The Combination of Prognostic Nutritional Indicator and Serum Carcinoembryonic Antigen is Useful in Predicting Postoperative Recurrence in Stage II Colorectal Cancer

[Background] The efficacy of adjuvant chemotherapy in stage II colorectal cancer (CRC) patients has not been clearly demonstrated. Therefore, identification of robust prognostic factors is crucial for the assessment of recurrence risk in stage II CRC and appropriate adjuvant treatment, in clinical practice. [Methods] We enrolled 135 colorectal adenocarcinoma patients who underwent proctocolectomies and had histologically diagnosed stage II CRC. [Results] Receiver operating characteristic (ROC) analysis, to evaluate the predictive ability of certain serum factors for CRC recurrence, indicated that the prognostic nutritional indicator (PNI), followed by serum carcinoembryonic antigen (CEA) level, were the strongest predictive metrics. Based on cutoff values from ROC analyses, patients were divided as follows; CEAHigh (≥ 4.55 ng/mL), CEALow (< 4.55 ng/mL), PNIHigh (≥ 47.72), and PNILow (< 47.72). The recurrence rates of patients with CEAHigh and PNILow, CEAHigh and PNIHigh, CEALow and PNILow, and CEALow and PNIHigh were 34.3%, 0%, 6.8%, and 2.6%, respectively (a significant difference at P < 0.0001). Logistic regression analysis revealed that the combination of serum CEA level and PNI was an independent predictive indicator of tumor recurrence after operation in stage II CRC patients. The 5-year disease specific survival rates of patients with CEALowPNIHigh, CEAHighPNIHigh, CEALowPNILow, CEAHighPNILow were 100%, 100%, 97.4%, and 77.5%, respectively (P < 0.0001). [Conclusion] The combination of CEA and PNI was useful in predicting postoperative recurrence in stage II CRC patients.