Why recurrence was initially suspected during colorectal cancer postoperative surveillance? A retrospective analysis

Routine postoperative surveillance is recommended for the patients with colorectal cancer (CRC). This study aimed to clarify the conditions indicate initial suspicion of CRC recurrence in different preoperative serum carcinoembryonic antigen (CEA) level groups, including positive physical signs/symptoms, elevated CEA level, positive radiologic studies results, and other elevated tumor markers.A total of 2268 patients with recurrence after curative surgery for CRC were enrolled in this study. The patients were classified into 3 groups according to preoperative serum CEA level (low, <2 ng/mL; intermediate, ≥2 and <5 ng/mL; and high, ≥5 ng/mL).Up to 63.6% of recurrence was suspected based on elevated CEA level in the high preoperative serum CEA level group. Patients in the low preoperative serum CEA level group had a higher rate of initial suspicion of recurrence based on positive physical signs or symptoms (36.7% vs 26.9% vs 20.4%, P <.001) and positive radiologic findings (51.4% vs 40.7% vs 29.5%, P < .001) than those in the intermediate and high preoperative serum CEA groups.Conditions indicate initial suspicion of recurrence varied in the different preoperative serum CEA level groups. In patients with low preoperative serum CEA level, the detection of recurrence depend on abnormal CEA level is less sensitive than intermediate and high preoperative serum CEA groups. We suggest that the strategy for CRC surveillance should not depend on serum CEA level alone. The signs or symptoms of patients, changes in postoperative serial CEA level, and ongoing radiologic or imaging findings must be cautiously monitored.