The clinical impact of intraoperative bleeding on peritoneal recurrence after surgery for stage II to III colorectal cancer.

Background: This study aimed to investigate the risk factors for peritoneal recurrence (PR) in patients with stage II to III colorectal cancer who underwent colorectal surgery.

Methods: A retrospective study was conducted on 232 patients who underwent colorectal surgery for stage II to III colorectal cancer. Univariate and multivariate analyses were performed to determine risk factors for PR.

Results: The overall incidence of PR was 8.2 % (19/232). A univariate Cox regression analysis showed that a higher level of carcinoembryonic antigen (CEA) (P = 0.039), higher levels of carbohydrate antigen 19-9 (CA19-9) (P < 0.001), preoperative bowel obstruction (P = 0.011), tumor invasion of T4 category (P = 0.019), lymph node metastasis (P = 0.016), poorly differentiated, mucinous or signet-ring histological type (P = 0.010), larger amount of intraoperative bleeding (P = 0.002), R1 resection (P = 0.003), anastomotic leakage Clavien-Dindo classification (CD) ≥2 (P = 0.018), longer postoperative stay (P = 0.002), and recurrence of other organs preceding disseminated recurrence (P = 0.004) were observed significantly more frequently in patients with PR than in patients without PR. A multivariate Cox regression analysis revealed that poorly differentiated, mucinous, or signet-ring histological type (HR: 5.067, 95 % CI: 1.192-21.534, P = 0.028) and intraoperative bleeding (HR: 1.003, 95 % CI: 1.000-1.005, P = 0.017) were independent risk factors for PR. Peritoneal recurrence-free survival curves generated using the Kaplan-Meier method gradually worsened with increasing intraoperative bleeding (P < 0.001). In addition, the sub-analyses between stage II and stage III and between ≤ cT3 and cT4 also demonstrated that peritoneal recurrence-free survival worsened with increasing intraoperative bleeding.

Conclusions: Our findings suggest that histological type, and intraoperative bleeding are risk factors for PR in patients who undergo colorectal surgery for stage II to III colorectal cancer. In particular, peritoneal recurrence is associated with increased intraoperative bleeding.