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It is rare to find laryngeal cancer in individuals who do not
smoke and drink, with limited information on risk factors for
such individuals. In the USA a hospital based case-control study
found an association between smoking in teetotallers and moderate
drinkers, but did not provide any data on non-smokers. Other case-control
studies have reported an increased risk of laryngeal cancer for
non-smoking drinkers and non-drinking smokers, however the data
was based on small sample sizes. This paper by Bosetti C et al,
is an analysis of the separate effect of alcohol and tobacco on
laryngeal cancer risk. Pooled data of 2 case-control studies (one
conducted between 1986-1992 in northern Italy and one conducted
between 1992-2000 in northern Italy and the Swiss canton of Vaud)
were used to analyses the separate effects of smoking and alcohol
use on laryngeal cancer risk and included large numbers of non-drinking,
non-smoking subjects.
Subjects were 40 non-smoking and 68 non-drinking cases of incident,
histologically confirmed laryngeal cancer and 160 non-smoking
and 161 non-drinking controls admitted to the same network of
hospitals for acute, non-neoplastic conditions. A questionnaire
was used to ascertain demographics, anthropometric variables and
various life-style characteristics including smoking and alcohol.
The multivariate odds ratio (OR) for laryngeal cancer was 2.46
(95% CI 0.98 — 6.20) for non-smoking heavy drinkers (> 8 drinks/day
compared to < 8 drinks/day). There was no evidence for an elevated
risk at lower drinking levels; when the reference category was
set at <3 drinks/day, the OR was below unity until 7 drinks/day,
and the trend in the risk was significant. In non-drinkers, the
OR was 9.38 (95% CI 3.35-26.26) for current smokers and 4.23 (95%
CI 1.41 — 12.73) for ex-smokers, as compared to never smokers.
The OR increased with increasing number of cigarettes smoked per
day (P= 0.004 for trend) and was 13.56 (95% CI 3.90-47.19) for
>25 cigarettes/day. Even in non-smokers the uniquely large data
set confirms a strong role of tobacco in the risk for laryngeal
cancer. Alcohol abuse also appears to increase the risk, even
in non-smokers. In contrast with cancers of the oral cavity and
oesophagus, no excessive risk was found for moderate drinking.
Source. Bosetti C, Gallus S, Franceschi S et al. Cancer of the
larynx in non-smoking alcohol drinkers and in non-drinking tobacco
smokers. BR J Cancer 87 (2002) 516-518. |
