Ovarian Cancer Incidence in the Multi-Ethnic Asian City-State of Singapore 1968-2012

Purpose: We investigate ovarian cancer incidence between 1968 and 2012 in Singapore, a multiethnic Asian city state.

Methods: Aggregated data of ovarian epithelial cancer numbers and estimated person-years from 1968 to 2012 were obtained from Singapore Cancer Registry. Age-Period-Cohort modelling was performed.

Results: The age-standardised incidence rate of ovarian cancer increased from 5.8 to 12.5 per 100,000 per year between 1968 and 2012, while the age-standardised mortality rate has remained stable. This increase was higher among Malays (5.1 to 14.0 per 100,000 per year), compared to Chinese and Indians. Serous carcinoma showed the greatest increase in incidence from 0.4 to 3.4 per 100,000 per year. Period effects were seen in the ovarian cancer incidence trend in Chinese women, but not Malay and Indian women. Clear cell and mucinous carcinoma subtypes were more common in Chinese than in Malay and Indian women. Stage at diagnosis for the years 2003-2010 differed by subtype, and the majority of patients with serous carcinomas presented at a later stage compared to those with clear cell or mucinous carcinomas.

Conclusion: Ovarian cancer incidence rates have doubled in 40 years in Singapore. There were ethnic differences in incidence rates and ovarian cancer subtypes.