EP.TH.37Radioembolization with yttrium-90 microspheres for management of breast liver metastases: a systematic review and pooled analysis

Aims Radioembolization with yttrium-90 microspheres is an emerging option for management of liver metastases of breast cancer when other systemic therapies have failed. The aims of this systematic review were to assess the effect of radioembolization on i) tumour response and ii) patient survival post -radioembolization. Methods The review was performed using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). A systematic literature search was performed using the PubMed and EMBASE databases from January 2007 to December 2019. The initial search yielded 265 reports which were potentially suitable for inclusion in this review. Studies published in English reporting at least one outcome of interest were considered to be suitable for inclusion. Conference abstracts; case reports, animal studies and reports not published in English were excluded from this review. Results The final number of studies which met the inclusion criteria was 12 (n = 452 patients). There were no randomized controlled trials identified. The age of the patients included in this review ranged from 52 to 61 years. The duration of follow-up ranged from 6 to 15.7 months. The total number of patients with breast metastases not confined to the liver was 236 (52.2%). Cumulative analysis revealed that radioembolization conferred tumour control rate in 81% of patients. Overall survival post-radioembolization ranged from 3.6 to 20.9 months with an estimated mean survival of 11.3 months. Conclusion Radioembolization with ytrrium-90 appears to confer control of tumour growth rate in most patients, however its effect on patient survival need to be elucidated further.