Jpn J Clin Oncol. 2026 Mar 20;56(Supplement_1):i34-i43. doi: 10.1093/jjco/hyaf091.
ABSTRACT
BACKGROUND: We aimed to assess 15-year trends in the 5-year net survival for patients with colon or rectal cancer from 2000 to 2014 and registered in the 16 Japanese regional population-based cancer registries included in the CONCORD-3 study.
METHODS: Data were included for adults (15-99 years) diagnosed with a cancer of the colon or rectum from 2000 to 2014 and followed up until 31 December 2014. We estimated the 5-year net survival by anatomic site, age, and stage using the Pohar Perme estimator. Age-standardized net survival was estimated using the International Cancer Survival Standard weights.
RESULTS: We analyzed data on 247 682 and 102 776 patients with colon and rectal cancer, respectively. Age-standardized 5-year net survival increased from 63.4% (95% CI: 62.7%-64.0%) in 2000-2004 to 67.8% (67.3%-68.4%) in 2010-2014 for colon cancer and from 58.6% (57.6%-59.5%) to 64.8% (64.0%-65.7%) for rectal cancer over the same period. For both cancers, survival was lower for older patients (75-99 years) than other age groups. Five-year net survival was lower for right-sided than left-sided colon cancer. Five-year net survival was higher than 90% for localized cancers of both the colon and rectum throughout 2000-2014. Survival for regional and distant disease for both cancers improved.
CONCLUSIONS: For both colon and rectal cancers, the 5-year net survival improved from 2000 to 2014. However, no improvement was noted for older patients. These results may serve as evidence for developing new cancer control measures and treatment strategies, with a focus on older patients.
PMID:41859884 | DOI:10.1093/jjco/hyaf091