Our study is a cross-sectional analysis within current smokers in the PLCO Cancer Screening Trial. PLCO, described in detail elsewhere [17, 18], is a large multicenter randomized screening trial for four cancer sites. Briefly, PLCO randomized over 150,000 men and women aged 55–74 in ten screening centers across the US between 1993 and 2001. PLCO eligibility criteria included no history of cancers of the prostate, lung, colorectum, or ovaries.
