84P - Comprehensive evaluation of relapse risk (CERR) score for colorectal liver metastases development and validation

Background

To modify the tumor burden score (TBS) and to develop a comprehensive and practical prognostic scoring system among Chinese patients with colorectal liver metastases (CRLM).

Methods

787 adult patients who underwent curative-intent liver resection for CRLM were identified from Zhongshan Hospital in Shanghai, China between June 2010 and January 2018. Tumor relapse-free survival (RFS) was the main outcomes. TBS was modified with geometric algorithms. The Cox regression model was used to identify independent predictors of prognosis. Time-dependent AUC, calibration curve, and C-index were employed to validate the predictive ability of a survival model.

Results

Modified TBS (mTBS) was established by a mathematical equation (parameters were CRLM size, CRLM number, and unilobar/bilobar metastasis). mTBS model (AUC=0.62 at 33 Month) out-performed TBS model (AUC=0.54 at 33 Month) in predicting RFS (P=.002). Five preoperative predictors of worse RFS were identified and were incorporated into CERR score: KRAS/NRAS/BRAF mutated tumor (score 1 point); node-positive primary (1 point); extrahepatic disease (1 point); CEA level >200 ng/ml or CA 19-9 >200 U/mL (1 point); mTBS between 5 and 11 (1 point) or 12 and over (2 points). Patients undergoing hepatectomy for CRLM were stratified by CERR score into risk groups: high-risk group (CERR score 4 or more) had a 3-year RFS rate of 9.77%; medium-risk group (CERR score 2-3) had a 3-year RFS rate of 21.96%; low-risk group (CERR score 0-1) had a 3-year RFS rate of 39.90%. The CERR score model was further validated using internal bootstrap validation, and the discriminatory capacity of the CERR score was significantly superior to that of the Fong score and that of the Genetic and Morphological Evaluation (GAME) score.

Conclusions

Modified TBS should be promoted. The CERR score is a powerful prognostic tool that can help to determine the optimal clinical management strategies.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Zhongshan Hospital.

Funding

The National Natural Science Foundation of China.

Disclosure

All authors have declared no conflicts of interest.