The changing face of Irish head and neck cancer epidemiology: 20 years of data.

Background: Head and neck cancer (HNC) is associated with significant morbidity and mortality, especially when high stage disease is present. The epidemiology and prognosis of HNC has changed considerably over the last 20 years.

Aims: This study aimed to examine the epidemiological trends in HNC patients over a prolonged period in Ireland.

Methods: We conducted a retrospective cohort study using 20 years of cancer registry data provided by the National Cancer Registry of Ireland. Baseline characteristics and survival statistics were thereby generated.

Results: 10,148 patients were identified. There is a growing population of young (< 50 years) and very old (> 85 years) HNC patients; 48.15% of the population was elderly (> 65 years). Oral cavity (29.8%) and laryngeal cancer (28.1%) remain the most prevalent subsites, though oral cavity cancer prevalence declined from 35.9% in 1994 to 27.5% in 2014. Oropharyngeal cancer prevalence increased from 13.6 to 22.2% over the same period. Overall 5-year survival has improved significantly to 56.8% in 2010 but there remains a disparity between the elderly and adult cohorts (42.0% vs 60.7%). 5-year survival for hypopharyngeal and oropharyngeal cancers has improved from 11.8% and 33.3% to 22.2% and 44.8%, respectively, while laryngeal and oral cavity cancer survival remains approximately stable at 58.7% and 61.5%, respectively.

Conclusion: HNC survival in Ireland has improved in line with increasing recognition of the value of multidisciplinary assessment, subspecialisation in cancer care, and targeted therapies based on tumour subsites. Survival in the elderly cohort remains poor despite increasing recognition of the challenges such cases pose.