Overkill.

Longer 5-year follow up analysis of the Danish Lung Cancer Screening Trial (DLCST) demonstrates an unsettling rate of “overdiagnosis.” As a reminder, the DLCST randomized >4K smokers to 5 years of annual low-dose CT-screening versus no screening to demonstrate triple the rate of detection with screening. Sounds great, but how many of those “extra” catches were clinically meaningful? When it comes to lung cancer, you’d think all of them. But one way to test this is to see if excess advanced stage cancers become apparent in the control arm following study completion, as would be expected after clinically meaningful misses. In the 5 years after study completion, 27 and 29 lung cancers were diagnosed in the screening and no screening arms, respectively. When taken together with the screening years, there were a total of 96 versus 53 lung cancers detected, respectively, translating to a 67% rate of overdiagnosis. TBL: Not all lung cancers are destined to cause problems, shedding a new light on lung cancer screening trials. | Patz, JAMA Intern Med 2018