With the recent announcement from the Centers for Medicare & Medicaid Services (CMS) regarding counseling sessions and annual screenings for lung cancer with low-dose computed tomography (also known as low-dose CT scan) for select persons at risk, there has been much discussion about the high rate of false-positives and overdiagnosis.
The National Lung Screening Trial concluded in 2011, and more than 20% of participants involved in the low-dose CT screenings were found to have lung nodules requiring further evaluation. This often involved invasive diagnostic procedures, and unfortunately, resulted in major complications at a rate of 4.5 per 10,000 persons screened. Over 25% of the nodules further investigated were benign. In the fall of 2013, an article published in The New England Journal of Medicine determined there are predictive tools that may aid to accurately estimate the likelihood of lung nodules found on the first CT scan screening for malignancy.
Two cohorts were studied, which included 2,961 participants. Of these participants, a total of 12,029 nodules were detected via initial low-dose CT scans, and 144 of these nodules were determined to be malignant. Predictors of lung cancer included older age, female gender, family history of lung cancer, emphysema, larger nodule size (>10mm to <20mm in size), location of nodule residing in either upper lobe, non-solid or ground-glass opacity, solid or part-solid in characteristic, and lower overall nodule count. Spiculation was an identified predictor in one of the cohorts studied, but not tracked in the other cohort.
Some interesting results were that the largest nodule size did not equate a greater risk for malignancy. Same with the number of nodules--more nodules present did not necessarily indicate more cancer.
Another beneficial outcome to this article--and the studies it highlighted--was the development of nodule risk-predictive models paired with calculators in order to improve clinical practice and public health. These tools aid in the 6-year lung cancer risk determination, and can be accessed if the user meets certain criteria.
Have you seen any of these calculators used at your own facility for this population? If so, were they determined to be accurate?