Perioperative Serum Albumin and White Blood Cell Count for Early Postoperative Risk Stratification of Superficial Surgical Site Infection After Colorectal Cancer Surgery

Background: Surgical site infection (SSI) is a common complication after colorectal cancer (CRC) surgery. We evaluated routinely available perioperative biomarkers for early prediction of superficial SSI after curative CRC surgery. Methods: This retrospective study included 488 patients undergoing elective curative CRC resection. Preoperative and postoperative day (POD) 1 laboratory parameters were evaluated using receiver operating characteristic curve analysis and multivariable logistic regression. Results: Superficial SSI developed in 66 patients (13.5%). In the perioperative multivariable association model, preoperative serum albumin ≤ 3.70 g/dL (odds ratio [OR], 1.918; 95% confidence interval [CI], 1.066–3.449; p = 0.030) and WBC count ≥ 6.30 × 103/µL (OR, 1.970; 95% CI, 1.123–3.458; p = 0.018) were independently associated with superficial SSI. On POD1, serum albumin ≤ 2.80 g/dL (OR, 3.447; 95% CI, 1.993–5.963; p < 0.001) and WBC count ≥ 10.50 × 103/µL (OR, 2.822; 95% CI, 1.600–4.976; p < 0.001) remained independently associated with SSI. Although lower POD1 lymphocyte-to-monocyte ratio was associated with SSI in univariable analysis, it was not significant after adjustment. A combined model incorporating dichotomized preoperative and POD1 albumin and WBC counts showed modest discrimination (AUC, 0.731; 95% CI, 0.663–0.800), with 47.0% sensitivity and 89.3% specificity. Conclusions: Perioperative albumin and WBC counts were independently associated with superficial SSI. POD1 assessment may aid early risk stratification; however, the modest performance indicates that these biomarkers should complement rather than replace clinical surveillance. Prospective external validation is required.