Trends in cervical cancer mortality in Korea 1993-2002: corrected mortality using national death certification data and national cancer incidence data.

Cervical cancer is a major health problem for Korean women, accounting for 9.8% of new female cancer cases, even though incidence rates have been decreasing. The Korean cervical cancer mortality rate for 1993-2002 based on National Statistical Office data shows an increasing trend, but the actual rates are thought to have decreased by epidemiologists, clinicians and other cancer experts. To explain this gap and solve this problem, we corrected the number of cervical cancer deaths by comparing death certificate cases of unspecified uterine cancer data with the national cancer incidence databases of entire cancer registries in Korea. We used 2 different methods to make a correction. First, we considered "uterus, unspecified" deaths previously registered as "cervix, uterine" cases misclassified and added them to the cervical cancer deaths. Alternatively, we multiplied the total number of registered unspecified uterine cancer deaths by age-specific proportions of registered incident cervical cancer cases among all cancers and added the product to cervical cancer deaths. The overall corrected age-standardized cervical cancer mortality rates per 100,000 women decreased from 5.2 in 1993 to 3.9 in 2002 (estimated annual percentage change (EAPC): -4.05%, 95% CI: -4.88, -3.22). While cervical cancer mortality showed a decreasing tendency in women aged 30-69 years, it increased substantially in women aged > or =70 years (EAPC: 3.62%, 95% CI: 1.92-5.35). Results of this study will provide evidence-based foundation for the evaluation of the existing cervical cancer-screening programs.