According to the results from the univariate analysis for clinical factors, PFS was significantly shorter in patients with liver metastases (hazard ratio [HR]: 3.27; 95% CI: 1.59–6.69, P = 0.001) and patients with two or more metastatic sites (HR: 1.99; 95% CI: 1.04–3.78, P = 0.036), while there was no significant improvement of PFS in patients with a KRAS mutant tumor (HR: 0.53; 95% CI: 0.27–1.03, P = 0.062). Here, KRAS is linked to neoplasm.