The carcinogenicity of cigar and pipe smoking is established but the effect of detailed smoking characteristics is less well defined. We examined the effects on cancer incidence of exclusive cigar and pipe smoking, and in combination with cigarettes, among 102,395 men from Denmark, Germany, Spain, Sweden and the United Kingdom in the EPIC cohort. Hazard ratios (HR) and their 95% confidence intervals (CI) for cancer during a median 9-year follow-up from ages 35 to 70 years were estimated using proportional hazards models. Compared to never smokers, HR of cancers of lung, upper aerodigestive tract and bladder combined was 2.2 (95% CI: 1.3, 3.8) for exclusive cigar smokers (16 cases), 3.0 (2.1, 4.5) for exclusive pipe smokers (33 cases) and 5.3 (4.4, 6.4) for exclusive cigarette smokers (1,069 cases). For each smoking type, effects were stronger in current smokers than in ex-smokers and in inhalers than in non-inhalers. Ever smokers of both cigarettes and cigars [HR 5.7 (4.4, 7.3), 120 cases] and cigarettes and pipes [5.1 (4.1, 6.4), 247 cases] had as high a raised risk as had exclusive cigarette smokers. In these smokers, the magnitude of the raised risk was smaller if they had switched to cigars or pipes only (i.e., quit cigarettes) and had not compensated with greater smoking intensity. Cigar and pipe smoking is not a safe alternative to cigarette smoking. The lower cancer risk of cigar and pipe smokers as compared to cigarette smokers is explained by lesser degree of inhalation and lower smoking intensity.
2010. Vol. 127, no 10, 2402-2411 p.