Liver Venous Deprivation (LVD) Versus Portal Vein Embolization (PVE) Alone Prior to Extended Hepatectomy: A Matched Pair Analysis

Abstract

Background: To investigate whether liver venous deprivation (LVD) as simultaneous, portal vein (PVE) and right hepatic vein embolization offers advantages in terms of hypertrophy induction before extended hepatectomy in non-cirrhotic liver.

Materials and methods: Between June 2018 and August 2019, 20 patients were recruited for a prospective, non-randomized study to investigate the efficacy of LVD. After screening of 134 patients treated using PVE alone from January 2015 to August 2019, 14 directly matched pairs regarding tumor entity (cholangiocarcinoma, CC and colorectal carcinoma, CRC) and hypertrophy time (defined as time from embolization to follow-up imaging) were identified. In both treatment groups, the same experienced reader (> 5 years experience) performed imaging-based measurement of the volumes of liver segments of the future liver remnant (FLR) prior to embolization and after the standard clinical hypertrophy interval (~ 30 days), before surgery. Percentage growth of segments was calculated and compared.

Results: After matched follow-up periods (mean of 30.5 days), there were no statistically significant differences in relative hypertrophy of FLRs. Mean ± standard deviation relative hypertrophy rates for LVD/PVE were 59 ± 29.6%/54.1 ± 27.6% (p = 0.637) for segments II + III and 48.2 ± 22.2%/44.9 ± 28.9% (p = 0.719) for segments II-IV, respectively.

Conclusions: LVD had no significant advantages over the standard method (PVE alone) in terms of hypertrophy induction of the FLR before extended hepatectomy in this study population.

Keywords: Extended hepatectomy; Future liver remnant (FLR); Liver venous deprivation (LVD); Portal vein embolization (PVE); Right hepatic vein embolization (rHVE).

Fig. 1

Flowchart study population. From June 2018 to August 2019, 20 patients with an indication for extended right hepatectomy and PVE at this center agreed to participate as study group with LVD. Two patients had to be excluded from LVD—one patient withdrew his consent to rHVE during the intervention and one patient could not be treated due to hepatic abscess formation related to a septic event, resulting in 18 completed LVDs. Subsequently, 134 consecutive patients who underwent PVE before extended right hepatectomy were retrospectively screened from January 2015 to August 2019 for direct matching regarding hypertrophy time (defined as time from embolization to follow-up imaging) and tumor entity. 14 matches were identified and loss of 4 LVD cases was accepted. There was no significant difference regarding liver resection rates between the groups (PVE: 10 of 14, LVD: 9 of 14, p = 0.500). In all other cases where surgery was not completed, tumor progression occurred during the hypertrophy interval, and systemic therapies were used instead. Portal vein embolization (PVE), liver vein deprivation (LVD), right hepatic vein embolization (rHVE), future liver remnant (FLR)

Fig. 2

Example case. A 75-year-old man with cholangiocarcinoma (CC, Klatskin tumor type IIIa). Total radiation dose applied during intervention: 64.6 Gy*cm², fluoroscopic time of intervention: 17 min; hypertrophy time: 28 days; relative hypertrophy rate of liver segments II + III: 68.2%, relative hypertrophy rate of liver segments II–IV: 68.1%; LiMAx score before surgery: 291 µg/h/kg. a Digital subtraction angiography (DSA) of the portal vein before embolization (PVE) after ultrasound-guided, transhepatic puncture. b DSA portography after embolization of the right portal vein branch with coils and particles. c DSA venography of the right hepatic vein after ultrasound-guided transhepatic puncture. d Verification of catheter position in the right hepatic vein by cone-beam CT. e Fluoroscopic positioning of the plug in the central right hepatic vein. f DSA of embolization of the puncture tract including peripheral vascular segments with a mixture (ratio of 2:1) of n-butyl-2-cyanoacrylate and ethiodized oil. g Planning CT before LVD in venous contrast phase. h CT in venous phase after hypertrophy time with verification of correct plug positioning in the right hepatic vein. i Planning CT before intervention in coronal orientation. j CT after hypertrophy time in coronal orientation with subjective hypertrophy of the left liver lobe. FLR hypertrophy (segments II + III) in this case was 68%. k CT after extended right hepatectomy horizontal arrows: coils, vertical arrows: plug

Fig. 3

LiMAx scores before surgery. Liver function assessed by presurgical mean LiMAx scores shows no significant difference between the two groups (PVE: 363.4 ± 139.7 µg/h/kg, CI: 282.8–444.1 µg/h/kg; LVD: 377.1 ± 170.5 µg/h/kg, CI: 278.7–475.6 µg/h/kg; p = 0.820)

Fig. 4

Radiation doses applied during interventions expressed as dose area product (Gray*cm²). Although a wider range of doses is apparent in the LVD group, mean applied doses do not differ significantly between the two groups (LVD: 268.9 ± 313.1 Gy*cm², CI: 88.1–449.6 Gy*cm²; PVE: 186.1 ± 145 Gy*cm², CI: 102.2–269.9 Gy*cm²; p = 0.431)

Fig. 5

Hypertrophy rates of future liver remnant (FLR). LVD does not significantly improve mean relative hypertrophy of the future liver remnant (FLR). a Hypertrophy rate for segment II and III in % (PVE: 54.1 ± 27.6%, CI: 38.1–70%; LVD: 59 ± 29.6%, CI: 42–76.1%; p = 0.637); b hypertrophy rate for segment II, III and IV in % (PVE: 44.9 ± 28.9%, CI: 28.2–61.6%; LVD: 48.2 ± 22.2%, CI: 35.5–61; p = 0.719)