Independent and combined effects of tobacco smoking, chewing and alcohol drinking on the risk of oral, pharyngeal and esophageal cancers in Indian men.
Oral, pharyngeal and esophageal cancers are 3 of the 5 most common cancer sites in Indian men. To assess the effect of different patterns of smoking, chewing and alcohol drinking in the development of the above 3 neoplasms and to determine the interaction among these habits, we conducted a case-control study in Chennai and Trivandrum, South India. The cases included 1,563 oral, 636 pharyngeal and 566 esophageal male cancer patients who were compared with 1,711 male disease controls from the 2 centers as well as 1,927 male healthy hospital visitors from Chennai. We observed a significant dose-response relationship for duration and amount of consumption of the 3 habits with the development of the 3 neoplasms. Tobacco chewing emerged as the strongest risk factor for oral cancer, with the highest odds ratio (OR) for chewing products containing tobacco of 5.05 [95% confidence internal (CI) 4.26-5.97]. The strongest risk factor for pharyngeal and esophageal cancers was tobacco smoking, with ORs of 4.00 (95% CI 3.07-5.22) and 2.83 (95% CI 2.18-3.66) in current smokers, respectively. An independent increase in risk was observed for each habit in the absence of the other 2. For example, the OR of oral cancers for alcohol drinking in never smokers and never chewers was 2.56 (95% CI 1.42-4.64) and that of esophageal cancers was 3.41 (95% CI 1.46-7.99). Furthermore, significant decreases in risks for all 3 cancer sites were observed in subjects who quit smoking even among those who had quit smoking 2-4 years before the interview.
Znaor
Ariana
A
Unit of Environmental Cancer Epidemiology, International Agency for Research on Cancer, 150 cours Albert-Thomas, 69372 Lyon cedex 08, France.
Brennan
Paul
P
Gajalakshmi
Vendhan
V
Mathew
Aleyamma
A
Shanta
Viswanathan
V
Varghese
Cherian
C
Boffetta
Paolo
P
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000428:Alcohol Drinking / Q000009:adverse effects*; D002294:Carcinoma, Squamous Cell / Q000453:epidemiology / Q000209:etiology; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D004522:Educational Status; D004938:Esophageal Neoplasms / Q000453:epidemiology* / Q000209:etiology; D006184:Habits; D006801:Humans; D007194:India / Q000453:epidemiology; D016013:Likelihood Functions; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000453:epidemiology* / Q000209:etiology; D010610:Pharyngeal Neoplasms / Q000453:epidemiology* / Q000209:etiology; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*; D016540:Smoking Cessation; D014030:Tobacco, Smokeless / Q000009:adverse effects*