Induction of hypertrophy of the left hepatic lobe by unilateral right hepatic arterial radioembolization (RE) using 90Y-labeled resin microspheres in patients with right-sided secondary malignant liver tumors.

Abstract

e14630 Background: In patients with unilateral liver tumors who are candidates for extended liver resection but demonstrate insufficient future liver remnant (FLR) size, induction of FLR hypertrophy by contralateral portal vein embolization (PVE) is an established approach but concerns exist regarding tumor progression during the interval from PVE to liver surgery. We hypothesized that unilateral hepatic arterial radioembolization (RE) using 90Y-labelled resin microspheres achieves a similar degree of contralateral hypertrophy as PVE. Methods: 32 patients with right-sided secondary liver cancers (metastases from colorectal [n=20], breast [n=7], head and neck [n=2], and other [n=3] cancers) were treated with unilateral right hepatic arterial RE. Before and 44 (22-81) days following RE MRI-based volumetry of the total liver (TLV), the right (RLV, segments 4-8) and left (LLV, segments 2 and 3) hepatic lobes was performed. TLV, RLV, and LLV as well as the LLV/TLV ratio before and after RE were compared using the Mann-Whitney U-test. Results: Median values for TLV, RLV, LLV, and the LLV/TLV ratio are shown in table. Compared to baseline, RLV and TLV showed no significant change after right hepatic arterial RE (-3.7 [min/max, -37.7/+56.5] per cent [p=0.158] and +3.2 [-16.5/+47.4] per cent [p=0.282], respectively). In contrast, LLV as well as the LLV/TLV ratio were significantly increased after RE (+34.9 [-3.1/+146.2] per cent [p<0.001] and +29.4 [-24.3/+155.3] per cent [p<0.001], respectively). Conclusions: Right hepatic arterial RE achieved superior contralateral liver hypertrophy compared to hypertrophy reported after PVE and may be an alternative to PVE since it provides simultaneous treatment to the liver tumors during the interval from treatment to liver surgery, reducing the risk for tumor progression. These two methods should be directly compared within a prospective trial. [Table: see text]