IADR Abstract Archives
Half-Century Trend and Age-Period-Cohort Effect of Oropharyngeal Cancer in Singapore
Objectives: To examine trends and age-period-cohort (APC) effects on oropharyngeal cancer incidence in Singapore between 1968 and 2017 by human papillomavirus (HPV) status
Methods: All locally diagnosed HPV-related and HPV - unrelated oropharyngeal cancer classified by tumour site and - Singapore residents’ size were extracted by age, ethnicity (Chinese, Malay and Indian) and gender from the Singapore Cancer Registry and the Department of Statistics Singapore, respectively. The trend of age-standardised incidence rate (ASIR) (per 100,000 inhabitants), using the Segi-Doll World Standards, was evaluated by Prais-Winsten regressions with Average Annual Percentage Change (AAPC) reported for each ethnicity and gender. The APC effects on HPV-related and HPV-unrelated oropharyngeal cancer aged 25-84 were assessed by Poisson regression and middle cohort as reference for each ethnicity and gender, respectively.
Results: Between 1968-2017, 1618 HPV-related and 2977 HPV-unrelated oropharyngeal cancer were diagnosed, with the average ASIR highest in Indians (Indian=6.93, Chinese=2.81, Malay=1.81). The male-female ASIR ratio reduced from 5.82 (1968-1977) to 4.0 (2008-2017) for HPV-related cancers, -from 2.58 (1968-1977) to 1.52 (2007-2017) for HPV-unrelated cancers. Trend analysis detected the decrease of HPV-unrelated ASIR in males among all ethnicities (Chinese: AAPC=-0.9, Malay: AAPC=-2.7, Indian: AAPC=-2.6), but in females among Indians only (AAPC=-4.0). HPV-related ASIR decreased just among Indian females (AAPC=-5.3). The cohort born between 1983-1992 had the lowest incidence of HPV-related cancers in males but highest in HPV-unrelated cancers, compared to the reference cohort. Period effect mainly contributed to HPV-related cancer among males with increased incidence after 1988-1997. Overall, the age effect was more pronounced in males-.
Conclusions: HPV-unrelated ASIR was higher than HPV-related. There was an age effect on the overall ASIR. The cohort effect is mainly attributed to HPV-unrelated cancer incidence, while the period effect largely contributed to HPV-related cancer incidence, but only males. The only significant decrease in HPV-related ASIR was detected in Indian females.
Methods: All locally diagnosed HPV-related and HPV - unrelated oropharyngeal cancer classified by tumour site and - Singapore residents’ size were extracted by age, ethnicity (Chinese, Malay and Indian) and gender from the Singapore Cancer Registry and the Department of Statistics Singapore, respectively. The trend of age-standardised incidence rate (ASIR) (per 100,000 inhabitants), using the Segi-Doll World Standards, was evaluated by Prais-Winsten regressions with Average Annual Percentage Change (AAPC) reported for each ethnicity and gender. The APC effects on HPV-related and HPV-unrelated oropharyngeal cancer aged 25-84 were assessed by Poisson regression and middle cohort as reference for each ethnicity and gender, respectively.
Results: Between 1968-2017, 1618 HPV-related and 2977 HPV-unrelated oropharyngeal cancer were diagnosed, with the average ASIR highest in Indians (Indian=6.93, Chinese=2.81, Malay=1.81). The male-female ASIR ratio reduced from 5.82 (1968-1977) to 4.0 (2008-2017) for HPV-related cancers, -from 2.58 (1968-1977) to 1.52 (2007-2017) for HPV-unrelated cancers. Trend analysis detected the decrease of HPV-unrelated ASIR in males among all ethnicities (Chinese: AAPC=-0.9, Malay: AAPC=-2.7, Indian: AAPC=-2.6), but in females among Indians only (AAPC=-4.0). HPV-related ASIR decreased just among Indian females (AAPC=-5.3). The cohort born between 1983-1992 had the lowest incidence of HPV-related cancers in males but highest in HPV-unrelated cancers, compared to the reference cohort. Period effect mainly contributed to HPV-related cancer among males with increased incidence after 1988-1997. Overall, the age effect was more pronounced in males-.
Conclusions: HPV-unrelated ASIR was higher than HPV-related. There was an age effect on the overall ASIR. The cohort effect is mainly attributed to HPV-unrelated cancer incidence, while the period effect largely contributed to HPV-related cancer incidence, but only males. The only significant decrease in HPV-related ASIR was detected in Indian females.