Hepatic volume changes induced by radioembolization with 90Y resin microspheres. A single-centre study

Lobar radioembolization (RE) of the liver can result in reduction in volume of the ipsilateral lobe as well as hypertrophy of the contralateral lobe. Theoretically, hypertrophy of the contralateral liver lobe after RE could increase the chance of a successful liver resection, especially in patients with limited liver function reserve. The aim of this preliminary study was to evaluate the early effects of RE with resin microspheres on the volumes of the liver lobes and spleen. We retrospectively investigated 24 patients (12 women, 44-78 years old) with different types of cancer and liver-dominant metastatic disease who had undergone RE of the liver with resin microspheres. Changes in the volumes of the liver lobes and spleen were quantified by CT before and about 4 to 8 weeks after treatment. Of the 24 patients, 17 suffered from metastases in both liver lobes (group A) and 7 had metastases only in the right liver lobe (group B). The patients in the group A underwent sequential treatment starting with the right liver lobe. The median administered dose was 1.75 GBq. RE was associated with a median increase in volume of the left liver lobe of 34 % (P < 0.001) and a median decrease in volume of the right liver lobe of 11 % (P = 0.03). The volume of the spleen showed a median increase of 17 % (P = 0.01). Separate analysis of the two groups showed a median increases in volume of the left liver lobe of 30 % (P = 0.001) in group A and 70 % (P = 0.01) in group B. There was no correlation between the injected dose and the volume alteration (r = 0.1-0.3). RE of the right liver lobe with resin microspheres caused a significant increase in the volume of the left liver lobe. This may allow liver resection in patients with metastases in the right liver lobe and a small left liver lobe.