Nomograms incorporating preoperative RDW level for the prediction of postoperative complications and survival in colorectal liver metastases after resection.

BACKGROUND

This study aimed to investigate the predictive significance of preoperative red cell volume distribution width (RDW) level for prognosis and to establish nomograms incorporating preoperative blood markers to predict postoperative complications and survival in patients with colorectal liver metastases (CRLM).

METHODS

This retrospective study included 380 enrolled CRLM patients who underwent hepatic resection. Predictors of postoperative complications were explored using binary logistic regression analysis. Covariates associated with overall survival (OS) and progression-free survival (PFS) were evaluated through univariate and multivariate Cox regression analyses. Only variables that reached statistical significance at P<0.1 in the univariate analysis were allowed to enter the multivariate analyses. The independent predictors that retained in the final multivariate model were incorporated into nomograms.

RESULTS

The optimal cut-off point of preoperative RDW-CV was 16%, and elevated RDW-CV was significantly associated with better prognosis (mPFS: 5.0 vs. 8.9 months, P=0.007; mOS: 59.0 vs. 42.0 months, P=0.041). The optimal cut-off point of preoperative RDW-SD was 43.9 fl, and elevated RDW-SD was significantly associated with worse prognosis (mPFS: 8.0 vs. 13.0 months, P<0.001; mOS:36.8 vs. 70.2 months, P=0.001). A nomogram predicting postoperative complications was constructed based on preoperative gamma-glutamyl transpeptidase (GGT) ≥34.5 U/L, preoperative RDW-CV ≥14.1%, and intraoperative blood loss ≥200.0 mL, with AUROC of 0.658. The calibration curves and Hosmer-Lemeshow test revealed desirable model calibration (chi-square: 3.99, P=0.91). A nomogram predicting PFS was constructed based on preoperative GGT ≥31.0 U/L, preoperative D-dimer ≥0.251 mg/L, preoperative RDW-CV <16.0%, preoperative RDW-SD ≥43.9 fl, positive lymph node metastasis, bilobar liver distribution, and R0 resection with good discrimination (C-index: 0.676±0.016) and calibration. A nomogram for the prediction of OS was constructed with favorable discrimination (C-index: 0.700±0.021) and calibration. Significant differences in PFS and OS were shown among patients stratified into three different risk groups (P<0.001) based on the nomograms.

CONCLUSIONS

This study first revealed the relationship between preoperative RDW-SD, RDW-CV, and prognosis in patients with CRLM. It also established nomograms especially considering preoperative blood markers to predict postoperative complications, PFS, and OS, which facilitated physicians to determine the optimal clinical management strategies.