Clinical impact of Yttrium-90 resin microsphere radioembolization-induced hepatic adverse events and associations with predictive dosimetry.

[OBJECTIVE] Radioembolization-induced liver disease (REILD) is a potentially life-threatening complication that can develop after yttrium-90 (Y-90) radioembolization. Our study determined to find associations between liver toxicity and Y-90 dosimetry.

[METHODS] We analyzed cases of REILD and isolated hyperbilirubinemia that developed after Y-90 resin microsphere radioembolization for hepatocellular carcinoma with a focus on dosimetric parameters.

[RESULTS] Out of a cohort of 413 patients, 12 patients developed REILD, and 17 patients had grade 3 isolated hyperbilirubinemia. All patients in the REILD group were Barcelona-Clinic Liver Cancer (BCLC) stage C, with portal vein thrombosis (PVT) on baseline imaging, and albumin-bilirubin (ALBI) score of 2. More cases of REILD had bilobar radioembolization compared with unilobar treatment. The median absorbed dose to nontumorous liver was 33.0 and 31.8 Gy for REILD and isolated hyperbilirubinemia, respectively. The median overall survival (mOS) for the REILD group was 5.1 months [interquartile range (IQR): 3.4-8.6 months], while mOS for the isolated hyperbilirubinemia group was 4.3 months (IQR: 2.9-5.3 months). Comparing patients with BCLC stage C in the larger database, those who developed REILD had poorer overall survival outcomes.

[CONCLUSION] Our study observed severe liver toxicity at absorbed doses below the recommended dose thresholds to nontumorous liver. ALBI scores greater than or equal to 2 predicted for postprocedural liver toxicities. Further prospective research is suggested to ascertain a safe absorbed dose threshold, incorporating ALBI, PVT status, and bilobar involvement. Caution is warranted when performing bilobar Y-90 radioembolization in ALBI greater than or equal to 2 patients, even at standard doses.