“Current and former heavy smokers can now be screened more effectively for lung cancer. Results from the National Lung Screening Trial (NLST) revealed that detecting small lung cancers with computed tomography (CT) reduces lung cancer specific mortality by 20 percent.”
Wow, how amazing is that? Thanks to the MDACC Provost, Dr Ray DuBois for sharing it on Twitter and to Dr Jack West (Swedish) for Re-Tweeting it or I may well have missed it. The action is as a direct result of The National Lung Screening Trial (NLST), which was conducted to evaluate whether screening with low-dose CT scans could reduce mortality from lung cancer.
Yesterday, The National Lung Screening Trial Research Team published the results of a landmark study (see references below) that may well have a huge impact on cancer centres around the USA. Here are the basic details of the study:
“Eligible participants were between 55 and 74 years of age at the time of randomization, had a history of cigarette smoking of at least 30 pack-years, and, if former smokers, had quit within the previous 15 years.
Persons who had previously received a diagnosis of lung cancer, had undergone chest CT within 18 months before enrollment, had hemoptysis, or had an unexplained weight loss of more than 6.8 kg (15 lb) in the preceding year were excluded.
A total of 53,454 persons were enrolled; 26,722 were randomly assigned to screening with low-dose CT and 26,732 to screening with chest radiography.”
Emphasis mine. That’s a huge epidemiology study that took place over two years of enrollment and 5 years of screening!
What did the results show?
Essentially, my understanding is that screening with the low-dose CT did indeed reduce mortality from lung cancer compared with radiography:
“In the NLST, a 20.0% decrease in mortality from lung cancer was observed in the low-dose CT group as compared with the radiography group.
The rate of positive results was higher with low-dose CT screening than with radiographic screening by a factor of more than 3, and low-dose CT screening was associated with a high rate of false positive results.”
Until only very recently, people with lung cancer were given radiography, tested for histology and categorised according to small cell or non-small cell, and then the latter in to squamous or non-squamous and then treatment (mostly with chemotherapy) decided from there on.
As MDACC noted:
“Prior to the trial, lung cancer, often diagnosed in the later stages of the disease, had shown no benefit from screening because screening with standard chest X-rays did not detect cancers early enough.”
We’ve come a very long way in five years.
These results now mean that with the advanced in low dose CT, we can now potentially detect lung cancer earlier, thereby improving their chances of better outcomes. On the Global Resource for Advancing Cancer Education, GRACE, Dr Thomas Hensing (U. of Chicago) summarised it succinctly:
“As the first trial that shows lung cancer screening can save lives, the NLST will no doubt have a significant impact on how we practice in this country and should be viewed as a very hopeful result for lung cancer advocates.”
Curious as to what the impact might be at major cancer centres, I asked Dr West on Twitter whether Swedish would be doing screening following the response. His response, I’m delighted to say, was enthusiastic:
“Yes, Swedish is very inclined to roll out screening program for current/ex-smokers.”
The results of this study, coupled with rapid implementation in many cancer centres, may have a huge impact on earlier detection, diagnosis and outcomes five years from now. That’s great news for patients and caregivers and gives hope to all. In fact, it gives me goosebumps thinking about it!
Imagine if we can detect lung cancer earlier, that not only means a better chance of outcomes per se by dint of treating earlier disease, but add in what we now know about molecular aberrations in adenocarcinomas and squamous cell carcinomas as well, and things really start to snowball. The overall impact may well be greater than we can imagine at present.
If you are interested in more information, MDACC put together a short video explaining the background and impact of the NLST study that is well worth checking out.
Disclosure: I’m an unpaid member of the GRACE advisory board.
The National Lung Screening Trial Research Team (2011). Reduced Lung-Cancer Mortality with Low-Dose Computed Tomographic Screening New England Journal of Medicine DOI: 10.1056/NEJMoa1102873