Increasing incidence of oral cancer in Hong Kong-Who, where…and why?

BACKGROUND: Oral squamous cell carcinoma (SCC) is a lethal and deforming disease of rising incidence and global significance; 600 000 new cases are seen each year, including 40 000 in China. Despite advances in management, 50% of patients die within 5 years of diagnosis. Cancer is the leading cause of death in Hong Kong, with the Hong Kong Cancer Registry (HKCR) confirming a 2% increase in new cases each year, and oral SCC the tenth leading cause of cancer death in males. Strategies to improve clinical outcome require identification and early intervention in the "high-risk" population. Unfortunately, demographic information is limited in HKCR making it difficult to undertake accurate population-based studies. This study aimed to profile contemporaneous demographics of oral cancer within the Hong Kong population.

METHODS: Following local ethical approval, the Hong Kong Hospital Authority (HA) database was accessed to identify new cases of oral SCC diagnosed and treated during an 18-year period (January 2000 to December 2017).

RESULTS: A total of 6706 oral cavity SCC cases were identified: 4291 male and 2415 female patients (with a mean age of 64.14 years). A trend for increasing number of cases each year was seen, with most patients presenting to hospitals on the Kowloon Peninsula and Hong Kong Island. The tongue was the most commonly affected oral site in 3168 patients, with tonsil (863), buccal mucosa (539) and floor of mouth (409) less common. Mean survival time between initial diagnosis and death was 1.95 years; patients with hard palate and oropharyngeal SCC survived the shortest period, whilst labio-buccal and vestibular cases exhibited significantly longer survival (P < 0.0001).

CONCLUSION: Whilst useful HA data are available regarding age, sex, site and outcome, there is a need for further improvement in demographic profiling to characterise the "high-risk" oral cancer population in Hong Kong and to facilitate targeted early therapeutic intervention.