Upgraded nomograms for the prediction of complications and survival in patients with colorectal liver metastases treated with neoadjuvant chemotherapy followed by hepatic resection

BACKGROUND: To establish upgraded nomograms incorporating neoadjuvant chemotherapy (NAC)-related factors and preoperative testing markers to predict postoperative complications, progression-free survival (PFS) and overall survival (OS) in patients with colorectal liver metastases (CRLM). METHODS: Multivariate regression analyses were used to reveal independent predictors for postoperative complications, PFS and OS. Nomograms incorporating independent predictors were constructed, and discrimination and calibration were evaluated. Survival was estimated by the Kaplan-Meier method and compared using the log-rank test. RESULTS: A nomogram predicting postoperative complications was constructed based on preoperative serum gamma-glutamyl transpeptidase (GGT) ≥36 U/L, major liver resection, intraoperative blood loss ≥300 mL, primary site located in the right hemicolon and primary lymph node metastasis, with an area under the receiver operating characteristic curve (AUROC) of 0.750. The calibration curves and Hosmer-Lemeshow test revealed desirable model calibration (chi-square: 4.47, P=0.88). Moreover, a nomogram for the prediction of PFS was constructed based on tumour regression grade (TRG), primary lymph node metastasis, R0 resection and NAC cycles ≥5, with good discrimination (C-index: 0.663±0.024) and calibration, and one for predicting OS was constructed based on preoperative GGT ≥36 U/L, NAC toxicity, NAC cycles ≥5, primary lymph node metastasis and R0 resection, with favourable discrimination (C-index: 0.684±0.030) and calibration. Significant differences in PFS and OS were observed among patients stratified into three different risk groups (P<0.001) according to total scores based on the nomograms. CONCLUSIONS: This study is the first to establish novel predictive nomograms specifically incorporating TRG, NAC toxicity and serum GGT level for the prediction of postoperative complications, PFS and OS in CRLM patients. The nomograms exhibit favourable discrimination and calibration to guide personalized CRLM management and therapy.