Histological and radiological analysis of simultaneous dual hepatic vein embolization for right-sided major hepatectomy

PURPOSE

Simultaneous dual hepatic vein embolization (DHVE) has been proposed for safe right-sided hepatectomy, with good results for liver hypertrophy and function. However, the histological and radiological findings of DHVE have not been thoroughly investigated.

METHODS

This study included 14 patients who underwent DHVE before right-sided major hepatectomy. DHVE was performed if the future liver remnant was < 35% or borderline, but with concomitant vascular resection. The liver function was assessed using the signal intensity on Gd-EOB-DTPA-MRI. A histological evaluation of the area of DHVE and portal vein embolization (PVE) were performed.

RESULTS

The median pre- and post-functional liver remnants were 363 ml and 498 ml, respectively (p < 0.001). The median growth rate was 48.6%, and there was no post-hepatectomy liver failure in the patients who underwent DHVE. The signal intensity ratio in the area of DHVE was lower than that in the areas of PVE and the remnant liver (p < 0.01). The degree of congestion and necrosis was greater in the area of DHVE than in the area of PVE alone (p < 0.01 and p = 0.04, respectively).

CONCLUSIONS

We observed good liver hypertrophy after DHVE and histological and radiological changes in the area of DHVE. Our findings provide a compelling rationale for further investigation of the mechanism of liver hypertrophy in DHVE.

Portal vein embolization failure: Current strategies and future perspectives to improve liver hypertrophy before major oncological liver resection

Portal vein embolization (PVE) is currently considered the standard of care to improve the volume of an inadequate future remnant liver (FRL) and decrease the risk of post-hepatectomy liver failure (PHLF). PHLF remains a significant limitation in performing major liver surgery and is the main cause of mortality after resection. The degree of hypertrophy obtained after PVE is variable and depends on multiple factors. Up to 20% of patients fail to undergo the planned surgery because of either an inadequate FRL growth or tumor progression after the PVE procedure (usually 6-8 wk are needed before surgery). The management of PVE failure is still debated, with a lack of consensus regarding the best clinical strategy. Different additional techniques have been proposed, such as sequential transarterial chemoembolization followed by PVE, segment 4 PVE, intra-portal administration of stem cells, dietary supplementation, and hepatic vein embolization. The aim of this review is to summarize the up-to-date strategies to overcome such difficult situations and discuss future perspectives on improving FRL hypertrophy.

Simultaneous portal and hepatic vein embolization is better than portal embolization or ALPPS for hypertrophy of future liver remnant before major hepatectomy: A systematic review and network meta-analysis

BACKGROUND

Post-hepatectomy liver failure (PHLF) is the Achilles' heel of hepatic resection for colorectal liver metastases. The most commonly used procedure to generate hypertrophy of the functional liver remnant (FLR) is portal vein embolization (PVE), which does not always lead to successful hypertrophy. Associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) has been proposed to overcome the limitations of PVE. Liver venous deprivation (LVD), a technique that includes simultaneous portal and hepatic vein embolization, has also been proposed as an alternative to ALPPS. The present study aimed to conduct a systematic review as the first network meta-analysis to compare the efficacy, effectiveness, and safety of the three regenerative techniques.

DATA SOURCES

A systematic search for literature was conducted using the electronic databases Embase, PubMed (MEDLINE), Google Scholar and Cochrane.

RESULTS

The time to operation was significantly shorter in the ALPPS cohort than in the PVE and LVD cohorts by 27 and 22 days, respectively. Intraoperative parameters of blood loss and the Pringle maneuver demonstrated non-significant differences between the PVE and LVD cohorts. There was evidence of a significantly higher FLR hypertrophy rate in the ALPPS cohort when compared to the PVE cohort, but non-significant differences were observed when compared to the LVD cohort. Notably, the LVD cohort demonstrated a significantly better FLR/body weight (BW) ratio compared to both the ALPPS and PVE cohorts. Both the PVE and LVD cohorts demonstrated significantly lower major morbidity rates compared to the ALPPS cohort. The LVD cohort also demonstrated a significantly lower 90-day mortality rate compared to both the PVE and ALPPS cohorts.

CONCLUSIONS

LVD in adequately selected patients may induce adequate and profound FLR hypertrophy before major hepatectomy. Present evidence demonstrated significantly lower major morbidity and mortality rates in the LVD cohort than in the ALPPS and PVE cohorts.

Effect of Portal Vein Ligation Plus Venous Congestion on Liver Regeneration in Rats

INTRODUCTION AND AIM

We developed a rat model of portal vein ligation (PVL) with venous congestion (PVL+C) to investigate beneficial effect PVL plus congestion for regeneration of intact liver segments.

MATERIALS AND METHODS

In the PVL group, portal vein branches were ligated except the caudate lobe (CL). In the PVL + C group, the left lateral hepatic vein was ligated in addition to PVL. Chronological changes in the following variables were compared among the groups: CL weight to body weight ratio (CL/BW), embolized liver weight to body weight ratio (EL/BW), histological findings of the embolized/non-embolized liver, and expression of several mediators that affect liver regeneration in the non-embolized liver.

RESULTS

Weight regeneration of CL continued up to postoperative day (POD)7 in PVL + C, but terminated at POD2 in PVL. CL/BW at POD7 was significantly higher in PVL + C than in PVL (2.41 ± 0.33% vs. 1.22 ± 0.18%, P < 0.01). In contrast, EL/BW continued to decrease up to POD7 in PVL + C but reached nadir at POD2 in PVL. Furthermore, EL/BW at POD7 was significantly smaller in PVL + C than in PVL (0.35 ± 0.03% vs. 0.67 ± 0.08%, P < 0.01). Histologically-proven injury in the embolized liver was more severe in PVL + C than in PVL. Expression of Ki-67, IL-6, TNF -a, and HGF were greater and/or more prolonged in PVL + C than in PVL.

CONCLUSIONS

Our rat model of PVL + C was considered useful for investigating the beneficial effect of congestion in addition to PVC. PVL + C caused increased devastation of the embolized liver, and higher and more prolonged expression of factors promoting liver regeneration in the non-embolized liver than in PVL.