Regulating factors of liver regeneration after hepatectomy

Zinc supports liver regeneration after partial resection

Objectives

Safe removal of extensive liver tumor burdens depends on regeneration of the remnant liver, which requires a large amount of zinc over a short period of time. We studied how zinc influences regeneration.

Material and Methods

We measured perioperative serum zinc concentrations after liver cancer diagnosis in 77 patients undergoing hepatectomy to determine how serum zinc affected short-term outcomes and remnant liver regeneration.

Results

Serum zinc concentration at diagnosis showed no correlation with inflammatory or nutritional parameters except for a weak correlation with the lymphocyte-to-monocyte ratio. When patients were divided into a high pre-hepatectomy zinc group (≥75 µg/dL, n= 39, H group) and a low zinc group (<75 µg/dL, n= 38, L group), short-term results such as mortality (p> 0.999), morbidity (p= 0.490), and hospital stay (p= 0.591) did not differ between groups. However, hypertrophy in the future liver remnant after hepatectomy in the H group (127.7 ± 24.7% of original volume) was greater than in the L group (115.9 ± 16.7%, p= 0.024). In a subgroup of patients with extended hepatectomy, hypertrophy was 130.9 ± 26.8% in the H group vs. 116.4 ± 16.5% in the L group (p= 0.037).

Conclusion

Greater serum zinc at diagnosis was associated with greater hypertrophy in the future liver remnant.

Influence of cytokines, circulating markers and growth factors on liver regeneration and post-hepatectomy liver failure: a systematic review and meta-analysis

The pathophysiology of post-hepatectomy liver failure is not entirely understood but is rooted in the disruption of normal hepatocyte regeneration and homeostasis. Current investigations of post-hepatectomy liver failure and regeneration are focused on evaluation of circulating hepatic function parameters (transaminases, cholestasis, and coagulation parameters), volumetry and hepatic hemodynamics. However, identification of biochemical factors associated with regeneration and post hepatectomy liver failure is crucial for understanding the pathophysiology and identification of patients at risk. The objective of the present systematic review was to identify circulating factors associated with liver regeneration and post hepatectomy liver failure in patients undergoing hepatectomy. The quantitative analysis was intended if studies provided sufficient data. Electronic databases (MEDLINE via PubMed, Web of Knowledge, Cochrane Library and WHO International Clinical Trials Registry Platform) were searched for publications on cell signaling factors in liver regeneration and post-hepatectomy liver failure following liver resection in clinical setting. No date restriction was given. No language restriction was used. Studies were assessed using MINORS. This study was registered at PROSPERO (CRD42020165384) prior to data extraction. In total 1953 publications were evaluated for titles and abstracts after exclusion of duplicates. Full texts of 167 studies were further evaluated for inclusion. 26 articles were included in the review and 6 publications were included in the meta-analyses. High levels of serum hyaluronic acid even preoperatively are associated with PHLF but especially increased levels early after resection are predictive of PHLF with high sensitivity and specificity. Postoperative elevation of HA to levels between 100 and 500 ng/ml is increased the risk for PHLF ([OR] = 246.28, 95% [CI]: 11.82 to 5131.83; p = 0.0004) Inteleukin-6 levels show contradicting result in association with organ dysfunction. HGF positively correlates with liver regeneration. Overall, due to heterogeneity, scarcity, observational study design and largely retrospective analysis, the certainty of evidence, assessed with GRADE, is very low. High levels of serum hyaluronic acid show a strong association with PHLF and increased levels after resection are predictive of PHLF with high sensitivity and specificity, even on POD1. Interleukin-6 levels need to be studied further due to contradictive results in association with organ dysfunction. For HGF, no quantitative analysis could be made. Yet, most studies find positive correlation between high HGF levels and regeneration. Prospective studies investigating HGF and other growth factors, hyaluronic acid and interleukins 1 and 6 in correlation with liver regeneration measured sequentially through e.g. volumetry, and liver function parameters, preferably expanding the analysis to include dynamic liver function tests, are needed to sufficiently illustrate the connection between biomolecule levels and clinical outcomes.

Compensatory hypertrophy of the liver after external beam radiotherapy for primary liver cancer

PURPOSE

We investigated whether external beam radiotherapy (EBRT) could induce compensatory liver hypertrophy in liver cancers and assessed related clinical factors.

METHODS

A total of 82 consecutive patients receiving EBRT for hepatocellular carcinoma (n = 77) or cholangiocarcinoma (n = 5) from April 2012 to June 2014 were recruited and divided into two subgroups according to tumor location in the right or left lobe. The left lateral and right lobes were considered as unirradiated volumes accordingly. Total liver volume (TLV), nontumor liver volume (NLV), left and right lobe whole volume (LLWV and RLWV, respectively), volume of liver irradiated < 30 Gy (V_< 30 Gy), Child-Pugh (CPS) score, future liver remnant (FLR) ratio, and percentage of FLR hypertrophy from baseline (%FLR) were assessed.

RESULTS

In the right lobe group, %FLR hypertrophy and LLWV increased significantly at all follow-ups (p < 0.001). %FLR hypertrophy steadily increased until the fourth follow-up. Multivariate analysis showed that the factor associated with maximum %FLR hypertrophy was tumor extent (upper or lower lobe vs. both lobes; p = 0.022). Post-RT treatments including transarterial chemoembolization or hepatic arterial infusion chemotherapy were associated with a CPS increase ≥ 2 (p = 0.002). Analysis of the RT only subgroup also showed a significant increase of %FLR until the fourth follow-up (p < 0.001). In the left lobe group, %FLR hypertrophy and RLWV showed no significant changes during follow-up.

CONCLUSION

Significant compensatory hypertrophy of the liver was observed, with a steady increase of %FLR hypertrophy until the fourth follow-up (median: 396 days). Locally advanced tumors extending across the upper and lower right lobe were a significant factor for compensating hypertrophy after EBRT.

Portal vein embolization with n-butyl-cyanoacrylate through an ipsilateral approach before major hepatectomy: single center analysis of 50 consecutive patients

Purpose

To evaluate the efficacy of portal vein embolization (PVE) with n-Butyl-cyanoacrylate (NBCA) through an ipsilateral approach before major hepatectomy. Secondary end-points were PVE safety, liver resection and patient outcome.

Methods

Over a 5-year period 50 non-cirrhotic consecutive patients were included with primary or secondary liver cancer treatable by hepatectomy with a liver remnant (FLR) volume less than 25% or less than 40% in diseased livers.

Results

There were 37 men and 13 women with a mean age of 57 years. Colorectal liver metastases were the most frequent tumor and patients were previously exposed to chemotherapy. FLR increased from 422 ml to 629 ml (P < 0.001) after PVE, corresponding to anincrease of 52%. The FLR ratio increased from 29.6% to 42.3% (P < 0.001). Kinetic growth rate was 2.98%/week. A negative association was observed between increase in the FLR and FLR ratio and FLR volume before PVE (P = 0.002). In 31 patients hepatectomy was accomplished and only one patient presented with liver insufficiency within 30 days after surgery.

Conclusions

PVE with NBCA through an ipsilateral puncture is effective before major hepatectomy. Meticulous attention is needed especially near the end of the embolization procedure to avoid complications.

Trial registration

Clinical Study ISRCTN registration number: ISRCTN39855523. Registered March 13th 2017.

Volume regeneration of segments 2 and 3 after right portal vein embolization in patients undergoing two-stage hepatectomy

BACKGROUND

The impact of first-stage resection on volume regeneration of segments 2 and 3 (2 + 3) after right portal vein embolization (RPVE) in patients undergoing two-stage right hepatectomy has not been investigated.

METHOD

Volume data for segments 2 + 3 were compared between 44 patients undergoing two-stage hepatectomy and 116 undergoing single-stage hepatectomy after RPVE.

RESULTS

The degree of hypertrophy (difference between standardized volume of segments 2 + 3 before and after RPVE) and kinetic growth rate (degree of hypertrophy at initial volume assessment divided by the number of weeks elapsed after RPVE) were significantly lower in patients undergoing two-stage hepatectomy (median 8.6 vs 10.5% [p = 0.01] and 1.7 vs 2.4% [p < 0.01], respectively). Resection volume during first-stage resection was negatively correlated with standardized volume increase from the volume before first-stage resection (R (2) 0.546, p < 0.01). In patients undergoing two-stage hepatectomy after RPVE with segment 4 embolization, the degree of hypertrophy and kinetic growth rate were similar to those in patients undergoing single-stage hepatectomy (p = 0.17 and p = 0.08, respectively).

CONCLUSION

In patients undergoing two-stage hepatectomy, first-stage resection impairs the dynamics of volume regeneration of segments 2 + 3 after RPVE. When two-stage extended right hepatectomy is planned, additional embolization of segment 4 provides volume hypertrophy similar to that in patients undergoing single-stage hepatectomy.

Limiting factors for liver regeneration after a major hepatic resection for colorectal cancer metastases

BACKGROUND

Chemotherapy before resection of colorectal metastases in the liver is extensively used and has been shown to induce histopathological changes in the liver parenchyma, although little is known about the effect of chemotherapy on liver regeneration. The aim of this study was to determine if pre-operative chemotherapy influences the regenerated liver volume after a major liver resection.

PATIENTS AND METHODS

This retrospective cohort study included 74 patients subjected to a major liver resection for colorectal metastases. Patients were divided into two groups depending on whether they had been treated with chemotherapy less than 3 months before surgery or not. Liver volumes were measured before and 1 year after resection.

RESULTS

Pre-operative chemotherapy reduced volumetric liver regeneration (83 ± 2% versus 91 ± 2%; P = 0.007) as compared with patients without chemotherapy. There was a linear correlation between regenerated volume and time interval between the end of chemotherapy to resection (P = 0.031).

CONCLUSIONS

Pre-operative chemotherapy in patients with colorectal liver metastases negatively affects volume regeneration after a partial hepatectomy. The time interval between chemotherapy and surgery determines the impact of these affects.

Equivalent outcomes after anatomical and non-anatomical resection of small hepatocellular carcinoma in patients with preserved liver function

BACKGROUND

Although anatomical resection (AR) is considered better than non-anatomical resection (NAR) for the treatment for hepatocellular carcinoma (HCC), there is only limited evidence in support of this argument.

AIM

The aim of this study was to investigate whether AR is superior to NAR regarding postoperative outcomes in patients with small solitary HCC and preserved liver function.

METHODS

The study subjects were 92 curatively-resected patients with adequate liver function reserve (indocyanine green retention rate at 15 min <15%, prothrombin time >70%, serum albumin >3.5 g/dl) and macroscopically small (≤3.0 cm) solitary HCC without macroscopic vascular invasion; 30 patients underwent AR and 62 patients NAR. Postoperative short-term outcomes including mortality and morbidity and long-term outcomes were compared in the two groups.

RESULTS

There was no significant difference in clinicopathological background in the two groups. Although resected liver volume was significantly larger in the AR group than the NAR group (p < 0.0001), no significant differences were detected in the incidence of mortality or morbidity. For long-term outcomes, there were no significant differences between the two groups in disease-free survival or overall survival. Multivariate analysis showed that the extent of surgical procedure was not a significant prognostic factor for disease-free or overall survival.

CONCLUSIONS

AR of a solitary small HCC did not carry postoperative outcome advantages compared with NAR in patients with preserved liver function. We recommend NAR for hepatic resection of small solitary HCC in patients with preserved liver function.

Serum HGF and TGF-beta1 levels after right portal vein embolization

AIM

The changes in the serum hepatocyte growth factor (HGF) and transforming growth factor (TGF)-beta1 levels after portal vein embolization (PVE), and their clinical significance, remain unclear and we aimed to assess their relationship.

METHODS

The serum HGF and TGF-beta1 levels were prospectively measured in 22 patients before and 1, 3, 5, 7, and 14 day after right PVE. Computed tomographic volumetry was performed before and at a mean of 26 +/- 4 days after right PVE.

RESULTS

Three to four weeks after right PVE, the volume of embolized lobe significantly decreased from 704 +/- 157 cm(3) before PVE to 539 +/- 168 cm(3) after PVE (P < 0.001). In contrast, the volume of nonembolized lobe significantly increased from 426 +/- 142 cm(3) to 560 +/- 165 cm(3) (P < 0.001). The serum HGF level significantly increased on day 3 after PVE compared with the pretreatment level (P = 0.005), while the serum TGF-beta1 level significantly decreased and reached its lowest value on day 3 (P = 0.002). Using Pearson's correlation analysis, we found that the serum HGF and TGF-beta1 levels on day 14 negatively associated with the large hypertrophic response in the nonembolized lobe (HGF: r = -0.490, P = 0.021; TGF-beta1: r = -0.473, P = 0.026).

CONCLUSIONS

PVE induced an increase in the serum HGF level and reduced the serum TGF-beta1 level. Measurement of serum HGF and TGF-beta1 levels on day 14 after right PVE may be useful for assessment of the future liver hypertrophy in nonembolized lobe after right PVE.

Predictive factors for hypertrophy of the future remnant liver after selective portal vein embolization

BACKGROUND

To analyze predictive factors of hypertrophy of the nonembolized future remnant liver (FRL) after transhepatic preoperative portal vein embolization (PVE) of the liver to be resected.

MATERIALS AND METHODS

Age, gender, indocyanin green clearance test, chemotherapy before PVE, type of chemotherapy, operators, extent of PVE, radiofrequency ablation (RFA) associated with PVE, time delay between PVE and surgery, and platelet count were retrospectively evaluated as predictive factors for hypertrophy of FRL in 107 patients with malignant disease in noncirrhotic liver. PVE targeted the right liver lobe [n = 70] or the right liver lobe and segment IV [n = 37] when FRL/total liver volume ratio was below 25% in healthy liver or 40% in altered liver.

RESULTS

After PVE, FRL volume significantly increased by 69%, from 344 +/- 156 cm(3) to 543 +/- 192 cm(3) (P < .0001). The degree of hypertrophy was negatively correlated with FRL volume (correlation coefficient = -0.55, P < .0001) and FRL/TFL ratio (correlation coefficient = -0.52, P < .0001) before PVE. Patients, who have undergone chemotherapy with platin agents prior to PVE, demonstrated lower hypertrophy (P = .048).

CONCLUSION

Hypertrophy after PVE is inversely correlated to initial FRL volume. Hypertrophy of the liver might be influenced by the systemic chemotherapeutic received before PVE.

Influence of chemotherapy on liver regeneration induced by portal vein embolization or first hepatectomy of a staged procedure for colorectal liver metastases

BACKGROUND

Although portal vein embolization (PVE) and staged hepatectomy (StHx), as well as prehepatectomy chemotherapy, have improved the resectability rate of patients with multiple bilobar colorectal liver metastases, the impact of prehepatectomy chemotherapy on liver hypertrophy following PVE and/or StHx has remained unclear.

METHODS

Sixty patients who underwent PVE followed by one-stage hepatectomy and StHx with or without PVE were analyzed. Liver hypertrophy following PVE and/or the first hepatectomy of StHx and the clinical course after final hepatectomy was compared between patients with and without prehepatectomy chemotherapy.

RESULTS

No difference of volume of the future liver remnant (FLR) before or after the procedure was seen between the chemotherapy group and the nonchemotherapy group. Even in 38 patients who underwent right PVE prior to a planned right hemihepatectomy, the chemotherapy group (n = 14) and the nonchemotherapy group (n = 24) were comparable in terms of volumes of FLR before (P = 0.71) and after (P = 0.29) PVE and posthepatectomy courses. However, the liver hypertrophy ratio for patients showing steatosis in adjacent nonmalignant liver parenchyma, which frequently is induced by chemotherapy, was lower than that for patients without steatosis (P = 0.04).

CONCLUSIONS

Although prehepatectomy chemotherapy did not impair liver hypertrophy, PVE and/or StHx accompanied by prehepatectomy chemotherapy should be performed with particular care to minimize risk of liver failure after the procedure.

Anatomic versus limited nonanatomic resection for solitary hepatocellular carcinoma

BACKGROUND

Although anatomic liver resection is preferred when treating hepatocellular carcinoma (HCC), evidence that it improves survival when compared with an adequate nonanatomic resection is lacking. The purpose of this study was to compare the survival impact of anatomic versus nonanatomic resection in patients with solitary HCC.

PATIENTS AND METHODS

Clinicopathologic data were available for 125 patients who underwent hepatectomy for a solitary HCC confined to 1 or 2 Couinaud's segments. These patients were divided into 2 groups based on the hepatectomy procedure: anatomic (n = 83) and nonanatomic (n = 42) resection.

RESULTS

No differences were detected either in the hepatic recurrence rates (P = .38) or in the overall survival rates (P = .34) between the anatomic group and the nonanatomic group. The hepatectomy procedure (anatomic vs nonanatomic resection) did not affect survival in either univariate (P = 0.34) or multivariate analysis (relative risk, 1.574; P = .22). The proportion of patients who survived after recurrence was greater in the nonanatomic (15/42) than the anatomic group (13/83; P = .049), and the median survival time after recurrence was greater in patients who underwent nonanatomic resection (991 days; range, 131-4073 days) than in patients with anatomic resection (310 days; range, 48-1887 days; P = .045).

CONCLUSIONS

No superiority was seen in survival when HCC was treated by anatomic resection. Maintaining adequate liver function regardless of whether the resection is anatomic or not may be of greater importance.

Regeneration after two-stage hepatectomy vs. repeat resection for colorectal metastasis recurrence

BACKGROUND

Two-stage hepatectomy aims to minimize liver failure risk by performing a second resection after regeneration, assuming that remnant liver hypertrophy after the second resection is similar to that seen in repeat hepatectomy, yet the impact of a two-stage strategy on liver volume and function remains to be demonstrated.

PATIENTS AND METHODS

Twenty patients undergoing two-stage hepatectomy for multiple colorectal cancer metastases and 21 patients with more than two sections of liver parenchyma totally removed by repeat liver resections for recurrence were enrolled. Liver volumes after final hepatectomy and postoperative liver function were compared.

RESULTS

Median total liver volumes before initial hepatectomy and after final hepatectomy of multiple resections were 942 and 863 ml in patients with repeat hepatectomy, whereas volumes at corresponding time points were 957 and 777 ml in patients with two-stage hepatectomy. The ratio of total liver volume after both hepatectomies to preoperative volume in the two-stage group (81.7%) was lower than that in the repeat resection group (92.0%, P = 0.027). Greater aspartate aminotransferase and prothrombin time and lower platelet count 1 month postoperatively and lower albumin at 6 months were evident after two-stage hepatectomy compared with repeat hepatectomy.

CONCLUSIONS

Two-stage hepatectomy is characterized by diminished hepatic regenerative capacity and postoperative liver function.

Liver regeneration after major hepatectomy for biliary cancer

BACKGROUND

The aim of this study was to evaluate serial changes in liver volume after major hepatectomy for biliary cancer and to elucidate clinical factors influencing liver regeneration.

METHODS

Serial changes in liver volume were determined, using computed tomography, in 81 patients with biliary cancer who underwent right hepatic lobectomy or more extensive liver resection with or without portal vein resection and/or pancreatoduodenectomy. Possible factors influencing liver regeneration were evaluated by univariate and multivariate analyses.

RESULTS

The remnant mean(s.d.) liver volume was 41(8) per cent straight after hepatectomy. This increased rapidly to 59(9) per cent within 2 weeks, then increased more slowly, finally reaching a plateau at 74(12) per cent about 1 year after hepatectomy. The regeneration rate within the first 2 weeks was 16(8) cm3/day and was not related to the extent of posthepatectomy liver dysfunction. On multivariate analysis, the extent of liver resection (P < 0.001), body surface area (P = 0.02), combined portal vein resection (P = 0.024) and preoperative portal vein embolization (P = 0.047) were significantly associated with the liver regeneration rate within the first 2 weeks. In addition, body surface area (P < 0.001) and liver function expressed as plasma clearance rate of indocyanine green (P = 0.01) were significant determinants of final liver volume 1 year after hepatectomy.

CONCLUSION

The liver regenerates rapidly in the first 2 weeks after major hepatectomy for biliary cancer. This early regeneration is influenced by four clinical factors. Thereafter, liver regeneration progresses slowly and stops when the liver is three-quarters of its original volume, approximately 6 months to 1 year after hepatectomy.

Dietary nucleotides have cytoprotective properties in rat liver damaged by thioacetamide

Liver cirrhosis has been induced with thioacetamide administered via different routes in rats and other species. The oral intake of thioacetamide causes nodular liver cirrhosis in rats characterized by extensive fibrosis occupying most of the hepatic parenchyma. To characterize the cytological features of cirrhosis induced by thioacetamide, and the degree of recovery obtained with dietary nucleotides, we made a morphometric study of the hepatocytes in rats administered 300 mg/l of thioacetamide for 4 months, and in rats receiving the same hepatotoxic treatment but allowed a 2-weeks recovery period on a nucleotide-free diet or a 250 mg/100 g nucleotide-supplemented diet. Thioacetamide caused to cell damage and affected the ultrastructure of hepatocytes leading to a decrease in cytoplasmic area together with increased nuclear and nucleolar size. Dietary supplementation with nucleotides favoured recovery, restoring the cytoplasmic (TN=491.7+/-9.6 vs TAA=305.1+/-3.7), nuclear (73.6+/-2.8 vs 97.4+/-2.9), and nucleolar area of damaged hepatocytes (5.6+/-0.3 vs 14.0+/-0.9). The injury from thioacetamide intake increased liver collagen, but dietary nucleotides prevented hepatic deposition of this protein. This study supports the hypothesis that dietary supplementation with nucleotides is decisive in ensuring hepatocyte recovery after thioacetamide-induced liver damage, and that dietary nucleotides have antifibrotic properties.

Multiple hilar cysts of the liver in patients with alcoholic cirrhosis: report of three cases

The present report concerns the clinicopathological study of three patients with alcoholic cirrhosis (a 40-year-old man, a 52-year-old woman and a 48-year-old man) who had multiple cysts along their intrahepatic bile ducts. The cysts were visible on gross examination of the liver and, in two cases, an enlargement of the cysts had been detected in abdominal computed tomography scans performed 1 year apart. Histologically, the cysts consisted of proliferating and dilated peribiliary glands. The cysts occasionally compressed the original bile ducts. The latter showed mucosal hyperplasia with antral-type gland metaplasia. Neoplastic changes and necroinflammation were not seen. Immunohistochemical assays revealed that the peribiliary glands and antral-type glands expressed not only cytokeratin and carbohydrate antigen 19-9, but also c-MET protein, the hepatocyte growth factor receptor which may be related, at least in part, to the cystic dilatation of the peribiliary glands.