Oral cancer in Australia: Rising incidence and worsening mortality

Abstract

Background: Oral cancer, predominantly squamous cell carcinoma (SCC), is a lethal and deforming disease of rising incidence. Although largely preventable by eliminating harmful tobacco and alcohol risk factor behaviour, 5-year survival rates remain around 50%, primarily due to late presentation of advanced stage disease. Whilst low socio-economic status, regional and remote location and indigenous status are associated with head and neck cancer in general, detailed incidence and demographic data for oral SCC in Australia are limited. This study aimed to characterise the Queensland population at risk of oral SCC development.

Methods: Following ethical approval, the Queensland Cancer Register (QCR) dataset was analysed to determine patterns of incidence, anonymised patient demographics, clinical presentation and outcome data for oral SCC cases diagnosed between 1982 and 2018.

Results: Data from 9887 patients were obtained. Mean age at diagnosis was 64.55 years, with a male-to-female ratio of 2.51:1; males were diagnosed at a younger age (p < 0.001). At study census date, 59% of patients had died, with females demonstrating longer mean survival (p < 0.001). Clinicopathological data confirmed that SCC most commonly arose from tongue sites (49%) and, whilst tumours were predominantly moderately differentiated in nature (63%), patients with poorly differentiated carcinomas exhibited shortest survival times (p < 0.05). Over the 36-year study period, the number of diagnoses increased 4.49-fold, whilst the number of deaths increased 19.14-fold.

Conclusion: Oral SCC poses a significant and growing healthcare problem in Queensland. In the absence of national screening, characterising the high-risk oral SCC population facilitates pragmatic opportunities to raise disease awareness, to deliver targeted screening and effective primary prevention strategies, and to provide early interventional treatment intervention to reduce disease mortality and morbidity.

Keywords: oral squamous cell carcinoma; risk factors.