Abstract
Laryngeal cancer is the second most common head and neck cancer
worldwide, which has been considering a serious global health problem
due to the high morbidity and mortality. Tumour risk factors include the
DNA repair gene polymorphisms, but their contribution for metastasis
and/or second primary tumour development has been seldom investigated.
Objective (s): The present study evaluated the possible association
between the DNA repair gene polymorphisms and laryngeal cancer risk,
metastasis and/or second primary tumour in a hospital-based case-control
study that comprised 149 laryngeal cancer patients and 448 controls from
Heliópolis Hospital, São Paulo, Brazil. Design: The single nucleotide
polymorphisms (SNPs) of the genes XRCC1 (Arg194Trp; Arg399Gln), XPD
(Lys751Gln) and XRCC3 (Thr241Met) were analysed by TaqMan SNP Genotyping
Assays. Results: The heterozygous genotype (OR 0.63, 95% CI 0.41-0.96)
as well as the mutated homozygous genotype (OR 0.29, 95% CI 0.13-0.66)
of XRCC1 (Arg399Gln) decreased the laryngeal cancer risk, even though
none of the genes polymorphisms was associated with metastasis and/or
second primary tumour development. Conclusion: The determination of the
XRCC1 (399Gln) genotype might be applied as a molecular predictor of
laryngeal cancer among individuals who are highly exposed to cigarette
smoking carcinogens and improve the prognostic of the disease.