Impact of preoperative inflammatory and nutritional markers on the prognosis of patients with peritoneal metastasis of colorectal cancer.

Background: Identifying patients with peritoneal metastasis (PMs) of colorectal cancer (CRC) who will benefit from cytoreductive surgery and hyperthermic intraperitoneal chemotherapy is crucial before surgery. Inflammatory and nutritional indicators play essential roles in cancer development and metastasis.

Aim: To investigate the association of preoperative inflammatory and nutritional markers with prognosis in patients with CRC-PM.

Methods: We included 133 patients diagnosed with CRC-PM between July 2012 and July 2018. Patients' demographics, overall survival (OS), and preoperative inflammatory and nutritional markers were evaluated. The Kaplan-Meier method and log-rank test were used to estimate differences.

Results: Of the 133 patients, 94 (70.6%) had normal hemoglobin (Hb) and 54 (40.6%) had a high neutrophil-to-lymphocyte ratio (NLR). The median OS (mOS) was significantly lower for patients with high NLR (7.9 months) than for those with low NLR (25.4 months; P = 0.002). Similarly, patients with normal Hb had a longer mOS (18.5 months) than those with low Hb (6.3 months; P < 0.001). Multivariate analysis identified age, carbohydrate antigen 199 levels, NLR, Hb, and peritoneal cancer index as independent predictors of OS. Based on these findings, a nomogram was constructed, which demonstrated a good capacity for prediction, with a C-index of 0.715 (95% confidence interval: 0.684-0.740). Furthermore, the 1- and 2-year survival calibration plots showed good agreement between predicted and actual OS rates. The areas under the curve for the 1- and 2-year survival predictions of the nomogram were 0.6238 and 0.6234, respectively.

Conclusion: High NLR and low Hb were identified as independent predictive risk factors for poor prognosis in patients with CRC-PM. The established nomogram demonstrated high accuracy in predicting OS for patients with CRC-PM, indicating its potential as a valuable prognostic tool for this patient population.