Maximum Diameter and Number of Tumors as a New Prognostic Indicator of Colorectal Liver Metastases

Abstract

Background: Surgical resection is currently considered the only potentially curative option as a treatment strategy of colorectal liver metastases (CRLM). However, the criteria for selection of resectable CRLM are not clear. The aim of this study was to confirm a new prognostic indicator of CRLM after hepatic resection.

Patients and methods: One hundred thirty nine patients who underwent initial surgical resection from 1994 to 2015 were investigated retrospectively. Prognostic factors of overall survival including the product of maximum diameter and number of metastases (MDN) were analyzed.

Results: Primary tumor differentiation, vessel invasion, lymph node (LN) metastasis, non-optimally resectable metastases, H score, grade of liver metastases, resection with non-curative intent and MDN were found to be prognostic factors of overall survival (OS). In multivariate analyses of clinicopathological features associated with OS, MDN and non-curative intent were independent prognostic factors. Patients with MDN ≥30 had shown significantly poorer prognosis than patients with MDN <30 in OS and relapse-free survival (RFS).

Conclusion: MDN ≥30 is an independent prognostic factor of survival in patients with CRLM and optimal surgical criterion of hepatectomy for CRLM.

Keywords: Colorectal liver metastases; MDN; prognostic factor.

Figure 1. Overall and relapse-free survival curves of 139 patients with colorectal liver metastases who underwent initial surgical resection.

Figure 2. Kaplan–Meier curves for (a) overall survival and (b) relapsefree survival in patients with colorectal liver metastases (CRLM) of MDN ≥30 and <30.