Clinical characteristics and prognostic analysis of circulating tumor cells in peripheral blood and surgical lavage fluid from patients with colorectal cancer.

This study aimed to characterize the distribution of circulating tumor cells (CTCs) in preoperative peripheral blood and intraoperative surgical lavage fluid from patients with colorectal cancer (CRC), and to evaluate the association between CTC levels and clinical prognosis to determine their potential as novel prognostic biomarkers. Preoperative peripheral blood (7.5 ml) was collected from 185 CRC patients and from 50 healthy controls. During laparoscopic surgery, 150 ml of surgical lavage fluid was obtained from each patient at three key time points: before tumor resection, after tumor resection and after mesenteric incision of the tumor. CTCs were detected using the CanPatrolTM enrichment system combined with RNA in situ hybridization. Associations between CTC counts and clinical indicators were analyzed, and their relationship with progression-free survival (PFS) and overall survival (OS) was evaluated. The CTC-positive rate in both peripheral blood and surgical lavage fluid was associated with tumor invasion depth, TNM stage and metastasis. TNM stage and CTC counts in peripheral blood and lavage fluid were identified as independent predictors of mortality. Among patients with CTC-positive lavage fluid after tumor mesangial dissection, both PFS and OS were significantly shorter compared with CTC-negative patients (PPFS=0.0015, POS=0.0013). These findings indicate that CTC counts in peripheral blood and surgical lavage fluid serve as important biomarkers for predicting CRC prognosis and are closely associated with both PFS and OS.