This is an exciting
study that does show an impact on mortality, which has not been a screening
result from previous studies. What it doesn’t tell us exactly is: What does
this mean from a policy standpoint?
We need to look at a lot
more to see what’s the best model with this kind of screening and when this is
screening appropriate. I think the authors of this study were right to say that
this is a very positive result and it’s helpful … but that the best way to
implement this in day-to-day practice still is not completely resolved. There’s
a lot more work to be done in that regard.
One message that is still
very clear is that if you don’t want to die from lung cancer, you need to stop
smoking or never start smoking. This still has to be foremost in our public
health preventative message.
The study results do help
by saying that screening can have a role in day-to-day practice. The fact that
these patients were treated in a community setting showed that … the process
for diagnosing lung cancer can be handled by community physicians. I’m a
pulmonary physician. So when I sit down with patients who have the risk of
smoking, and we talk about what is the role of getting a low-dose CT scan for
screening, I think I have a lot more information to help both me and the
patient to decide whether this is beneficial to them versus a risk.
In the past, with CT
screening there was certainly risk from the radiation and risks for having
unnecessary procedures done, but no real proven benefit that we were going to
impact mortality if we found an early cancer. The study results do add value on
a day-to-day basis.
We just don’t know whether
it’s something that should be applied to everybody. Another question is whether
there are there markers that might help in this group of individuals to
identify who is at high risk for fast-growing tumors or for slow-growing tumors
Are there biologic markers that we can find with a blood test that might add to
this information to help us sort out who would benefit from screening or not?
[Other questions to
answer] from these data or from other ongoing studies include: Are there
subgroups of this 55- to 74-year-old population that are at higher risk? Are
there individuals who with less frequent screening can do just as well? Are
there individuals for whom more screening is necessary? The population looked
at [in the study] was a narrow window of high-risk individuals … It represents
about 7 million people out of the 94 million current and former smokers that we
have in this country.
We may even be able to
look at genetic markers at some point in the near future to determine who is at
higher risk and that will help us better identify who needs to be screened. I
think biomarkers and genetic markers all could be added to the formula when
we’re trying to decide what the best risk population to be screened is.
Screening tools work best when the screening population is well defined.
So now we have evidence
that screening in general can have an impact on disease. Unfortunately, prior
to this, lung cancer was diagnosed too late to make a big impact for most
patients. In lung cancer, an earlier diagnosis hopefully impacts mortality.
Lung cancer could become a curable disease if it’s found early enough to be
completely resected.
Dr. Albert A. Rizzo is
chair-elect of the American Lung Association board and chief of Christiana
Care’s pulmonary and critical care medicine section in Newark, Del.
He has no conflicts of interest.