Changing site distribution of Japanese colorectal cancer

To clarify the time trends in the characteristics of colorectal cancer, we investigated 1,286 Japanese patients with colorectal cancer who underwent a resection of the disease between 1972 and 1995 at our hospital. Based on our findings, this carcinoma tended to shift to the more proximal colon in the second 11-year period in comparison to the first 11-year period (P=0.0001). This tendency was also found in elderly patients (P=0.0001), but not in young ones. These findings thus suggest the need for targeted examinations for the early detection of the proximal colon cancer, especially in the elderly.