Lung Cancer Screening in High Risk Patients

For the question of whether lung cancer screening in high risk patients causes more good than harm, check out this article.

I’m pretty convinced the data shows that in a research study high risk population where the scans are read by highly skilled experts closely following the rules, lives are saved by CT screening and the cost is reasonable for each QUALY.

Further, the interpretation of these chest CT screening exams is fairly straightforward for experienced and trained radiologists. That suggests that when CT screening is extended beyond research to broader community practice, results should also be good.

Analyzing the Cost-effectiveness of Low-dose CT

We already know that low-dose CT is a valuable tool for reducing mortality rates, but now there’s evidence that it might reduce financial costs as well. A new analysis of the 2010 National Lung Screening Trial (NLST) shows that low-dose CT is a cost-effective diagnostic tool for patients at high-risk of lung cancer, according to AuntMinnie.com.

The Medical Imaging and Technology Alliance (MITA) released a statement saying the organization welcomes the analysis and “looks forward to ongoing collaboration with patient advocates and others in the imaging community to ensure access to this lifesaving technology.”

In my opinion, though, the key question in whether low-dose screening for lung cancer is cost effective is: what is the cost of working up the false positives? That cost needs to be subtracted from the cost benefit of the lives saved. This new analysis suggests that low-dose screening is indeed cost effective. One thing no cost analysis considers: the value of a negative exam to a very worried patient.

Further new twist: we now can do ultra-low-dose lung cancer screening using fully model-based iterative reconstruction techniques. This technique enables a 60 percent radiation dose reduction (down to the sub-0.5 mSv range) below that of even recent low-dose CT – further substantially decreasing any downside from lung cancer screening in high-risk patients.

CT Lung Screening and Follow-up Protocol

Research published in this month’s American Journal of Roentgenology reported excellent results on a protocol for working up patients with nodules found in CT lung screening. Ever since the National Lung Screening Trial showed a 20% mortality reduction among high-risk patients screened for the disease, criticism has been vocalized due to the potentially large number of false-positive results following diagnostic imaging investigations. Though the possibility of finding cancer outweighs the risk of false positives, the researchers argued that false-positive results could potentially increase the risks and costs of screening, diminishing the benefit of early cancer detection.

This study, which required participants without a history of cancer to have smoked a minimum of 10 pack-years, concluded with positive results. According to the research, the algorithm produced low false-positive rates, and could make the establishment of large-scale CT screening programs more feasible.

Follow-up CT protocols in lung cancer screening – once a finding is discovered and needs to be evaluated over time or even just routinely on a schedule – is one area ripe for ultra low-dose CT technique. With this technique, we really can see doses reduced by 40 – 80% among these applications! Accepting higher noise in images, very low-dose kVp (in the 80-100 range), and aggressive application of iterative reconstruction techniques can produce diagnostic CT results at breathtakingly low doses.

NCCN Confirms Importance of Lung Cancer Screening

Recently, the National Comprehensive Cancer Network has come forward in favor of lung cancer screening with low-dose CT. The NCCN is the first professional organization to perform the comprehensive review and update their recommendations to promote lung cancer screening.

This update further validates the key concept that high risk patients benefit from screening. High risk patients for lung cancer diagnoses are those who are multiple pack year smokers for 25 of more years. For these individuals, low- dose CT screening reduces the number of lung cancer deaths by 20 percent.

While we don’t really know the full cost of a screening program – such as the costs of working up false positive CT findings,  the benefit in lives saved seems to justify considering screening now.

Fortunately, the CT technique for screening is low dose and involves low radiation dosage.