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.

Transarterial embolization is an acceptable bridging therapy to hepatocellular carcinoma prior to liver transplantation

BACKGROUND Hepatocellular carcinoma(HCC)is an aggressive malignant neoplasm that requires liver transplantation(LT).Despite patients with HCC being prioritized by most organ allocation systems worldwide,they still have to wait for long periods.Locoregional therapies(LRTs)are employed as bridging therapies in patients with HCC awaiting LT.Although largely used in the past,transarterial embolization(TAE)has been replaced by transarterial chemoembolization(TACE).However,the superiority of TACE over TAE has not been consistently shown in the literature.AIM To compare the outcomes of TACE and TAE in patients with HCC awaiting LT.METHODS All consecutive patients with HCC awaiting LT between 2011 and 2020 at a single center were included.All patients underwent LRT with either TACE or TAE.Some patients also underwent percutaneous ethanol injection(PEI),concom-itantly or in different treatment sessions.The choice of LRT for each HCC nodule was determined by a multidisciplinary consensus.The primary outcome was waitlist dropout due to tumor progression,and the secondary outcome was the occurrence of adverse events.In the subset of patients who underwent LT,complete pathological response and post-transplant recurrence-free survival were also assessed.RESULTS Twelve(18.5%)patients in the TACE group(only TACE and TACE+PEI;n=65)and 3(7.9%)patients in the TAE group(only TAE and TAE+PEI;n=38)dropped out of the waitlist due to tumor progression(P log-rank test=0.29).Adverse events occurred in 8(12.3%)and 2(5.3%)patients in the TACE and TAE groups,respectively(P=0.316).Forty-eight(73.8%)of the 65 patients in the TACE group and 29(76.3%)of the 38 patients in the TAE group underwent LT(P=0.818).Among these patients,complete pathological response was detected in 7(14.6%)and 9(31%)patients in the TACE and TAE groups,respectively(P=0.145).Post-LT,HCC recurred in 9(18.8%)and 4(13.8%)patients in the TACE and TAE groups,respectively(P=0.756).Posttransplant recurrence-free survival was similar between the groups(P log-rank test=0.71).CONCLUSION Dropout rates and posttransplant recurrence-free survival of TAE were similar to those of TACE in patients with HCC.Our study reinforces the hypothesis that TACE is not superior to TAE as a bridging therapy to LT in patients with HCC.

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.

Expression of MMP-2 in residual VX2 liver tumor after transcatheter arterial embolization combined with portal venous embolization in an animal model

Objective:This study aimed to analyze the effects of transcatheter arterial embolization(TAE)combined with portal venous embolization(PVE)on the expression of MMP-2 in residual VX2 liver tumor tissues,liver function and non-embolic lobe regeneration.Methods:A total of 72 rabbits were randomly divided into Sham,TAE,PVE and TAE+PVE groups(n=18/group).The tissue samples from each group were taken at 6 h,3 days and 7 days after interventional operation,respectively.MMP-2 expression was detected by immunohistochemistry,Real-time PCR,and Western-blotting.The main indicators(such as AST,ATL,and TBIL)of liver function and the volume of non-embolized hepatic lobes were measured in each group after operation.One-way ANOVA and Kruskal-wallis method were used for statistical analysis.Results:The expression of MMP-2 mRNA and protein remained the highest in the Sham group,and the expression of MMP-2 mRNA and protein in TAE,PVE and TAE+PVE groups were successively increased,and the expression of MMP-2 in TAE+PVE group was always significantly higher than TAE group.The AST and ALT levels in each group on day 7 after operation showed a significant declination,and all groups have recovered to the preoperative baseline level and TBIL has a slight fluctuation in each group after operation with no statistical difference.On day 7 after operation,the increasing volume of non-embolized liver lobes in TAE+PVE group showed a more significant effect than those in PVE group,but there was no statistical significance(37.62±1.54 ml VS 36.18±1.15 ml,P=0.881),and its volume was significantly higher than those in the sham group(27.03±1.11 ml).Conclusion:TAE+PVE is considered to be an efficient and safe approach for treating rabbit VX2 liver transplantation tumor,but the expression of MMP-2 increased fastest after TAE+PVE,which might promote tumor cell invasion and metastasis.

Mitoxantrone Ethylcellulose Microspheres for Liver Arte-rial Embolization

Herein,the orthogonal test was used to optimize the preparation conditions and technique of mitoxantrone ethylcellulose microsphere fDHAQ-EC-MS)for liver arterial embolization.The dynamic dialysis method was used to study the drug release characteristics ofthe DRAQ-EC-MS.The suspension of DHAQ-EC-MS for clinical liver arterial embolization was prepared.The results show that the DHAQ-EC-MS is regular in morphology with a mean diameter of 110.24 ± 38.19μm and 86.5% of them within the range of 40-150μm,The drug loading is 12.5% and the embedding ratio is 55.6%. The release characteristics were in accordance with the single exponential model.The drug release equation is log(Y∞-Y)=-0.116t-1.198 × 10￣(-3)(r=0.9992,t(50)=2.6h).The suspension is ofstable physical and chemical properties and is suitable for clinical use.

Evaluation of the effect of partial splenic embolization on platelet values for liver cirrhosis patients with thrombocytopenia

AIM： TO investigate the effect of partial splenic embolization （PSE） on platelet values in liver cirrhosis patients with thrombocytopenia and to determine the effective embolization area for platelet values improvement.METHODS： Blood parameters and liver function indicators were measured on 10 liver cirrhosis patients （6 in Child-Pugh grade A and 4 in grade B） with thrombocytopenia （platelet values 〈 80 × 10^3/μL） before embolization. Computed tomography scan was also needed in advance to acquire the splenic baseline. After 2 to 3 d, angiography and splenic embolization were performed. A second computed tomography scan was made to confirm the embolization area after 2 to 3 wk of embolization. The blood parameters of patients were also examined biweekly during the 1 year follow-up period. RESULTS： According to the computed tomography images after partial splenic embolization, we divided all paUents into two groups： low （〈 30%）, and high （≥ 30%） embolization area groups. The platelet values were increased by 3 times compared to baseline levels after 2 wk of embolization in high embolization area group. In addition, there were significant differences in platelet values between low and high embolization area groups. GPT values decreased significantly in all patients after 2 wk of embolization. The improvement in platelet and GPT values still persisted until 1 year after PSE. In addition, 3 of 4 （75%） Child-Pugh grade B patients progressed to grade A after 2 mo of PSE. The complication rate in 〈 30% and ≥30% embolization area groups was 50% and 100%, respectively. CONCLUSION： Partial splenic embolization is an effective method to improve platelet values and GPT values in liver cirrhosis patients with thrombocytopenia and the ≥ 30% embolization area is meaningful for platelet values improvement. The relationship between the complication rate and embolization area needs further studies.

Impact of pre-operative transarterial embolization on the treatment of hepatocellular carcinoma with liver transplantation

AIM: To determine the effectiveness of pre-liver transplant (LT) transarterial embolization (TAE) in treating hepatocellular carcinoma (HCC) and the patient categories,which are likely to have a good outcome after LT.METHODS: Twenty-nine patients with hepatitis-related cirrhosis and unresectable HCC after LT were studied over a 7-year period. The patients were divided into two groups: group A patients (19/29) received pre-LT TAE,whereas group B (10/29) underwent LT without prior TAE.According to Milan criteria, group A patients were further subdivided into: group A1 (12/19) who met the criteria,and group A2 (7/19) who did not. Patient survivals were compared.RESULTS: In the explanted liver, CT images correlated well with pathological specimens showing that TAE induced massive tumor necrosis (＞85%) in 63.1% of patients in group A and all 7 patients in group A2 exhibited tumor downgrading that met Milan criteria. The overall 5-year actuarial survival rate was 80.6%. The TAE group had a better survival (84% at 5 years) than the non-TAE (75% at 4 years). The 3-year survival of group A2 (83%)was also higher than that of group A1 (79%). Tumor necrosis ＞85% was associated with excellent survival of 100% at 3 years, which was significantly better than the others who showed ＜85% tumor necrosis (57.1% at 3 years) or who did not have TAE (75% at 3 years).CONCLUSION: TAE is an effective treatment for HCC before LT. Excellent long-term survival was achieved in patients that did not fit Milan criteria. Our results broadened and redefined the selection policy for LT among patients with HCC. Meticulous pre-LT TAE helps in further reducing the rate of dropout from waiting lists and should be considered for patients with advanced HCC.

Expression of Hypoxia-inducible Factor-1α in Liver Tumors after Transcatheter Arterial Embolization in an Animal Model

To examine the effect of transcatheter arterial embolization （TAE） of liver tumors on hypoxia-inducible factor-1α （HIF-1α） expression in the residual viable tumor, a total of 30 New Zealand White rabbits implanted with VX2 liver tumor were divided into 2 groups. TAE-treated group animals （n=15） were subjected to TAE with 150–250 μm polyvinyl alcohol particles. Control group animals （n=15） underwent sham embolization with distilled water. Six hours, 3 days or 7 days after TAE, the animals were sacrificed, and samples of tumor and adjacent normal liver tissue were harvested. Expression of HIF-1α protein was examined immunohistochemically. Real-time PCR was performed to examine the HIF-1α mRNA levels. Our results showed that HIF-1α protein was expressed in the VX2 tumors but not in the adjacent normal liver tissue. The HIF-1α-positive tumor cells were located predominantly at the periphery of necrotic tumor regions. The mean levels of HIF-1α protein were significantly higher in TAE-treated tumors than those in control tumors （P=0.002）. Among the three sacrificing time points, the difference in increase in HIF-1α protein was significant between the two groups at the sacrificing time point of 6 h and 3 days after TAE （P=0.020, P=0.031, respectively）, whereas no significant increase was noted 7 days after TAE （P=0.502）. In contrast, although HIF-1α mRNA was expressed in TAE-treated and control VX2 tumors, there existed no significant difference in the HIF-1α mRNA level between the two groups （P=0.372）. It is concluded that TAE of liver tumors increases the expression of HIF-1α at protein level in the residual viable tumor, which could be attributed to hypoxia generated by the procedure.

Effect of hepatic artery embolization on liver hypertrophy response in a rabbit liver VX2tumor model

BACKGROUND:Portal vein embolization not only induces hypertrophy of the non-embolized liver,but also enhances tumor growth.The latter could be prevented by embolizing the hepatic arteries supplying the tumor-bearing liver segments.This study aimed to determine the effects of transcatheter arterial embolization(TAE)on tumor volume and liver regeneration in a rabbit VX2 tumor model.METHODS:Twenty-three rabbits underwent subcapsular tumor implantation with a VX2 tumor.Two weeks after implantation,18 rabbits were used for TAE experiments,5were for sham controls.Tumor response and liver regeneration response of the embolized cranial and non-embolized caudal liver lobes were assessed by CT volumetry,liver to body weight index,and the amount of proliferating hepatocytes.RESULTS:All super-selective arterial tumor embolization procedures were performed successfully.Despite embolization,the tumor volume increased after an initial steady state.The tumor volume after embolization was smaller than that of the sham group,but this difference was not significant.Massive necrosis of the tumor,however,was seen after embolization,without damage of the surrounding liver parenchyma.There was a significant atrophy response of the tumor bearing cranial lobe after super-selective arterial embolization of the tumor with a concomitant hypertrophy response of the non-embolized,caudal lobe.This regeneration response was confirmed histologically by a significantly higher number of proliferating hepatocytes on the Ki-67 stained slides.CONCLUSIONS:Super-selective,bland arterial coil embolization causes massive necrosis of the tumor,despite increase of volume on CT scan.Atrophy of the tumor bearing liver lobe is seen after arterial embolization of the tumor with a concomitant hypertrophy response of the non-embolized lobe,despite absence of histological damage of the tumor-surrounding liver parenchyma.

Radiofrequency ablation in a porcine liver model:Effects of transcatheter arterial embolization with iodized oil on ablation time,maximum output,and coagulation diameter as well as angiographic characteristics

AIM:To evaluate the effects of combined radiofrequen-cy ablation and transcatheter arterial embolization with iodized oil on ablation time,maximum output,coagula-tion diameter,and portal angiography in a porcine liver model. METHODS: Radiofrequency ablation (RFA) was applied to in vivo livers of 10 normal pigs using a 17-gauge 3.0 cm expandable LeVeen RF needle electrode with or with-out transcatheter arterial embolization (TAE) with iodized oil (n = 5). In each animal,2 areas in the liver were ab-lated. Direct portography was performed before and af-ter RFA. Ablation was initiated at an output of 30 W,and continued with an increase of 10 W per minute until roll-off occurred. Ablation time and maximum output until roll-off,and coagulated tissue diameter were compared between the 2 groups. Angiographic changes on portog-raphy before and after ablation were also reviewed. RESULTS: For groups with and without TAE with iodized oil,the ablation times until roll-off were 320.6 ± 30.9 seconds and 445.1 ± 35.9 seconds,respectively,maxi-mum outputs were 69.0 ± 7.38 W and 87.0 ± 4.83 W and maximal diameters of coagulation were 41.7 ± 3.85 mm and 33.2 ± 2.28 mm. Significant reductions of abla-tion time and maximum output,and significantly larger coagulation diameter were obtained with RFA following TAE with iodized oil compared to RFA alone. Portography after RFA following TAE with iodized oil revealed more occlusion of the larger portal branches than with RFA alone. CONCLUSION: RFA following TAE with iodized oil can increase the volume of coagulation necrosis with lower output and shorter ablation time than RFA alone in nor-mal pig liver tissue.

Liver atrophy after percutaneous transhepatic portal embolization occurs in two histological phases: Hepatocellular atrophy followed by apoptosis

AIM To clarify the histological changes associated with liver atrophy after percutaneous transhepatic portalembolization(PTPE) in pigs and humans. METHODS As a preliminary study, we performed pathological examinations of liver specimens from five pigs that had undergone PTPE in a time-dependent model of liver atrophy. In specimens from embolized lobes(EMB) and nonembolized lobes(controls), we measured the portal vein to central vein distance(PV-CV), the area and number of hepatocytes per lobule, and apoptotic activity using the terminal deoxynucleotidyl transferase dU TP nickend labeling assay. Immunohistochemical reactivities were evaluated for light chain 3(LC3) and lysosomal-associated membrane protein 2(LAMP2) as autophagy markers and for glutamine synthetase and cytochrome P450 2 E1(CYP2 E1) as metabolic zonation markers. Samples from ten human livers taken 20-36 d after PTPE were similarly examined. RESULTS PV-CVs and lobule areas did not differ between EMB and controls at day 0, but were lower in EMB than in controls at weeks 2, 4, and 6(P ≤ 0.001). Hepatocyte numbers were not significantly reduced in EMB at day 0 and week 2 but were reduced at weeks 4 and 6(P ≤ 0.05). Apoptotic activity was higher in EMB than in controls at day 0 and week 4. LC3 and LAMP2 staining peaked in EMB at week 2, with no significant difference between EMB and controls at weeks 4 and 6. Glutamine synthetase and CYP2 E1 zonation in EMB at weeks 2, 4, and 6 were narrower than those in controls. Human results were consistent with those of porcine specimens. CONCLUSION The mechanism of liver atrophy after PTPE has two histological phases: Hepatocellular atrophy is likely caused by autophagy in the first 2 wk and apoptosis thereafter.

Portal vein embolization induces compensatory hypertrophy of remnant liver

AIM： To evaluate the effectiveness and safety of different portal vein branch embolization agents in inducing compensatory hypertrophy of the remnant liver and to offer a theoretic basis for clinical portal vein branch embolization. METHODS： Forty-one adult dogs were included in the experiment and divided into four groups. Five dogs served as a control group, 12 as a gelfoam group, 12 as a coil-gelfoam group and 12 as an absolute ethanol group. Left portal vein embolization was performed in each group. The results from the embolization in each group using different embolic agents were compared. The safety of portal vein embolization （PVE） was evaluated by liver function test, computed tomography （CT） and digital subtraction angiography （DSA） of liver and portal veins. Statistical test of variance was performed to analyze the results. RESULTS： Gelfoam used for PVE was inefficient in recanalization of portal vein branch 4 wk after the procedure. The liver volume in groups of coil-gelfoam and absolute ethanol increased 25.1% and 33.18%, respectively. There was no evidence of recanalization of embolized portal vein, hepatic dysfunction, and portal hypertension in coil-gelfoam group and absolute ethanol group. CONCOUSION： Portal vein branch embolization using absolute ethanol and coil-gelfoam could induce atrophy of the embolized lobes and compensatory hypertrophy of the remnant liver. Gelfoam is an inefficient agent.

Gd-EOB-DTPA based magnetic resonance imaging for predicting liver response to portal vein embolization

AIM To evaluate the correlation between degree of kinetic growth(k GR) of the liver following portal vein embolization(PVE) liver and the enhancement of the during the hepatobiliary phase of contrast administration and to evaluate if the enhancement can be used to predict response to PVE prior to the procedure.METHODS Seventeen patients were consented for the prospective study.All patients had an MR of the abdomen with GdEOB-DTPA.Fourteen patients underwent PVE.The correlation between the kG R of the liver and the degree of enhancement was evaluated with linear regression(strong assumptions) and Spearman's correlation test(rank based,no assumptions).The correlation was examined for the whole liver,segments I,VIII,VII,VI,V,IV,right liver and left liver.RESULTS There was no correlation between the degree of enhancement during the hepatobiliary phase and kG R for any segment,lobe of the liver or whole liver(P = 0.19 to 0.91 by Spearman's correlation test).CONCLUSION The relative enhancement of the liver during the hepatobiliary phase with Gd-EOB-DTPA cannot be used to predict the liver response to PVE.

Laparoscopic hepatectomy for liver neoplasms in 15 cases

Objective： The aim of our study was to retrospectively analyze 15 patients＇ clinical materials with laparoscopic resection of liver neoplasms. Methods： From December 2007, a total of 15 patients with liver neoplasms were performed with laparoscopic hepatectomy, and their clinical materials, perioperative dates, postoperative complications, postoperative recovery and short-term curative effects were analyzed and summarized respectively. Results： Laparoscopic hepatectomy （LH） were performed in 15 patients, including 1 case underwent laparoscopic hepatic left Iobectomy, 1 case of left lateral hepatectomy, 13 cases of partial liver resection. Fourteen cases of total laparoscopic liver resections for liver neoplasms, 1 case of hand-assisted laparoscopic liver resection of the tumor, there was no conversion to open approach. Of the 15 patients with liver neoplasms, 13 cases of hepatic neoplasms with the maximum diameter was 8 cm× 8 cm × 9 cm, 9 cases of the borderline micro hepatocellular carcinoma （MHCC） with the diameter not more than 2 cm, 3 cases of hepatic benign tumor. The mean operation time was （120 ± 30） min, and the intraoperative average hemorrhage was 100 mL, beginning to eat and get out of bed following 1-2 days of operation. The average postoperative hospitalization was 8 days, WBC, ALl＇, AST, albumin, bilirubin returned to normal after one week of operation. There were no postoperative complications such as hemorrhage, bile leakage or air embolism etc. Twelve patients with HCC were confirmed by postoperative pathology, 1 case of liver smooth muscle lipoma, 2 case of hepatic hemangioma. By one year of followed-up in 12 cases of HCC, the longest survival was 38 months, and no recurrence or death, 1 year survival rate was 100%. Conclusion： Among the choice of cases, the advantages of LH for liver neoplasms compared with open surgery were less trauma, faster recovery and less blood loss. it is safe and effective for choosing a reasonable surgical indication, especially for peripheral micro hepatocellular carcinoma.

Functional transition:Inconsistently parallel to the increase in future liver remnant volume after preoperative portal vein embolization

BACKGROUND Preoperative portal vein embolization(PVE)is a widely used strategy to enable major hepatectomy in patients with insufficient liver remnant.PVE induces hypertrophy of the future liver remnant(FLR)and a shift of the functional reserve to the FLR.However,whether the increase of the FLR volume(FLRV)corresponds to the functional transition after PVE remains unclear.AIM To investigate the sequential relationship between the increase in FLRV and functional transition after preoperative PVE using 3-dimensional(3D)computed tomography(CT)and 99mTc-galactosyl-human serum albumin(99mTc-GSA)singlephoton emission computed tomography(SPECT)fusion images.METHODS Thirty-three patients who underwent major hepatectomy following PVE at the Department of Gastroenterological Surgery I,Hokkaido University Hospital between October 2013 and March 2018 were enrolled.Three-phase dynamic multidetector CT and 99mTc-GSA SPECT scintigraphy were performed at pre-PVE,and at 1 and 2 wk after PVE;3D 99mTc-GSA SPECT CT-fused images were constructed from the Digital Imaging and Communications in Medicine data using 3D image analysis system.Functional FLRV(FFLRV)was defined as the total liver volume×(FLR volume counts/total liver volume counts)on the 3D 99m Tc-GSA SPECT CT-fused images.The calculated FFLRV was compared with FLRV.RESULTS FFLRV increased by a significantly larger extent than FLRV at 1 and 2 wk after PVE(P<0.01).The increase in FFLRV and FLRV was 55.1%±41.6%and 26.7%±17.8%(P<0.001),respectively,at 1 wk after PVE,and 64.2%±33.3%and 36.8%±18.9%(P<0.001),respectively,at 2 wk after PVE.In 3 of the 33 patients,FFLRV levels decreased below FLRV at 2 wk.One of the three patients showed rapidly progressive fatty changes in FLR.The biopsy at 4 wk after PVE showed macroand micro-vesicular steatosis of more than 40%,which improved to 10%.Radical resection was performed at 13 wk after PVE.The patient recovered uneventfully without any symptoms of pos-toperative liver failure.CONCLUSION The functional transition lagged behind the increase in FLRV after PVE in some cases.Evaluating both volume and function is needed to determine the optimal timing of hepatectomy after PVE.

Will partial splenic embolization followed by splenectomy increase intraoperative bleeding?

BACKGROUND Partial splenic embolization(PSE)has been suggested as an alternative to splenectomy in the treatment of hypersplenism.However,some patients may experience recurrence of hypersplenism after PSE and require splenectomy.Currently,there is a lack of evidence-based medical support regarding whether preoperative PSE followed by splenectomy can reduce the incidence of complications.AIM To investigate the safety and therapeutic efficacy of preoperative PSE followed by splenectomy in patients with cirrhosis and hypersplenism.METHODS Between January 2010 and December 2021,321 consecutive patients with cirrhosis and hypersplenism underwent splenectomy at our department.Based on whether PSE was performed prior to splenectomy,the patients were divided into two groups:PSE group(n=40)and non-PSE group(n=281).Patient characteristics,postoperative complications,and follow-up data were compared between groups.Propensity score matching(PSM)was conducted,and univariable and multivariable analyses were used to establish a nomogram predictive model for intraoperative bleeding(IB).The receiver operating characteristic curve,Hosmer-Lemeshow goodness-of-fit test,and decision curve analysis(DCA)were employed to evaluate the differentiation,calibration,and clinical performance of the model.RESULTS After PSM,the non-PSE group showed significant reductions in hospital stay,intraoperative blood loss,and operation time(all P=0.00).Multivariate analysis revealed that spleen length,portal vein diameter,splenic vein diameter,and history of PSE were independent predictive factors for IB.A nomogram predictive model of IB was constructed,and DCA demonstrated the clinical utility of this model.Both groups exhibited similar results in terms of overall survival during the follow-up period.CONCLUSION Preoperative PSE followed by splenectomy may increase the incidence of IB and a nomogram-based prediction model can predict the occurrence of IB.

Source of blood supply of liver cavernous hemangioma and sclerosis and embolization treatment

AIM To investigate the source of blood supply of carvenous hemangioma of liver (CHL) and provide a feasibile treatment for CHL via hepatic artery. METHODS Ⅰ. Origin of blood supply of CHL: portovenography, hepatic arteriography and portal vein staining were performed in 5 patients. Two casts of hepatic blood vessels from resected specimen were observed. Ⅱ. Clinical data: Among 75 patients (30 males, 45 females, aged 25～57 years with a mean of 37 4). 56 were of solitary type (44 on the right lobe, 12 on the left with 4 having intraparenchymatoma) and 19 were of multiple type (9 on the right, 2 the left, 8 whole liver). Twenty two patients were treated by sclerosis, 50 by embolization via hepatic artery and 3 were excised. RESULTS In 5 cases with portography, the contrast medium did not enter the tumor, the tumor appeared as low denty area and the intrahepatic branches of portal vein were pushed aside. In 5 cases with portal vein staining, the normal liver parenchyma was stained deep blue, and the tumor was not stained. The tumor area appeared as a round vacant cavity in 2 specimen casts. In 72 patients treated with sclerosis a or embolization via hepatic artery or through interventional method, the tumors diminished by 10%～30% in diameter and no tumors grew larger. CONCLUSION The blood supply of CHL originates from the hepatic artery. Tumors treated with sclerosis and emblization decreased in size or got fiberized.

Portal vein embolization effect on colorectal cancer liver metastasis progression:Lessons learned

Colorectal liver metastasis(CRLM) is the major cause of death in patients diagnosed with colorectal cancer. The gold standard treatment of CRLM is surgical rese-ction. Yet, in the past, more than half of these patients were deemed unresectable due to the inadequate future liver remnant(FLR). The introduction of efficient portal vein embolization(PVE) preoperatively allowed more resections of metastasis in CRLM patients by stimulating adequate liver hypertrophy. However, several exp-erimental and clinical studies reported tumor progression after PVE which critically influences the subsequent management of these patients. The underlying path-ophysiological mechanism of tumor progression post-PVE is still not fully understood. In spite of the adverse effects of PVE, it remains a potentially curative procedure in patients who would remain otherwise unresectable because of the insufficient FLR. Currently, the challenge is to halt tumor proliferation following PVE in patients who require this technique. This could potentially be achieved by either attempting to suppress the underlying oncologic stimulus or by inhibiting tumor growth once observed after PVE, without jeopardizing liver regeneration. More research is still required to better identify patients at risk of experiencing tumor growth post-PVE.

Rescue associating liver partition and portal vein ligation for staged hepatectomy after portal embolization: Our experience and literature review

AIM To report a single-center experience in rescue associating liver partition and portal vein ligation for staged hepatectomy(ALPPS), after failure of previous portal embolization. We also performed a literature review.METHODS Between January 2014 and December 2015, every patient who underwent a rescue ALPPS procedure in Toulouse Rangueil University Hospital, France, was included. Every patient included had a project of major hepatectomy and a previous portal vein embolization(PVE) with insufficient future liver remnant to body weight ratio after the procedure. The ALPPS procedure was performed in two steps(ALPPS-1 and ALPPS-2), separated by an interval phase. ALPPS-2 was done within 7 to 9 d after ALPPS-1. To estimate the FLR, a computed tomography scan examination was performed 3 to 6 wk after the PVE procedure and 6 to 8 d after ALPPS-1. A transcystic stent was placed during ALPPS-1 and remained opened duringthe interval phase, in order to avoid biliary complications. Postoperative liver failure was defined using the 50-50 criteria. Postoperative complications were assessed according to the Dindo-Clavien Classification.RESULTS From January 2014 to December 2015, 7 patients underwent a rescue ALPPS procedure. Median FLR before PVE, ALPPS-1 and ALPPS-2 were respectively 263 cc(221-380), 450 cc(372-506), and 660 cc(575-776). Median FLR/BWR before PVE, ALPPS-1 and ALPPS-2 were respectively 0.4%(0.3-0.5), 0.6%(0.5-0.8), and 1%(0.8-1.2). Median volume growth of FLR was 69%(18-92) after PVE, and 45%(36-82) after ALPPS-1. The combination of PVE and ALPPS induced a growth of median initial FLR of +408 cc(254-513), leading to an increase of +149%(68-199). After ALPPS-2, 4 patients had stage Ⅰ-Ⅱ complications. Three patients had more severe complications(one stage Ⅲ, one stage Ⅳ and one death due to bowel perforation). Two patients suffered from postoperative liver failure according to the 50/50 criteria. None of our patients developed any biliary complication during the ALPPS procedure.CONCLUSION Rescue ALPPS may be an alternative after unsuccessful PVE and could allow previously unresectable patients to reach surgery. Biliary drainage seems to reduce biliary complications.

Ruptured angiosarcoma of the liver treated by emergency catheter-directed embolization

Angiosarcoma is a rare primary malignant neoplasm of the liver with a poor prognosis. Here, we report a case of a patient with a ruptured hepatic angiosarcoma which was treated by emergency catheter-directed embolization, followed by leflc-sided hemihepatectomy.