Different variables predict the outcome of patients with synchronous versus metachronous metastases of colorectal cancer

Abstract

Purpose: Timing of metastasis is a controversial prognostic factor for patients with metastatic colorectal cancer (mCRC), as well as the performance of the common prognostic variables within patients with synchronous (SMs) or metachronous metastases (MMs). The aim of the current study is to evaluate outcome by the timing of metastases and to explore different tumor characteristics associated with SMs and MMs.

Methods: Data were collected from the clinical records of patients with mCRC, which were referred to the Department of Oncology of the Ospedale Civile di Sanremo from 2006 to 2011. A comparison of the characteristics of tumors of patients, overall and by the timing of metastases, and a Cox regression analysis have been performed to select the most relevant prognostic factors. Finally, the characteristics of the variables associated with the outcome were analyzed through a logistic regression.

Results: Two hundreds fifteen patients with SMs and two hundreds ten with MMs were included. Patients with SMs reported a poor prognosis (18.5 versus 62.8 months; p value < 0.001). Among patients with SMs there was a significant difference in overall survival between patients with a CEA-positive or negative disease, while no difference was present among patients with MMs. After multivariate analysis, only within the SMs group the occurrence of liver metastases was related to a CEA-positive disease.

Conclusions: Within the cohort of SMs high CEA levels, occurrence of liver metastases and right-sided colon tumors were associated with a very poor prognosis, whereas no relationship was detectable in the group of patients with MMs.

Keywords: Carcinoembryonic antigen; Colorectal cancer; Overall survival; Right-sided colon cancer; Synchronous metastases.