Abstract:  Objective To observe the efficacy and safety of Callispheres drug-eluting bead transarterial chemoembolization (DEB-TACE) on the unresectable colorectal cancer liver metastases with systemic chemotherapy failure. Methods The clinical data of 42 patients with unresectable colorectal cancer liver metastasis who failed at least second-line systemic chemotherapy and admitted to Linyi Cancer Hospital of Shandong province from June 2018 to June 2020 were retrospectively analyzed. All patients received TACE with 100-300 μm Callispheres microspheres loaded with irinotecan. The tumor response was evaluated after DEB-TACE, the overall survival (OS), progression-free survival (PFS), adverse reactions during treatment and the factors affecting the OS were analyzed. Results At 2, 4 and 6 months after DEB-TACE, the objective response rate (ORR) were 83.3%, 81.0% and 71.4%, respectively; the disease control rate (DCR) were 100.0%, 90.5% and 80.9%, respectively; the median PFS was 11.0 months and the median OS was 16.0 months. The main adverse reactions were fever, pain, nausea and vomiting, which occurred mainly in grade 1-2 patients, and no serious complications such as ectopic embolism occurred. Multivariable Cox regression analysis showed that simultaneous liver metastasis (HR=0.446, 95%CI: 0.279-0.780, P=0.002)  and extrahepatic metastasis  (HR=0.311, 95%CI:0.134-0.968, P=0.007) were independent risk factors affecting OS. Conclusions DEB-TACE has certain clinical efficacy and manageable adverse reactions in the treatment of patients in unresectable colorectal cancer liver metastases with systemic chemotherapy failure, while the prognosis of patients with simultaneous liver metastasis or extrahepatic metastasis is poor.

Key words:  Colorectal neoplasms, Transarterial chemoembolization, Drug-eluting bead, Liver metastases, Systemic chemotherapy