Genetic testing
The accelerating decline in NSCLC mortality starting in 2013 corresponds to the period in which clinicians began to routinely test for molecular alterations in epidermal growth factor receptor (EGFR) and anaplastic lymphoma kinase (ALK), the authors pointed out.
In 2012, the National Comprehensive Cancer Network recommended that all patients with nonsquamous NSCLC undergo genetic testing for EGFR mutations and ALK rearrangements.
At about the same time, the FDA approved a number of targeted therapies for tumors that are sensitive to targeted tyrosine kinase inhibition.
More recently, immunotherapies that act as programmed cell death inhibitors have substantially improved NSCLC outcomes, the authors noted.
The first of these was approved for NSCLC in 2015 (pembrolizumab). It was followed by a number of similar agents. It is unlikely that their approval contributed to the observed decline in NSCLC mortality, which started to accelerate in 2013 in the United States, the authors commented.
Nevertheless, the effect that the immune checkpoint inhibitors has had on the survival of patients with NSCLC can be expected to continue and to extend improvement in survival beyond the current study endpoint in 2016, they suggest.
Another contributing factor is the decline in smoking that has occurred in the United States since the 1960s. This has led to the decrease in the incidence of lung cancer. The faster decrease in the incidence of SCLC, compared with NSCLC can be explained by the higher relative risk of smoking with regard to SCLC compared to NSCLC, they commented.
Similarly, the faster decrease in lung cancer incidence in men compared to women can be explained by the relative difference in the prevalence of smoking between men and women, they added.
The authors disclosed no relevant financial relationships.
This article first appeared on Medscape.com.
