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The relationship of “shisha” (water pipe) smoking to the risk of head and neck cancer

INTRODUCTION
There has been a recent rise in popularity of waterpipe smoking (WPS) among younger people. While it is a tobacco-related product, research on the possible deleterious effects on health and its relationship with cancer is sparse. In this paper, we evaluated the existing literature and association of WPS with head and neck cancer.


MATERIALS AND METHODS
PubMed, EMBASE, Scopus, Web of Science and grey literature from January 1990 up to and including March 2017 were searched. Two independent reviewers performed the study selection according to eligibility criteria.


RESULTS
A total of seven studies that met the eligibility criteria were included. In four studies that evaluated the associated risk of oesophageal cancer, the odds ratio (OR) ranged from 1.69 (95% CI = 0.76-3.77) to 21.4 (95% CI = 11.6-39.5). The OR for the association of WPS with nasopharyngeal cancer and oral cancer was reported to be 0.49 (95% CI = 0.20-1.43) and 4.20 (95% CI = 1.32-13.3), respectively. One study that evaluated risk in different head and neck cancers reported 2-fold OR (2.73 [95% CI = 1.65-4.41]).


CONCLUSION
On the basis of our evaluation, there is an association of WPS with head and neck cancer. However, larger studies with standardized methods are needed to identify the possible detrimental health effects of WPS more fully.