Changes in disease pattern and treatment outcome of colorectal cancer: A review of 5,474 cases in 20 years

Background and aims: Colorectal cancer (CRC) is the third most common cause of cancer-related death in Taiwan. During the past 20 years, several advances have improved the treatment outcome and quality of life of CRC patients. The purpose of this study was to identify the changes in the clinicopathological features and outcome of CRC over this period. Materials and methods: Based on the computerized database of the Taipei Veterans General Hospital, between January 1981 and December 2000, 5,474 CRC patients were identified and divided into 2 groups based on the date of treatment (1981-1990 and 1991-2000). The clinicopathological features, outcome, and prognostic factors were analyzed and compared. Results/findings: The age at onset of cancer was 61 years in the 1980s group and 66 years in the 1990s group. The frequency of rectal tumors decreased from 50% in the 1980s group to 44% in the 1990s group. Tumor, nodes, metastasis (TNM) stage distribution, surgical mortality, and anastomosis leakage were similar in the two groups. However, the 5-year overall survival rate was better in the 1990s group (56%) than that in the 1980s group (50%, P = 0.001). For rectal cancer patients, the local recurrence rate was lower in the 1990s group (6%) than that in the 1980s group (10%, P < 0.01). In stage III CRC, the 5-year overall survival rate was significantly higher in the 1990s group (54%) than that in the 1980s group (48%, P = 0.011). TNM stage was the most important independent prognostic factor for overall and disease-free survivals, followed by differentiation grade, CEA level, and treatment period. Interpretation/conclusion: Advances in surgical technique and more standard use of chemotherapy have improved CRC outcome.