Background: The aim of this study was to clarify the characteristics of recurrence and the effectiveness of surveillance tools after curative resection for colorectal cancer.
Methods: We enrolled 5230 consecutive patients (stage I, 1367; stage II, 1912; stage III, 1951) who underwent curative resection at 14 hospitals from 1991 to 1996. All patients were followed up intensively, and their outcomes were investigated retrospectively.
Results: Of the 5230 patients, 906 developed recurrence. The recurrence rates of stage I, II, and III cancers were 3.7%, 13.3%, and 30.8%, respectively (P < .0001). The curves of the cumulative appearance rate of recurrence in stage II and III patients showed a rapid increase for the first 3 years. Recurrence after 5 years was less than 1% in each stage. Clinical visits combined with measurements of tumor markers detected the majority of recurrences except in the case of lung metastasis. In contrast, 43.4% of hepatic recurrences were detected by liver imaging, and 48.4% of pulmonary recurrences were noted by chest x-ray. The 5-year survival rates after primary colorectal surgery in patients who underwent resection for recurrence were better than in those without resection: 55% vs 11% in hepatic recurrence, 68% vs 13% in pulmonary recurrence, and 48% vs 22% in local recurrence (all P < .001).
Conclusion: It is useful to take these characteristics of recurrence into account in the management of patients after curative resection for colorectal cancer and in the setting of clinical trial for follow-up after curative resection for colorectal cancer.