Purpose: Ovarian cancer is the 7th leading cancer diagnosis and the 8th leading cause of cancer death in women worldwide. We conducted this study to investigate the incidence of ovarian cancer internationally.
Methods: The trends in ovarian cancer incidence were analyzed through the latest data of CI5 over the 40-year period from 21 populations in 4 continents using Joinpoint analysis, ASRs and proportions of different histological subtypes in those populations were also analyzed using volume XI of CI5.
Results: ASRs of ovarian cancer were from 7.0 to 11.6 per 100,000 in non-Asia populations during 2008-2012. In Asia, the ASR in Israel (Jews) were the highest, up to 8.1 per 100,000 in the same period. The international trends from 1973 to 2012 showed that ASRs of ovarian cancer were decreasing in 8 of 21 selected populations, whereas ASRs in Slovakia, Spain (Navarra) and China (Shanghai) were increasing. Meanwhile, there are certain differences in the main pathological classification patterns within different regions. In Asia, China (Hong Kong) and Japan both have a higher ASRs and proportions for clear cell and endometrioid carcinomas, while Japan has the highest ASRs and proportions for mucinous carcinomas.
Conclusion: Although the reasons for those trends were not entirely clear, environmental, reproductive and genetic factors were likely to have led to these patterns. Meanwhile, more attention and further study should be given to the etiological factors of histology-specific ovarian cancer.
Keywords: Age-standardized incidence rates; Average annual percentage change; Histologic subtype; International trends; Joinpoint analysis; Ovarian cancer.