Evaluation of P-POSSUM and CR-POSSUM scores in patients with colorectal cancer undergoing resection

Introduction: The aim of this study was to evaluate the predictive accuracy of P-POSSUM and CR-POSSUM models on patients undergoing colorectal resection. Methods: P-POSSUM and CR-POSSUM predictor equations for mortality were applied retrospectively to 321 patients who had undergone colorectal resection for cancer. P-POSSUM and CR-POSSUM scores were validated by assessing their calibration and discrimination. Calibration was assessed using the Hosmer-Lemeshow goodness-of-fit test and the corresponding calibration curves. Evaluation of the discriminative capability of both models was performed using receiver-operating characteristic (ROC) curve analysis. Results: Overall, 22 deaths were observed. CR-POSSUM predicted 25 deaths (chi(2) = 12.20, P = 0.13), and P-POSSUM predicted 29 deaths (chi(2) = 18.85, P = 0.002). ROC curves analysis revealed that CR-POSSUM has reasonable discriminatory power for mortality. Conclusions: These data suggest that CR-POSSUM may provide a better estimate of the risk of mortality for patients who undergoing colorectal resection.