Emergency surgery for complicated colon cancer is associated with high morbidity and mortality, and selecting between primary anastomosis and stoma formation remains challenging. Systemic inflammation may influence intraoperative decisions and postoperative outcomes, but its role in emergency settings is not fully established. This retrospective study included patients undergoing emergency surgery for complicated colon cancer between October 2020 and January 2025. Patients were grouped according to surgical strategy (primary anastomosis vs. stoma formation). Preoperative inflammatory biomarkers—C-reactive protein (CRP), neutrophil-to-lymphocyte ratio (NLR), and systemic immune-inflammation index (SII)—were analyzed in relation to surgical decisions, postoperative complications, anastomotic leakage, and 30-day mortality using multivariate logistic regression and ROC curve analyses. Among 221 patients, 136 (61.5%) underwent primary anastomosis and 85 (38.5%) stoma formation. Higher CRP, NLR, and blood glucose levels were independently associated with a lower likelihood of primary anastomosis (AUC = 0.764). Postoperative complications occurred in 40.7% of patients and were independently predicted by body mass index, Charlson Comorbidity Index, serum creatinine, blood glucose, and NLR (AUC = 0.851). Anastomotic leakage was strongly associated with elevated CRP, NLR, SII, and serum creatinine, with CRP showing the highest predictive accuracy (AUC = 0.894). Elevated NLR and serum creatinine independently predicted 30-day mortality. Preoperative inflammatory biomarkers, particularly CRP and NLR, offer important prognostic value for surgical decision-making and early postoperative outcomes in emergency colon cancer surgery.