BACKGROUND In recent years survival of patients with metastatic colorectal cancer (mCRC), though still limited, has improved significantly; clearly, when the disease becomes refractory to standard regimens, additional treatment options are needed. Studies have shown that mitomycin C (MMC), an antitumor antibiotic, and capecitabine, a precursor of 5-fluorouracil, may act synergistically in combination. The efficacy of MMC/capecitabine has been demonstrated in the first-line setting, but only a few small studies have tested it in the advanced-line setting, with contradictory results. AIM To summarize our experience using MMC/capecitabine as an advanced line treatment for mCRC. METHODS A retrospective study was conducted at a tertiary medical center including all patients with histologically proven mCRC who were treated with MMC/capecitabine after at least two previous lines of standard chemotherapy in 2006-2020. Data on patient demographics and past medical history, laboratory, pathological, and radiological factors, and treatment and survival were collected from the files. Survival analyses were performed using the Kaplan-Meier method. The association of patient and tumor characteristics with treatment effectiveness and toxicity was evaluated with univariate and multivariate proportional hazard Cox regression analyses. P ≤ 0.05 was considered statistically significant. RESULTS The cohort consisted of 119 patients of median age 64 years (range 37-85). Patients received a median of 2 MMC/capecitabine cycles (range 0.5-9.0). Thirty-four patients (28.6%) experienced grade ≥ 3 toxicity, including 2 (1.7%) with grade 4; there was no drug-related mortality. The objective response rate was 0.8%, and the disease control rate, 24.4%. Median progression-free survival (PFS) was 2.1 mo (range 0.2-20.3), and median overall survival, 4.8 mo (range 0.2-27.5). The 6-month overall survival rate was 44%; 8.7% of patients remained progression-free. Factors associated with longer PFS were lower gamma-glutamyl transferase level (P = 0.030) and primary tumor location in the left colon (P = 0.017). Factors associated with longer overall survival were lower gamma-glutamyl transferase level (P = 0.022), left-colon tumor location (P = 0.044), low-to-moderate histological grade (P = 0.012), Eastern Cooperative Oncology Group performance status 0-1 (P = 0.036), and normal bilirubin level (P = 0.047). CONCLUSION MMC/capecitabine is an active, available, and relatively safe regimen for use beyond standard lines of therapy in mCRC. Several clinical and laboratory parameters can identify patients more likely to benefit.