The smallest colorectal liver metastasis size as a prognosis factor after laparoscopic liver resection

Abstract

Liver resection is a curative treatment for patients with colorectal liver metastasis (CRLM). However, about 70% patients will experience recurrence after resection. CRLM number and maximum (CRLMmax) size have been associated with recurrence after hepatic resection. Still, association between CRLM minimum (CRLMmin) size and tumor recurrence has never been evaluated. This study aimed to correlate CRLMmin on the liver specimen with recurrence free survival (RFS). We retrospectively included all patients who underwent first laparoscopic liver resection for CRLM from January 2000 to November 2018 in a single institution. Patients with extra hepatic evolutive disease were excluded. A CRLMmin cut off was selected using the time-dependent area under the curve (td-AUC) for 1 and 2-year RFS. Cox uni and multivariate models were constructed. Multivariate analysis was completed for factors with a p value ≤ 0.10 upon univariate analysis, or previously known determinant factors. Primary end point was RFS. Overall, 227 patients were included. Median follow- up was 50 months (6-210), 151 (67%) patients presented with recurrence. The optimal CRLMmin cutoff associated with RFS was 9mm (12 and 24-months td-AUC = 0.56 and 0.52, respectively). Median RFS were respectively 11.9 months (CI 95% 7.1-18.7) in patients with CRLMmin size <9mm and 21.9 months (CI 95% 18.5-30.8) for those with CRLMmin size ≥9mm (p < 0.001). In multivariate analysis, CRLMmin size <9mm was an independent prognostic factor for RFS after adjusting on node-positive primary tumor, preoperative carcinoembryonic antigen ACE ≥5ng/ml, multiple liver metastasis and synchronous or metachronous <12months liver metastasis (HR = 1.6 (1.1-2.4); p < 0.05). Also, CRLMmin size <9mm was independently associated with hepatic RFS (HR = 1.8 (1.2-3,0); p < 0.05) but not extra-hepatic RFS. The present study suggests that CRLMmin size <9mm on the liver specimen was an independent progonostic factor for worse RFS, particularly associated with poor local control over distant metastasis control. David Fuks. Has not received any funding. All authors have declared no conflicts of interest.