Background: Prognostic and predictive factors are becoming more important in mCRC patients, and may have an impact in overall survival and in the number of lines of chemotherapy that a patient can receive. Methods: We conducted a retrospective analysis of 334 patients with mCRC. We analyzed the clinical characteristics of 113 (33.8%) mCRC patients who received ≥3 lines of chemotherapy. We apply the statistical test Chi square in order to identify significant association. Results: Several characteristics were significantly associated with receiving ≥ 3 lines of chemotherapy (n = 113): age < 80 years (n = 93, OR = 3.07, p = 0.001), ECOG 0-1 (n = 98, OR = 3.21, p = 0.055), primary tumor resection (n = 62, OR = 2.36, p = 0.000) and resection of metastases (n = 56, OR = 2.07, p = 0.002). Partial or complete response rate in the first line of chemotherapy was also significantly associated with receiving ≥ 3 lines of treatment (n = 65, p = 0.011). Tumor mutational status was analyzed in 333 patients: KRAS mutation was detected in 163 over 333 patients genotyped (48.9%), NRAS in 25/206 (12.1%), BRAF in 15/217 (6.9%) and PI3K in 31/213 (14.5%). In the group of patients receiving ≥ 3 lines of chemotherapy (n = 113): KRAS mutation was found in 60/113 patients (53.1%), NRAS in 5/77 (6.5 %), BRAF in 5/84 (5.9%) and PI3K in 8/80 (11.1%). Tumor mutations were not significantly associated with ≥ 3 lines of chemotherapy. No significant association was found between sex, tumor location (right [n = 33, 29.2%] or left [n = 76, 73%]), liver or lung isolated metastases and 3 or later lines of chemotherapy. We also performed in our database a survival analysis in the 334 patients: those who received ≥3 lines of chemotherapy had significantly higher survival rates (median OS 18 m in the group of < 3 lines of treatment vs. 37.2 m in the group of ≥ 3 lines of chemotherapy, HR = 1,6; CI 95% 1,2-2.1; p < 0,001). Conclusions: This retrospective analysis showed that mCRC patients with < 80 years, ECOG 0-1, primary tumor and or metastases resected and those with complete or partial response in the first line of treatment have a higher probability of receiving ≥ 3 lines of chemotherapy.