheless doctors, what can they do, do you think?
I think the caveat that there be a shared medical decision making meeting between the patient and their primary care physician to talk about what are the risks and the benefits is an educational opportunity so that the patient is not just going for screening with no background to understand the results of that screening but gives them an opportunity to decide whether or not screening makes sense for themselves. Even if they decide not to go on to the low dose CT scan screening, that meeting is an opportunity to also discuss smoking cessation.