Objective: This retrospective study aimed to assess the correlation between absorbed doses using 90Yttrium (90Y) radioembolization and liver function test results in patients with primary or metastatic liver malignancies.
Methods: This study involved 35 patients diagnosed with primary or metastatic liver cancer who underwent treatment with 90Y glass microspheres. Absorbed doses of the tumor and perfused tissue were calculated using voxel-based dosimetry. Albumin-bilirubin (ALBI) scores were calculated before treatment and at 2 and 4 weeks post-treatment. Associations between the absorbed dose and ALBI scores were analyzed.
Results: Thirty-five cases were included in the study. The median radiation doses were 618 Gy for tumors, 497 Gy for the total perfused liver, 281 Gy for the perfused normal liver, 8.5 Gy for the normal liver, and 52.5 Gy for the total liver. Before treatment, 28 (80%) patients had grade 1 ALBI scores, whereas the remainder had grade 2 scores. In two patients, ALBI scores increased to grade 2 during the second week of treatment. Treatment response correlated with partial regression. Although their absorbed doses were not significantly higher than those of other cases (618/550 Gy for tumors, 116/97 Gy for perfused normal tissue, 12/8.5 Gy for normal liver), their tumor-to-whole liver ratios were significantly higher than those of other cases (27-35%). In one patient, the score increased to grade 2 in the fourth week of treatment. However, in this case, liver function failure was attributed to progressive disease post-treatment. None of the grade 2 patients’ scores increased to grade 3.
Conclusion: The study concluded that, through voxel-based dosimetry and a selective treatment approach, higher tumor doses with low absorbed doses in the whole liver were safe.