e20137 Background: We aim to explore the efficacy and tolerability of Drug-Eluting Bead Bronchial Arterial Chemotherapy Embolization (DEB-BACE) combined with intravenous chemotherapy in the treatment of patients with initially diagnosed extensive-stage small cell lung cancer (SCLC). Methods: We collected data from 24 patients with extensive-stage small cell lung cancer who received DEB-BACE combined with intravenous chemotherapy (DEB-BACE-V) and initially diagnosed at our hospital between 2013 and 2022. Among them, nine patients received BACE combined with intravenous chemotherapy from the first-line (first-line DEB-BACE-V), ten patients from the third-line (third -line DEB-BACE-V), and five patients from the second-line (second -line DEB-BACE-V). Then, the treatment response (objective response rate and rate of cancer regression) and tumor marker levels were evaluated at the first month and third month after treatment. The quality of life was assessed using the EORTC QLQ-C30 scale. Overall survival (OS) was also evaluated. First, compare the first-line DEB-BACE-V group with the second-line DEB-BACE-V group. Then, compare the first-line DEB-BACE-V group with third-line DEB-BACE-V group. Lastly, compare the second-line DEB-BACE-V group with the third-line DEB-BACE-V group. Results: In initially diagnosed extensive-stage SCLC patients treated with DEB-BACE combined with intravenous chemotherapy, first and third month post treatment, the objective response rates were 58.33% and 79.17%, respectively; and the rates of cancer regression were 75% and 91.67%, respectively. In addition, the neuron-specific enolase (NSE) and progastrin-releasing peptide levels were reduced at the third and sixth month. Quality of life assessed by EORTC QLQ-C30 scale, which included subscales of general health status, functional domains, symptom domains, and single domains except for financial difficulty, was markedly improved in first and third month of post treatment. Adverse reactions were mild and manageable, the most common being chest pain and low fever. Median values of OS in first-line DEB-BACE-V, second -line DEB-BACE-V and third -line DEB-BACE-V were 15.7 (95% CI: 9.1595-20.759) months, 29.63 (95% CI: 20.5684-36.268) months 16.92 (95% CI: 10.4044-21.871) months, and respectively. Conclusions: Due to its favorable therapeutic response, quality of life, survival benefits, and safety profile, DEB-BACE combined with intravenous chemotherapy may become a treatment option for patients with extensive-stage SCLC, particularly as second-line therapy.