Elevated serum IL-17 levels and intraoperative hypothermia are risk factors for early postoperative anastomotic leakage in rectal cancer: a prospective observational study.

Objective: In this prospective observational cohort study, we aim to investigate the risk factors for early postoperative anastomotic leakage (AL) in patients undergoing rectal cancer resection.

Methods: This study included 459 patients with rectal cancer who underwent treatment at our hospital from January 2021 to October 2022. All patients were hospitalized for 1 week postoperatively and observed for the occurrence of AL. Fasting venous blood samples (5 mL) were collected from all cases 1 day before surgery and 1, 2, and 3 days after surgery, and serum levels of interleukins (IL)-17, IL-6, IL-1β, tumor necrosis factor-α, and C-reactive protein (CRP) were determined using enzyme-linked immunosorbent assay. Demographic, clinical data, intraoperative hypothermia, and nutritional indicators were collected for all patients. Statistical analysis was performed using SPSS 25.0 software.

Results: AL patients had significantly lower hemoglobin, albumin (ALB) levels, and a higher proportion of intraoperative hypothermia compared to patients in the non-AL group (P < .05). On the first, second, and third days after surgery, patients in the AL group had significantly higher levels of serum CRP, IL-1β, and IL-17 compared to the non-AL group. Pearson's correlation analysis showed a positive correlation between serum IL-17 levels and CRP levels. Serum IL-17 had the highest predictive value for early AL, with an area under the curve (AUC) of 0.755 cutoff value of 94.77 pg/mL, a sensitivity of 70.1%, and a specificity of 66.0%. Moreover, logistic regression analysis indicated that intraoperative hypothermia, decreased ALB levels, and increased CRP, IL-1β, and IL-17 levels on the first day after surgery were identified as risk factors for early AL in rectal cancer patients.

Conclusions: This study found a significant elevation of IL-17 levels in the serum of patients who experienced early postoperative AL. Furthermore, intraoperative hypothermia and elevated IL-17 levels on the first day after surgery were identified as risk factors for early postoperative AL in rectal cancer patients.