Urothelial cancer at different tumour sites: role of smoking and habitual intake of analgesics and laxatives. Results of the Berlin Urothelial CancerStudy

Background. In Germany about 20000 new cases of urothelial cancer (UC) and about 7500 deaths from bladder cancer alone occur each year. Among the mani fold risk factors, little research has been done on the role of smoking and the habitual intake of analgesics and laxatives-practices that are common in parts of the German population. The aim of this study is to define the p roportion of risk derived from these preventable habits for the development of UC at its different sites. Subjects and methods. A case-control study in the area of the former West B erlin was performed from 1990 to 1995 including all newly diagnosed inciden t cases of UC from the eight hospitals of the study area. Study subjects: a nd population-based controls individually matched by age (+/-2 years) and s ex were evaluated by a standardized face-to-face interview about the lifelo ng exposure to cigarette smoking, analgesics, and laxatives. Adjusted risk analysis was carried out for the main exposure variables in relation to the different sites of UC in the bladder, ureter, and renal pelvis. Results. Six hundred and forty-seven cases of UC (571 bladder, 25 ureter, a nd 51 renal pelvis) and an identical number of controls were included in th e analysis (response rate in cases, 84.6%; in controls, 70.2%). Smoking inc reased the risk of bladder cancer (BC) by an odds ratio (OR) of 3.22 (95% c onfidence interval (CI) 2.29-4.52), that of ureter (URC) or renal pelvis ca ncer (RPC) together by OR 6.20 (95% CI 2.04-18.81), and that of RPC alone b y OR 5.91 (95% CI 1.47-23.66). Ex-smoking was associated with an increased risk for BC (OR 1.55, 95% CI 1.10-2.19). Intake of more than 1 kg of phenac etin in analgesic mixtures was associated with an OR of 5.28 for RPC (intak e of greater than or equal to 1kg paracetamol, OR 3.27; greater than or equ al to 1kg pyrazolones, 1.12) and 0.75 for BC (not significant). Laxatives s ignificantly increased the risk of BC (OR 2.14, 95% CI 1.26-3.63) and RPC/U RC (OR 9.62, 95% CI 1.01-91.24) in both sexes. Conclusion. Habitual risks from smoking and intake of laxatives significant ly contribute to the development of UC, especially of the renal pelvis and ureter cancer. Intake of at least 1 kg of analgesic substances (anilides, p yrazolones) as calculated from this study base is associated with increased but not significant risks for RPC. These data underline that restrictive a nd educational measurements focusing on common habits would have a strong i mpact on preventing UC in Germany.