Univariate analysis indicates that age, high CEA level, WHO performance status ≥2, B-Raf mutated tumor status, synchronous metastatic disease, absence of complete surgery of metastases, localization of primary tumor in colon, absence of anti-EGFR therapy, and more than 1 metastatic site were significantly associated with poorer OS (Table 2). This evidence concerns the gene CEACAM5 and metastatic neoplasm.