Socioeconomic position and stage at diagnosis of head and neck cancer - A nationwide study from DAHANCA

Background. Socioeconomic differences in survival after head and neck squamous cell carcinoma (HNSCC) are among the greatest for any malignancy. To improve our understanding of the mechanisms by which socioeconomic position influences HNSCC survival, we investigated the association between socioeconomic position and advanced stage HNSCC at diagnosis. Material and methods. Men and women with HNSCC diagnosed between 1992 and 2008 were identified in the Danish Head and Neck Cancer Group (DAHANCA) database, which contains detailed information on all cases of HNSCC treated in Denmark. Individual information on the following four socioeconomic indicators: highest attained educational level, cohabitation status, disposable income and degree of urbanisation were obtained from Statistics Denmark. For the 9683 cases on which there was full information, we estimated odds ratios (ORs) for a diagnosis of advanced stage (TNM III-IV) HNSCC in multivariate logistic regression models by site (glottic, non-glottic larynx, oropharynx, hypopharynx and oral cancer), with adjustment for age, gender, period of diagnosis, education, income, cohabitation status, degree of urbanisation and comorbidity in accordance with a causal diagram. Results. For all HNSCC sites, the ORs for advanced stage at diagnosis were increased for patients with low income and for men living alone. For glottic and oral cancers, the ORs for advanced stage HNSCC increased systematically by decreasing length of education. Increased ORs were found for hypopharynx cancer patients living in rural areas or provincial cities. Having one or more comorbid conditions was associated with an increased OR for advanced stage oral cancer but with a decreased OR for oropharynx cancer. Conclusion. In this nationwide population-based study, socioeconomic differences in stage at diagnosis were found for all HNSCC subsites. Focus on the high risk for advanced stage HNSCC among vulnerable patients may be beneficial during referral and diagnosis in order to improve HNSCC outcomes.