CHAPTER 1 Smoking Cessation 2

annual number of deaths from breast, colon, and
prostate cancer combined [15]. Recent advances in
technology have enabled earlier diagnoses, and ad-
vances in surgery, radiation therapy, imaging, and
chemotherapy have produced improved responses
rates. However, despite these efforts, overall sur-
vival has not been appreciably affected in 30 years,
and only 12–15% of patients with lung cancer are
being cured with current treatment approaches
[16]. The prognosis of lung cancer depends largely
on early detection and immediate, premetastasis
stage treatment [17]. Prevention of lung cancer
is the most desirable and cost-efficient approach
to eradicating this deadly condition. Numerous
epidemiologic studies consistently define smoking
as the major risk factor for lung cancer (e.g. [18–
20]). The causal role of cigarette smoking in lung
cancer mortality has been irrefutably established
in longitudinal studies, one of which lasted as long
as 50 years [21]. Tobacco smoke, which is inhaled
either directly or as second-hand smoke, contains
an estimated 4000 chemical compounds, including
over 60 substances that are known to cause cancer
[22]. Tobacco irritants and carcinogens damage the
cells in the lungs, and over time the damaged cells
may become cancerous. Cigarette smokers have
lower levels of lung function than nonsmokers
[9,23], and quitting smoking greatly reduces
cumulative risk for developing lung cancer [24].
The association of smokingwith the development
of lung cancer is the most thoroughly documented
causal relationship in biomedical history [25]. The
link was first observed in the early 1950s through
the research of Sir Richard Doll, whose pioneering
research has, perhaps more so than any other epi-
demiologist of his time, altered the landscape of dis-
ease prevention and consequently saved millions of
lives worldwide. In two landmark US Surgeon Gen-
erals’ reports publishedwithin a 20-year interval (in
1964 [26] and in 2004 [9]), literature syntheses fur-
ther documented the strong link between smoking
and cancer. Compared to never smokers, smokers
have a 20-fold risk of developing lung cancer, and
more than 87% of lung cancers are attributable to
smoking [27]. The risk for developing lung cancer
increases with younger age at initiation of smoking,
greater number of cigarettes smoked, and greater
number of years smoked [11].Women smoking the
same amount as men experience twice the risk of
developing lung cancer [28,29].