Purpose: In this study, we aimed to investigate trends in the age-standardized and age-specific incidence rates in two distinct regions (the northern and southern areas) of South Africa covered by a population-based cancer registry. In addition, trends in coverage of the cervical cancer screening program were assessed using routine health service data.
Methods: Occurrences (topography C53.0-C53.9) for the period 1998-2012 were extracted from a cancer registry database from which basic descriptive statistics and frequencies were analyzed for all variables using CanReg4. Trends over time were estimated using a direct standardization method and world standard population as a reference. Screening coverage annualized figures for women age ≥ 30 years by sub-health district were extracted from the District Health Information System.
Results: In the northern area, annual age-standardized incidence rates per 100,000 women increased from 24.0 (95% CI, 21.1 to 27.0) in 1998-2002 to 39.0 (95% CI, 35.6 to 42.5) in 2008-2012, with a screening coverage rate of 15% by 2012. In contrast, no increase was observed in incidence in the southern area, with rates of 20.0 (95% CI, 18.5 to 21.4) in 1998-2002 and 18.8 (95% CI, 16.2 to 21.4) in 2008-2012, and the southern area had a higher screening coverage of 41% in 2012. Overall, the percentage distribution of stage at diagnosis showed that 28.5% of occurrences were diagnosed at disease stages I and II and 35%, at III and IV; 36% had with missing stage information (2003-2012). In 77% of occurrences, a histologically verified diagnosis was made, compared with only 12.3% by cytology.
Conclusion: This study has demonstrated an almost two-fold increase in the incidence rate in the northern area but little change in the southern area of the cancer registry.