Kinetic analysis of contralateral liver hypertrophy after radioembolization of primary and metastatic liver tumors

Abstract Background Radioembolization induces liver hypertrophy, although the extent and rate of hypertrophy are unknown. Our goal was to examine the kinetics of contralateral liver hypertrophy after transarterial radioembolization. Methods A retrospective study (2010–2014) of treatment-naive patients with primary/secondary liver malignancies undergoing right lobe radioembolization was performed. Computed tomography volumetry was performed before and 1, 3, and 6 months after radioembolization. Outcomes of interest were left lobe (standardized future liver remnant) degree of hypertrophy, kinetic growth rate, and ability to reach goal standardized future liver remnant ≥40%. Medians were compared with the Kruskall-Wallis test. Time to event analysis was used to estimate time to reach goal standardized future liver remnant. Results In the study, 25 patients were included. At 1, 3, and 6 months, median degree of hypertrophy was 4%, 8%, and 12% ( P P  = .015), and kinetic growth rate was 0.8%, 0.5%, and 0.4%/week ( P  = .002). In patients with baseline standardized future liver remnant N =  16), median time to reach standardized future liver remnant ≥40% was 7.3 months, with 75% accomplishing standardized future liver remnant ≥40% at 8.2 months. Conclusion Radioembolization induces hypertrophy of the contralateral lobe to a similar extent as existing methods, although at a lower rate. The role of radioembolization as a dual therapy (neoadjuvant and hypetrophy-inducing) for selected patients needs to be studied. (Surgery 2017;160:XXX-XXX.)