The analysis included 20 patients (12 females; 8 males) with unresectable liver metastases in the course of CRC with KRAS, NRAS and BRAF mutations, who underwent 73 chemoembolization procedures with microspheres loaded with 100 mg of irinotecan, in combination with interspersed FOLFIRI chemotherapy. The gene discussed is NRAS; the disease is colorectal carcinoma.