Abstract
OBJECTIVE: On February 19, 2019, Chiemi Hori, a renowned Japanese singer, publicly announced her diagnosis of stage IV tongue cancer. The news was widely reported by the Japanese media. This study examined the association between the celebrity's tongue cancer disclosure and trends in the number of oral cancer diagnoses in the national population-based cancer registry (NCR) in Japan. METHODS: Data from the NCR were used to plot monthly changes in the number of oral cancer diagnoses from 2016 to 2019 according to sex, age, residential area (divided into five categories based on the density of dentists), cancer site, and clinical stage at initial treatment. Time trends were analyzed using Joinpoint regression. RESULTS: Between 2016 and 2019, 39,415 oral cancer cases were registered. After Ms. Hori's disclosure, oral cancer diagnoses increased significantly, while other head and neck cancers showed no significant changes. The number of oral cancer diagnoses increased from 784 in January 2019 to 1195 in March 2019 (an average monthly change rate of 8.6% from December 2018 to March 2019). CONCLUSIONS: There has been a sharp increase in the number of oral cancer diagnoses since the celebrity's disclosure. This suggests that it has raised public awareness of oral cancer.