Lung cancer in never-smokers – what are the differences?

Abstract

Never-smokers with NSCLC present distinct demographic and clinical characteristics. The characteristics of tumor also differ between never-smokers and ever-smokers, which may suggest different carcinogenic pathways.

Clinical characteristics and survival in non-small cell lung cancer patients by smoking history: a population-based cohort study

“…The overrepresentation of women in this group is also confirmed [7][8][9][10][11][12][14][15][16][17][18][20][21][22]24,26], and supports the notion of the presence of sex-based differences either in vulnerability to non-tobacco associated lung cancer or in exposure to other risk factors, such as environmental tobacco smoke. Due to observed sex imbalances, there has been considerable interest surrounding the possible role of oestrogen [6,9,34,35].…”

“…The observed higher proportion of both younger (<50 years) and older patients (80 years) among never-smoking has, to the best of our knowledge, never been observed before. However, there have also been reports of no differences in age and also the opposite, i.e., a younger age at diagnosis among never-smokers [7][8][9][10]14,15,[17][18][19][20][21][22]26]. None of the studies reporting an older age for never-smokers included an East Asian population.…”

“…Several studies of different size and design have compared clinical lung cancer characteristics in never-smokers with that of ever-smokers, including assessments of survival . Most of these studies were hospital-based with data from only a small number of hospitals and the majority included less than 2000 lung cancer patients [8,10,12,[15][16][17][18][20][21][22]24,26]. Despite inconsistencies between studies, the collective evidence indicates that the pathogenesis and tumour biology of lung cancer differ by smoking history.…”

Ambient PM 2.5 exposure and risk of lung cancer incidence in North America and Europe

“…Consequently, lung cancer in never smokers is ranked as the seventh leading cause of cancer mortality. The most recent literature on non-small cell lung cancer indicates that the overall incidence of lung cancer within this non-smoking population is increasing [5][6][7][8][9]. While there is some conflicting evidence on lung cancer rates in non-smokers [10][11][12][13][14], it is becoming increasingly important to understand the risk factors, other than smoking, that contribute to incident lung cancer [8,15].…”

Lung cancer in young women in southern Sweden: A descriptive study

“…A number of oncogene mutations have been described in lung cancer. Particularly among never‐smokers with adenocarcinoma, several of these mutations, especially in the ALK and EGFR genes, are prevalent to a greater extent than among ever‐smokers, suggesting that these mutations are highly predisposing for lung cancer, and while we do not here have the genetic profile of the lung cancer cases in our material, we believe that a similar pattern could be seen in our material had the mutation status been known, with a high prevalence of these mutations, particularly among never‐smokers with adenocarcinoma.…”