Introduction

Lung cancer is the leading cause of cancer death in the world; over 1.3 million worldwide deaths were recorded in 2008. These statistics are astounding given the rarity of lung cancer during the first half of the twentieth century, when lung cancer had a lower incidence than liver, prostate, colon, stomach, uterine, breast and even ovarian cancer. Only a sound understanding of the complex epidemiological, etiological, and molecular-pathological aspects of lung carcinoma will enable clinical and scientific progress against this deadly disease, regardless of technological advances. This chapter aims to elucidate the epidemiological, etiological and clinical aspects of lung cancer.

Incidence and mortality

Lung cancer is the most common and deadliest cancer in the world. Estimated numbers of lung cancer cases worldwide increased 51% since 1985. The incidence information is collected routinely by cancer registries and expressed as an absolute number of cases per year or as a rate per 100 000 persons per year. The latter provides an approximation of the average risk of developing a cancer. Excluding non-melanoma skin cancer, approximately 7.5 million people died of cancer worldwide in 2008. Of these deaths 1.37 million were lung cancer deaths (20%). The worldwide incidence of lung carcinoma in 2008 reached 1 608 823 cases, representing 12.7% of newly diagnosed cancer cases.