Cigarette smoking and risk of pancreatic cancer: a clinic-based case-control study in the San Francisco Bay Area

PurposeCigarette smoking is an established risk factor for pancreatic cancer (PC). We examined the association between cigarette smoking and PC in a San Francisco Bay Area clinic-based, case-control study.MethodsA total of 536 cases and sex and age frequency-matched controls (n = 869) were recruited predominately from the University of California San Francisco (UCSF) medical clinics between 2006 and 2011. Participants were interviewed in-person using structured questionnaires. Adjusted odds ratios (ORs) were computed.ResultsForty-eight percent of cases and controls reported never having smoked cigarettes; 39% of cases and 40% of controls were former smokers; 13% of cases and 12% of controls were current smokers. No association was found for either former (OR = 0.85, 95% confidence interval [CI] = 0.66–1.1) or current cigarette smoking (men: OR = 1.0, 95% CI = 0.60–1.7; women: OR = 1.2, 95% CI = 0.73–2.1). No dose-response relationships were detected with number of cigarettes/day, smoking intensity, duration, or years since last smoked. Comparisons with a 1995–1999 population-based UCSF study demonstrated a significantly increased proportion of never smokers in this study (P < .001).ConclusionsThis study revealed no significant associations between cigarette smoking and PC in the San Francisco Bay Area during 2006–2011. Data suggest a reduction in the duration of smoking within the referral population.