Lung cancer survival in Switzerland by histology, TNM stage and age at diagnosis

In 2017, more than 3 out of 100 deaths worldwide were attributed to lung cancer, making it the deadliest malignancy [1]. In Switzerland, it is the second most frequent cancer among men and the third most frequent among women. Every year, 4,400 individuals are diagnosed with lung cancer and 3,200 die of it [2]. A well-established risk factor is smoking. Indeed, lung cancer risk is on average 5-10 times higher among smokers compared to nonsmokers [3]. The differences in smoking habits between men and women influenced the evolution of lung cancer incidence over the last century. Men started smoking in large numbers already in the early 1900’s, while among women smoking became more common later in the century. In recent years, a decrease in incidence and mortality rates in developed countries has been observed among men but not among women [4, 5]. Today lung cancer is still more common among men than among women (incidence ratio 1.8:1) [6]. Despite smoking’s major role in lung carcinogenesis, approximately 10-15% of all cases occur in never-smokers. Second-hand smoke, radon gas, air pollution, exposure to occupational agents and genetic predisposition are the main risk factors to which these cases are attributed [7]. Late diagnosis and limited treatment reduce the chances of lung cancer survival. In Europe, lung cancer survival five years after diagnosis was reported to be, on average, lower than 15% [8]. However, a number of factors must be taken into account in order to correctly predict the prognosis of a lung tumour. Survival has been shown to be considerably worse among patients suffering from small cell lung cancer (SCLC) compared to those with non-small cell histology (NSCLC) [9]. Moreover, as for other cancers, the tumour stage at time of diagnosis weighs substantially on the treatment options and their success. Finally, women are known to have a better survival than men and the elderly a worse prognosis compared to younger individuals [10-12]. In the present study, we update our previously published lung cancer survival data [13] for the period 2011-2015 and we extend estimation of survival to ten years after diagnosis. Moreover, we present for the first time survival following lung cancer in Switzerland by histological subgroup, UICC TNM stage and age group