Trends in net survival for 1,834,894 patients with cancer from 16 population-based cancer registries in Japan, 2000-14 (CONCORD-3).

[BACKGROUND] In 2018, CONCORD-3 updated long-term surveillance of cancer survival trends worldwide. In this monograph, we conducted further analyses and examined trends in net survival using the Japanese data during 2000-14.

[METHODS] Sixteen population-based cancer registries in Japan contributed data to CONCORD-3 with anonymized individual records on 2 237 861 patients diagnosed with one of 15 adult cancers (15-99 years), and brain tumors and hematological malignancies in children (0-14 years). Five-year net survival was estimated with the Pohar Perme estimator and age-standardized with International Cancer Survival Standard weights. We estimated survival for three calendar periods, by age group, sex, anatomic site or morphology, and by stage at diagnosis.

[RESULTS] Five-year net survival improved between 2000-04 and 2010-14 for several cancers, including brain tumors (27.9%-46.3%), ovarian cancer (35.5%-46.3%), stomach cancer (50.5%-60.3%), lymphoid malignancies (47.5%-57.3%), myeloid malignancies (24.8%-33.3%), and esophageal cancer (27.7%-36.0%). Breast cancer, childhood lymphoma, and prostate cancer showed consistently high or improving survival (85.9%-93.0%). In contrast, survival for melanoma remained unchanged. Net survival was low for pancreatic cancer (6.9%-8.3%). Among selected countries, survival was higher in Japan for esophageal (36.0%), liver (30.1%), and lung cancers (32.9%). Survival for melanoma, hematologic malignancies, and childhood cancers was lower in Japan than in Western countries.

[CONCLUSIONS] Net survival in Japan improved substantially for several cancers, but survival for pancreatic cancer remained low. International collaboration is crucial to accelerate the development of effective cancer control strategies.