Objective To study the age-related trends in the incidence rates of ovarian cancer in South East England between 1967 and 1996.
Design A retrospective review of systematically collected data on ovarian cancer in South East England.
Methods Data were obtained from the Thames Cancer Registry on the numbers and rates per 100,000 population of ovarian cancer per five-year age group (0–85+) in the 30-year period from 1967 to 1996 from the 26 health authorities in the Thames region. Linear regression was performed to determine the changes in incidence rates of ovarian cancer per age group over time.
Main outcome measures The change in overall incidence of ovarian cancer in South East England, as well as the change in incidence of ovarian cancer in each five-year age groups (20–85+) in the 30-year study period.
Results There was a strong positive correlation between ovarian cancer rates and year of diagnosis in women aged ≥ 70 years, and this was particularly marked in women > 85 years of age. There was a negative correlation between rates and year of diagnosis in women aged 45–59 years. The analysis did not demonstrate a significant correlation between ovarian cancer rates and year of diagnosis in women < 44 years of age or women aged 60–69 years.
Conclusions There have been significant changes in the pattern of ovarian cancer incidence in South East England during the 30-year period studied. The observed changes in ovarian cancer incidence in younger women may, in part, be explained by known reproductive factors. The rise in ovarian cancer rates among the older age group is difficult to explain, but has important implications for the future planning and provision of cancer services.