Tobacco and Public Health - TCSC Indonesia

Cigar, pipe, and chewing tobacco
While cigarette smoking remains the most common form of tobacco in westernized
countries, alternative forms of tobacco are available. In particular, cigars
became increasingly fashionable since mid-1990s in the United States and later
in western Europe. The number of cigars consumed in the United States increased
by approximately 50% between 1993 and 1998 (U.S. Department of Agriculture 1996,
1999). Still, little is known about the health hazard of cigar smoking, possibly because
cigars were not required to carry a health warning from the Surgeon General until June
26, 2000 (U.S. Department of Health and Human Services 2000).
Most of the published case–control studies did not have sufficient statistical
power to assess the association between either cigar, pipe, chewing tobacco, or oral
snuff consumption and pancreatic cancer on their own. These forms of tobacco
are less common and are often consumed in addition to cigarettes making difficult
the evaluation of the effect of each single product. Still, in an hospital-based study of
484 male and female patients with pancreatic cancer and 954 control subjects, pipe or
cigar smokers had a two-fold risk of developing pancreatic cancer (OR = 2.1; 95%
CI= 1.2–3.8) while the risk was 3.6 (95% CI, 1.0–12.8) for tobacco chewers
(Muscat, 1997). These results suggest that tobacco smoke causes pancreatic cancer
when inhaled into the lungs and that tobacco juice may also cause pancreatic
cancer when ingested or absorbed through the oral cavity. In a recent analysis
of a large prospective mortality study in the United States, a significant association
between cigar consumption and pancreas cancer was found but limited to current
cigar smokers who reported that they inhaled the smoke (RR = 2.7; 95% CI=1.3–9.9)
(Shapiro et al. 2000).
Gene–environment interaction
PATRICK MAISONNEUVE 481
Research in the area of gene–environment interaction is an important topic for various
cancers because minimizing exposure to environmental risk factors could reduce the
impact of inherited genetic susceptibility factors. A positive family history of pancreatic
cancer and smoking are two independent risk factors, each of which approximately
doubles the risk of pancreatic cancer but Schenk et al. found an interaction between
these two risk factors (Schenk et al. 2001). Smokers who are related to a person who
develops pancreatic cancer before the age 60 have 8 times the risk of pancreatic cancer
as individuals lacking these two risk factors.
Another report focused on the impact of smoking in patients with hereditary
pancreatitis, a rare pancreatic disorder associated with a 50- to 70-fold increased risk of
pancreatic cancer (Lowenfels et al. 2001). In these patients, smoking doubled the
risk of pancreatic cancer, as it does in the general population, but pancreatic cancer
developed in average 20 years earlier in smokers than in non-smokers.