Differences between colon and rectal cancer in complications, short-term survival and recurrences

PURPOSE: Many apparent differences exist in aetiology, genetics, anatomy and treatment response between colon cancer (CC) and rectal cancer (RC). This study examines the differences in patient characteristics, prevalence of complications and their effect on short-term survival, long-term survival and the rate of recurrence between RC and CC. METHODS: For all stage II–III CC and RC patients who underwent resection with curative intent (2006–2008) in five hospitals in the Netherlands, occurrence of complications, crude survival, relative survival and recurrence rates were compared. RESULTS: A total of 767 CC and 272 RC patients underwent resection. Significant differences were found for age, gender, emergency surgery, T-stage and grade. CC patients experienced fewer complications compared to RC (p = 0.019), but CC patients had worse short-term mortality rates (1.5 versus 6.7 % for 30-day mortality, p = 0.001 and 5.2 versus 9.5 % for 90-day mortality, p = 0.032). The adjusted HR (overall survival) for CC patients with complications was 1.57 (1.23–2.01; p < 0.001) as compared to patients without complications; for RC, the HR was 1.79 (1.12–2.87; p = 0.015). Relative survival analyses showed high excess mortality in the first months after surgery and a sustained, prolonged negative effect on both CC and RC. Complications were associated with a higher recurrence rate for both CC and RC; adjusted analyses showed a trend towards a significant association. CONCLUSION: Large differences exist in patient characteristics and clinical outcomes between CC and RC. CC patients have a significantly higher short-term mortality compared to RC patients due to a more severe effect of complications.