RESUMEN
Transarterial radioembolization using yttrium-90 (90Y) therapy has become a standard modality of treatment for primary and metastatic liver malignancies due to its high efficacy rate and relatively low risk of adverse effects compared to other forms of locoregional and systemic therapies. Non-target distribution of radio embolic beads and adjacent structure radiation are the two most common adverse effects. However, these are rarely encountered due to thorough imaging and mapping studies prior to 90Y therapy. We present the case of a 66-year-old male who developed a radiation-induced gastric ulcer following 90Y therapy with negative pre-procedural imaging and mapping who was retrospectively found to have an accessory artery from the left hepatic artery to the gastric antrum.