Non-Smokers' Lung Cancers Caused By Tumors Arising From Genetic Mutations, Says Study

The National Institutes of Health, a part of the U.S. Department of Health and Human Services has revealed the mystery of how lung cancer arises in people who have never been smokers and may guide the development of more precise clinical treatments. “What we’re seeing is that there are different subtypes of lung cancer in never smokers that have distinct molecular characteristics and evolutionary processes,” said epidemiologist Maria Teresa Landi, M.D., Ph.D., of the Integrative Tumor Epidemiology Branch in NCI’s Division of Cancer Epidemiology and Genetics, who led the study, which was done in collaboration with researchers at the National Institute of Environmental Health Sciences, another part of NIH, and other institutions. The genomic analyses also revealed three novel subtypes of lung cancer in never smokers, to which the researchers assigned musical names based on the level of “noise” in the tumors. The “mezzo-forte” subtype had specific chromosomal changes as well as mutations in the growth factor receptor gene EGFR, which is commonly altered in lung cancer, and exhibited faster tumor growth. This analysis shows that there is heterogeneity, or diversity, in lung cancers in never smokers.” Stephen J. Chanock, M.D., director of NCI’s Division of Cancer Epidemiology and Genetics, noted, “We expect this detective-style investigation of genomic tumor characteristics to unlock new avenues of discovery for multiple cancer types.” The study was conducted by the Intramural Research Program of NCI and National Institute of Environmental Health Sciences.