Trends in 5-year net survival for women diagnosed with breast, cervical or ovarian cancer in Japan, 2000-14 (CONCORD-3).

[BACKGROUND] Breast, cervical and ovarian cancers significantly affect young and middle-aged women, both physically and socially. However, relevant comprehensive stratified analyses are limited. Using Japanese data from CONCORD-3, a global cancer survival surveillance program, we analyzed long-term survival trends.

[METHODS] Data from 16 Japanese population-based cancer registries were analyzed for women diagnosed aged 15-99 years during 2000-2014 with a tumor originating in the breast, cervix uteri or ovaries. Follow-up was extended to five years post-diagnosis or until December 31st, 2014. In situ tumors and death-certificate-only registrations were excluded. Five-year net survival was estimated with the Pohar Perme estimator by calendar period of diagnosis, morphology and stage, and age-standardized with International Cancer Survival Standard weights.

[RESULTS] During 2000-2014, 5-year net survival improved for breast cancer from 85.9% (95% CI, 85.2-86.6%) to 89.4% (88.9-89.9%), for cervical cancer from 67.5% (66.3-68.7%) to 71.4% (70.4-72.3%), and for ovarian cancer from 35.5% (33.8-37.2%) to 46.3% (44.9-47.7%). Five-year survival for tumors diagnosed at a localized stage remained consistently high (>98% for breast cancer and > 90% for cervical cancer). Ovarian cancer survival varied greatly according to morphology.

[CONCLUSIONS] Five-year net survival for women with cancers of the breast, cervix, and ovary) in Japan improved during 2000-2014, and remained at a globally high level throughout this period. These gains are probably attributable to earlier detection of breast and cervical cancers and advances in multimodal treatment for all cancers. Survival for distant-stage cervical and ovarian cancers remains a challenge, underscoring the need for enhanced screening and treatment strategies.