The group, led by Dr. Bradley Allen from the University of Wisconsin-Madison, developed a Markov model to simulate the accuracy and costs associated with lung cancer screening using either CT or MRI. They decided to explore MRI as a possible substitute for CT due to its potential to minimize the false-positive rate associated with CT lung screening.
The model incorporated information regarding lung cancer incidence and mortality, as well as published data on the sensitivity and specificity of detecting lung nodules on CT and MRI scans. It also assumed that the cohort would consist of 60-year-old men who had a smoking history of two packs per day for 20 years.
"By using a mathematical model, we sought to determine if the use of lung MRI for the primary screening of at-risk individuals could be a better value proposition for patients and healthcare systems," Allen told AuntMinnie.com.
After simulating both scenarios with their model, the researchers found that the total estimated life years per patient were nearly equivalent when screening with CT or MRI. However, the model also showed that MRI offered a net monetary benefit of several thousand dollars, despite the higher cost of the exam itself.
This result was driven largely by the improved specificity of MRI for characterizing solid nodules -- leading to a significant decrease in downstream workup costs, Allen said.