Lung cancer screening affects detection of Stage I and Stage IV cases

Implementing lung cancer screening at four diverse healthcare systems resulted in an 8.4 percent increase in the number of Stage I lung cancers detected and a 6.6 percent decrease in Stage IV disease, according to research published in the Journal of Thoracic Oncology, the official journal of the International Association for the Study of Lung Cancer.

Of the 3,678 individuals who were diagnosed with an incident lung cancer during the study period; 11% of these were diagnosed after initiation of lung cancer screening. As screening volume increased, the proportion of patients diagnosed with lung cancer after screening initiation also rose from 0% in Q1 of 2014 to 20% in Q3 of 2019. Lung cancer screening did not result in a significant change in the overall incidence of lung cancer between 2014 and 2018.

Stage-specific incidence rates increased for Stage I cancer and declined for Stage IV disease. The annual rate of Stage I lung cancer increased by an average of 8.4% and was accompanied by an average decline of 6.6.% in Stage IV disease. By 2018, these changes in incidence resulted in a higher rate of Stage I compared to Stage IV cancers. This migration to early-stage disease with no change in the overall incidence of lung cancer suggests that implementation of screening was achieving the desired effect of identifying early-stage lung cancers that were destined to progress to more advanced stages of the disease, and without resulting in a significant rate of overdiagnosis.

Ref:

Anil Vachani et al, Journal of Thoracic Oncology,https://www.jto.org/article/S1556- 0864(22)01553-2/fulltext.