Relative impact of earlier diagnosis and improved treatment on survival for colorectal cancer: A US database study among elderly patients

Highlights • Improvements in screening were associated with migration of cancer toward earlier stage. • Improvements in screening and chemotherapy were translated into real world effectiveness. • Changes toward earlier tumor stage and smaller size contributed to 20% of survival increase. • Survival increase was largely explained by improvements in chemotherapy (≥71.6%). • Other treatment-related factors also contributed to survival increase (25%).