Continued change in the distribution of colorectal carcinoma

Abstract

Background: The aim of this study was to determine whether the previously reported shift in carcinoma from the left colon to the right colon has progressed. Methods: The charts of 2169 patients admitted to one institution between 1979 and 1994 with a diagnosis of colorectal carcinoma were reviewed retrospectively. The study was divided into four equal intervals. The large bowel was divided into five regions: right, transverse, left, sigmoid and rectum. Results: Right-sided lesions increased from 20·6 to 29·9 per cent (P = 0·001) and rectal lesions decreased from 22·0 to 11·3 per cent (P = 0·0002) from the first to the fourth study interval. The frequency of transverse, left and sigmoid colon lesions remained relatively constant. Conclusion: The continuing trend of increased incidence of right-sided lesions and decreased incidence of rectal lesions was documented. Any screening examination for carcinoma requires total examination of the colon.