Colorectal cancer (CRC) is the third most common malignancy worldwide, with approximately 70% of patients diagnosed at an advanced stage [1,2]. Although surgical resection remains the primary curative treatment for CRC, approximately 30–50% of patients experience postoperative recurrence or metastasis [3]. Current international guidelines (including ASCO, ESMO, and NCCN) recommend rigorous postoperative surveillance to facilitate early detection of recurrent lesions, thereby providing opportunit…