HITS-CLIP analysis of human ALKBH8 reveals interactions with fully processed substrate tRNAs and with specific noncoding RNAs.

Transfer RNAs acquire a large plethora of chemical modifications. Among those, modifications of the anticodon loop play important roles in translational fidelity and tRNA stability. Four human wobble U-containing tRNAs obtain 5-methoxycarbonylmethyluridine (mcm5U34) or 5-methoxycarbonylmethyl-2-thiouridine (mcm5s2U34), which play a role in decoding. This mark involves a cascade of enzymatic activities. The last step is mediated by alkylation repair homolog 8 (ALKBH8). In this study, we performed a transcriptome-wide analysis of the repertoire of ALKBH8 RNA targets. Using a combination of HITS-CLIP and RIP-seq analyses, we uncover ALKBH8-bound RNAs. We show that ALKBH8 targets fully processed and CCA modified tRNAs. Our analyses uncovered the previously known set of wobble U-containing tRNAs. In addition, both our approaches revealed ALKBH8 binding to several other types of noncoding RNAs, in particular C/D box snoRNAs.

Extensive flagellar remodeling during the complex life cycle of Paratrypanosoma, an early-branching trypanosomatid.

Paratrypanosoma confusum is a monoxenous kinetoplastid flagellate that constitutes the most basal branch of the highly diverse parasitic trypanosomatids, which include human pathogens Trypanosoma and Leishmania This makes Paratrypanosoma uniquely informative for the evolution of obligatory parasitism from free-living lifestyle and the evolution of human parasitism in some trypanosomatid lineages. It has typical promastigote morphology but also forms surface-attached haptomonads and amastigotes. Haptomonads form by attachment to a surface via a large bulge at the base of the flagellum, which is then remodeled into a thin attachment pad associated with flagellum shortening. Promastigotes and haptomonads multiply by binary division, and the progeny of a haptomonad can either remain attached or grow a flagellum and resume swimming. Whole genome sequencing and transcriptome profiling, in combination with analysis of the cell ultrastructure, reveal how the cell surface and metabolism are adapted to parasitism and how characteristic cytoskeletal features are conserved. Our data demonstrate that surface attachment by the flagellum and the flagellar pocket, a Leishmania-like flagellum attachment zone, and a Trypanosoma cruzi-like cytostome are ancestral features, while evolution of extant trypanosomatids, including the human parasites, is associated with genome streamlining and diversification of membrane proteins.

Mixed neuroendocrine-non-neuroendocrine carcinoma of gallbladder: case report.

BACKGROUND: Mixed neuroendocrine-non-neuroendocrine tumors (MINEN) of the gallbladder are extremely rare; indeed, the English expert literature reports a mere handful of case reports and case series on this topic. According to the WHO classification of 2010, MINEN are considered to be tumors consisting of two major components, neuroendocrine and non-neuroendocrine, each of which hosts at least 30% of the total cellular population. To date, the etiology and pathogenesis of MINEN have not been precisely determined and the non-specific symptoms generally result in late diagnosis (mainly in the terminal stages of the condition) and contribute to the generally poor prognosis. As far as the management of the disease is concerned, radical surgery plays a crucial role; however, the significance of surgical debulking and biological therapy applying somatostatin analogues has not yet been determined. CASE PRESENTATION: A 56-year-old female was referred to our department for a rapidly progressing tumor in the subhepatic area along with the infiltration of S5 and S6 liver segments. With regard to preoperative findings, the tumor appeared as operable, although, during the surgery, an extensive involvement of the hepatoduodenal ligament by the tumor through the lymph nodes was revealed. Due to acute perioperative bleeding from the necrotic tumor, we decided to perform modified resection. Histologically, the tumor was confirmed as MINEN of gallbladder, where the neuroendocrine component was dominant over the non-neuroendocrine component. Six weeks after the discharge, the patient underwent a follow-up CT revealing large recurrence of the disease. Thereafter, the patient was started on systemic therapy with etoposide and carboplatin in combination with somatostatin analogues. Thirteen months after the surgery, the patient is in good clinical condition, and while a recently performed PET/MRI scan revealed a hepatic lesion and hilar lymphadenopathy in full regression, there was a spread of small peritoneal and pleural metastases. The patient remains in the follow-up care. CONCLUSIONS: The occurrence of mixed neuroendocrine-non-neuroendocrine neoplasms is extremely rare. Radical surgery remains the only potentially effective approach to the cure of this disease. The role of biological therapy and debulking in the management of the disease has not yet been precisely defined. In our experience, both of these methods have the potential to positively influence overall survival rates and the postoperational quality of life of patients.

Lineage-specific activities of a multipotent mitochondrion of trypanosomatid flagellates.

Trypanosomatids are a very diverse group composed of monoxenous and dixenous parasites belonging to the excavate class Kinetoplastea. Here we studied the respiration of five monoxenous species (Blechomonas ayalai, Herpetomonas muscarum, H. samuelpessoai, Leptomonas pyrrhocoris and Sergeia podlipaevi) introduced into culture, each representing a novel yet globally distributed and/or species-rich clade, and compare them with well-studied flagellates Trypanosoma brucei, Phytomonas serpens, Crithidia fasciculata and Leishmania tarentolae. Differences in structure and activities of respiratory chain complexes, respiration and other biochemical parameters recorded under laboratory conditions reveal their substantial diversity, likely a reflection of different host environments. Phylogenetic relationships of the analysed trypanosomatids do not correlate with their biochemical parameters, with the differences within clades by far exceeding those among clades. As the S. podlipaevi canonical respiratory chain complexes have very low activities, we believe that its mitochondrion is utilised for purposes other than oxidative phosphorylation. Hence, the single reticulated mitochondrion of diverse trypanosomatids seems to retain multipotency, with the capacity to activate its individual components based on the host environment.

Unicentric form of Castleman´s disease, pitfalls of diagnosis and surgical treatment.

Background: Castleman´s disease is an extremely rare heterogenous lymphoproliferative pathology with a mostly benign behavior. It is a localized or generalized lymph node enlargement of an unknown aetiology. Unicentric form is typically a slow-growing solitary mass occurring mostly in the mediastinum, abdominal cavity, retroperitoneum, pelvis and neck. Aetiology and pathogenesis of CD is probably diverse, varying in different types of this heterogeneous disease. Materials and Methods: Authors present a review of this issue based on their extensive experience. The aim is to summarize the crucial factors in the management of diagnostics and a surgical treatment of the unicentric form of Castleman´s disease. One of the key issues in the unicentric form is precise preoperative diagnostics and thus choosing the right surgical treatment strategy. Authors highlight pitfalls of the diagnosis and surgical treatment. Results: All histological types such as a hyaline vascular type, plasmacytic type and a mixed type are presented as well as options of surgical and conservative treatment. Differential diagnosis and malignant potential is discussed. Conclusion: Patients with Castleman´s disease should be treated in the high- volume centers, with a great experience in major surgical procedures as well as with preoperative imaging diagnostic techniques. Specialized pathologists and oncologists focusing on this issue are also absolutely necessary to avoid misdiagnosis. Only this complex approach can lead to excellent outcomes in patients with UCD.

Stage-specific requirement for Isa1 and Isa2 proteins in the mitochondrion of Trypanosoma brucei and heterologous rescue by human and Blastocystis orthologues.

IscA/Isa proteins function as alternative scaffolds for the assembly of Fe-S clusters and/or provide iron for their assembly in prokaryotes and eukaryotes. Isa are usually non-essential and in most organisms are confined to the mitochondrion. We have studied the function of TbIsa1 and TbIsa2 in Trypanosoma brucei, where the requirement for both of them to sustain cell growth depends on the life cycle stage. The TbIsa proteins are abundant in the procyclic form, which contains an active organelle. Both proteins are indispensable for growth, as they are required for the assembly of Fe-S clusters in mitochondrial aconitase, fumarase and succinate dehydrogenase. Reactive oxygen species but not iron accumulate in the procyclic mitochondrion upon ablation of the TbIsa proteins, but their depletion does not influence the assembly of Fe-S clusters in cytosolic proteins. In the bloodstream form, which has a downregulated mitochondrion, the TbIsa proteins are non-essential. The Isa2 orthologue of the anaerobic protist Blastocystis partially rescued the growth and enzymatic activities of TbIsa1/2 knock-down. Rescues of single knock-downs as well as heterologous rescues with human Isa orthologues partially recovered the activities of aconitase and fumarase. These results show that the Isa1 and Isa2 proteins of diverse eukaryotes have overlapping functions.

Effects of liver tumor and post-ablation necrosis volume on the result of radiofrequency ablation.

BACKGROUND/AIMS: To find out whether the total tumor mass and post-ablation necrosis volume influence the disease-free survival of patients following radiofrequency ablation (RFA). METHODOLOGY: Fifty nine patients with RFA of primary and secondary tumors were evaluated retrospectively in a four year period. Total liver mass, post-ablation necrosis volume and their ratio were evaluated using computed tomography examination in the relationship with the risk of insufficient tumor ablation and the disease-free patients survival. RESULTS: A complete ablation was performed in 51 patients, non-ablation in 8 (13.6%) patients. Tumor, necrosis volume were 19.2±19.5, 58.7±44.7mL, respectively. The tumor and necrosis mass ratio was 0.39±0.45. The tumor or necroses mass volume or the tumor/necroses mass ratio had no effect on the patients progression-free survival. Patients with a necrosis volume <25mL had a 10-times higher risk of insufficient ablation (OR=9.9; 95% CI=1.9-51.5; p<0.002) and patients with the tumor/necrosis mass ratio >0.4 had a 8-times higher risk of insufficient ablation (OR=7.9; 95% CI=1.4-44.6; p<0.01). CONCLUSIONS: Necrosis volume after RFA and tumor/necrosis mass ratio are the important factors for insufficient ablation but do not have any influence on the patients progression-free survival.

Non-colorectal liver metastases: surgical treatment options.

BACKGROUND/AIMS: Due to different biological characteristics of non-colorectal liver metastasizes (NCLM), surgical treatment, especially it´s long term results, is a topic of discussion. The aim of the study was to evaluate the single center experience with surgical treatment of NCLM. METHODOLOGY: Seventy two patients were prospectively included. The average length of time after the primary surgery was 3.9 years (0-8.5 years). RFA prevailed -50 patients (69.4%), resection presenting 30.6%. Preoperative chemotherapeutical downstaging or portal vein embolization was performed on 12 patients (16.7%). Resectable or radiofrequency ablation (RFA) treatable extrahepatic metastasizes were removed in 26 patients (36.1%). RESULTS: One, three and five years patient survival after the liver resection or RFA was 88.6, 72.5 and 36.9%. The best survival rate was in patients with carcinoid (5 years-100%), breast cancer (5 years-33.8%), renal carcinoma (3 years-44.4% ) and gynecological tumors metastasizes (2 years-72.9%). With regards to long-term survival of patients, we did not find any statistically significant difference between RFA and resection. Patients with extrahepatic metastasizes had worse prognosis (p<0.01). CONCLUSIONS: Liver resection and RFA in NCLM have an unambiguous place in multi-modal curative strategy. The decision for surgical treatment of patients suffering from NCLM, is strictly individual with the aim of achieving qualitative long-term survival.

Prognostic value of the number and volume of liver tumours on portal vein embolization outcomes.

BACKGROUND/AIMS: Portal vein embolization (PVE) extends the resecability of liver tumours.The issue of PVE is an insufficient growth of the liver parenchyma or a tumour progression in some patients. We evaluated the effect of the volume and the number of liver tumours on the effect of PVE. METHODOLOGY: PVE was performed in 40 patients with liver tumours due to an insufficient future remnant liver volume. The number and the volume of the tumours were evaluated and compared with the final PVE effect. RESULTS: In patients without any increase of the liver volume after PVE (n=3) the number and the volume of the tumours before PVE were 2.7±2.1 and 2205.1±2432.7mm3, respectively. In patients with sufficient growth of the liver (n=22) it was 3.8±2.2 (NS) and 1164.9±1392.1mm3 (NS), respectively. In patients with tumour progression (n=11) it was 5.6±2.2 and 6971.4±5189.5mm3, respectively (p<0.04 and p<0.005, respectively). Four patients were treated by radiofrequency ablation only due to worsening of their health state. Patients with >4 foci (OR 4.7) and a tumour volume >400mm3 (OR=13.0) had a higher probability of cancer progression or insufficient growth of the liver tissue. Patients with <6 foci and a tumour volume <3100mm3 had an 87.5% probability of a successful liver hypertrophy after PVE. CONCLUSIONS: The tumour number and volume were crucial for progression of a malignant disease and growth of the liver parenchyma after PVE.

Tumour necrosis factor-alpha stimulates liver regeneration in porcine model of partial portal vein ligation.

BACKGROUND/AIMS: Portal vein ligation (PVL) could multiply the future liver remnant volume (FLRV). Tumor necrosis factor- alpha (TNF-α) is a pleiotropic cytokine that is connected with initial phase of liver regeneration. The aim of this basic pilot study was to accelerate regeneration of liver parenchyma after PVL. The experimental porcine model was developed to be as much compatible as possible with portal vein embolization (PVE) in human medicine. METHODOLOGY: After ligation of portal branches of caudate and right lateral and right medial liver lobes recombinant porcine TNF-α (TNF-α group) or physiological solution (control group) were applied into non-occluded portal vein branches. The biochemical and immunoanalytical parameters were assessed. The compensatory hypertrophy was evaluated by periodic ultrasonography. The histological examination of liver was performed. RESULTS: The acceleration of growth of hypertrophic liver lobes was maximal at the 7th postoperative day in comparison with the control group (p<0.05); nevertheless this stimulating effect was lost at the end of experiment. The important differences in biochemical or histological studied parametres between study groups were not proved. CONCLUSIONS: The achieved acceleration of growth of hypertrophic liver lobes after application of TNF-α confirms the role of studied cytokine in priming of liver regeneration.

Inhibition of transforming growth factor beta-1 augments liver regeneration after partial portal vein ligation in a porcine experimental model.

BACKGROUND/AIMS: TGF-ß1 is a pleiotropic cytokine that is over expressed in terminal phase of liver regeneration. METHODOLOGY: Twenty-four hours after partial portal vein ligation monoclonal antibody against TGF-ß1 (TGF-ß1 group, 7 piglets) or physiological solution (control group, 9 piglets) were applied into the central venous catheter. The biochemical parameters (bilirubin, urea, creatinine, alkaline phosphatase, gamma- glutamyl transferase, cholinesterase, aspartate aminotransferase, alanine aminotransferase and albumin) were assessed. The compensatory hypertrophy of the non-occluded liver lobes was evaluated by periodic ultrasonography during the next fourteen days and by histological examination. RESULTS: The acceleration of growth of the hypertrophic liver lobes was maximal between 3rd and 7th postoperative days in comparison with the control group (p<0.05). No important differences in the biochemical or studied histological parameters were proved. CONCLUSIONS: The present study describes a new usage of monoclonal antibody against TGF-ß1 in large animal experimental model of partial portal vein ligation.

Bevacizumab Does Not Inhibit the Formation of Liver Vessels and Liver Regeneration Following Major Hepatectomy: A Large Animal Model Study.

BACKGROUND/AIM: Patients with unresectable liver colorectal cancer metastases are treated with neoadjuvant chemotherapy often accompanied by biological therapy aimed at reducing the mass of metastases and thus increasing the chances of resectability. Bevacizumab comprises an anti-VEGF (vascular endothelial growth factor) humanized IgG monoclonal antibody that is used for biological therapy purposes. It acts to inhibit angiogenesis, thereby slowing down the growth of metastases. Due to its being administered systematically, bevacizumab also exerts an effect on the surrounding healthy liver parenchyma and potentially limits the process of neovascularization and thus regeneration of the liver. Since the remnant liver volume forms an important factor in postoperative morbidity and mortality following a major hepatectomy, we decided to study the effect of bevacizumab on vascular and biliary microarchitecture in healthy liver parenchyma and its ability to regenerate following major hepatectomy. MATERIALS AND METHODS: We performed an experiment employing a large animal model where a total of 16 piglets were divided into two groups (8 piglets in the control group and 8 piglets in the experimental group with bevacizumab). All the animals were subjected to major hepatectomy and the experimental group was given bevacizumab prior to hepatectomy. All the animals were sacrificed after 4 weeks. We performed biochemical analyses at regular time intervals during the follow-up period. Histological examination of the liver tissue was performed following sacrifice of the animals. RESULTS: No statistical difference was shown between groups in terms of the biochemical and immunohistochemical parameters. The histological examination of the regenerating liver tissue revealed the higher length density of sinusoids in the experimental group. CONCLUSION: Bevacizumab does not act to impair liver regeneration following hepatectomy.

Endosymbiont Capture, a Repeated Process of Endosymbiont Transfer with Replacement in Trypanosomatids Angomonas spp.

Trypanosomatids of the subfamily Strigomonadinae bear permanent intracellular bacterial symbionts acquired by the common ancestor of these flagellates. However, the cospeciation pattern inherent to such relationships was revealed to be broken upon the description of Angomonas ambiguus, which is sister to A. desouzai, but bears an endosymbiont genetically close to that of A. deanei. Based on phylogenetic inferences, it was proposed that the bacterium from A. deanei had been horizontally transferred to A. ambiguus. Here, we sequenced the bacterial genomes from two A. ambiguus isolates, including a new one from Papua New Guinea, and compared them with the published genome of the A. deanei endosymbiont, revealing differences below the interspecific level. Our phylogenetic analyses confirmed that the endosymbionts of A. ambiguus were obtained from A. deanei and, in addition, demonstrated that this occurred more than once. We propose that coinfection of the same blowfly host and the phylogenetic relatedness of the trypanosomatids facilitate such transitions, whereas the drastic difference in the occurrence of the two trypanosomatid species determines the observed direction of this process. This phenomenon is analogous to organelle (mitochondrion/plastid) capture described in multicellular organisms and, thereafter, we name it endosymbiont capture.

Long-term Results of Surgery for Colorectal Liver Metastases in Terms of Primary Tumour Location and Clinical Risk Factors.

BACKGROUND/AIM: The aim of the study was to evaluate the influence of primary tumour location and clinical risk factors for long-term results of surgery for colorectal liver metastases (CLMs). PATIENTS AND METHODS: Overall survival (OS) and recurrence-free survival (RFS) were evaluated in 636 patients. Patients were divided by tumour location (right-/left-sided colorectal cancer: RCRC/LCRC; rectal cancer), and age, gender, number and size of CLMs, type of liver surgery and interval from primary operation were evaluated. RESULTS: One-, 3- and 5-year OS and RFS were independent of primary tumour location (p<0.59). CLM diameter was negatively associated with OS for the whole cohort (p<0.002), and RCRC (p<0.03) and LCRC (p<0.04) groups, as well as for RFS of those with LCRC (p<0.04). CLM number was negatively associated with RFS for the whole cohort (p<0.0001), RCRC (p<0.02), LCRC (p<0.0001) and RC (p<0.02). Radiofrequency ablation and combined procedures led to worse OS for the whole cohort (p<0.03), and to worse RFS for the whole cohort (p<0.0003) and for those with LCRC (p<0.03). A shorter interval between primary colorectal cancer surgery and CLMs procedure was risky for poor OS and RFS of patients with CLMs from RCRC (p<0.05), LCRC (p<0.05) and RC (p<0.02). CONCLUSION: Primary tumour location together with clinical risk factors are important for long-term results of surgery CLMs.

Optimization of the model of abdominal aortic aneurysm--experiment in an animal model.

BACKGROUND: Many studies have been performed in order to model abdominal aortic aneurysm (AAA) in an experimental animal, most commonly in small laboratory animals. In our study, we tried to find the best AAA model in a pig by using various mechanical and enzymatic mechanisms. METHODS: Twenty-two pigs were operated on. We combined 3 mechanisms of creating an AAA, using an intraluminal infusion of porcine pancreatic elastase into the abdominal aortic segment, application of plastic cuff below the renal arteries causing turbulent blood flow, and inserting a patch into the longitudinal aortotomy. RESULTS: We found different results in different groups according to the mechanisms used. In group A, with a combination of the intraluminal elastase infusion and application of a stenosing cuff, AAA developed in all 7 animals (100%). In this group, we also found the largest histological changes in the abdominal aorta samples. CONCLUSION: The use of intraluminal pancreatic elastase infusion, together with increased turbulent flow caused by the stenosing cuff, seems to be the best model of AAA in pigs. This model is suitable for further research in the etiopathology of AAA. In fact, it is the first successful approach to a large-caliber native aneurysm model.

Interleukin-6 augments activation of liver regeneration in porcine model of partial portal vein ligation.

BACKGROUND: Portal vein ligation (PVL) could multiply the future liver remnant volume (FLRV). Interuleukin-6 (IL-6) is a pleiotropic cytokine that is associated with an initial phase of liver regeneration. The aim of this study was to accelerate the regeneration of liver parenchyma after PVL by intraportal cytokine application. MATERIALS AND METHODS: After ligation of portal branches of caudate and right lateral and right medial liver lobes, recombinant porcine IL-6 (IL-6 group) or physiological solution (control group) were applied into non-occluded portal vein branches. The biochemical and immunoanalytical parameters were assessed. The compensatory hypertrophy was evaluated by periodic ultrasonography. The histological examination of liver was performed. RESULTS: The acceleration of growth of hypertrophic liver lobes was maximal at the 7th postoperative day in comparison with the control group (p<0.05), nevertheless, this stimulating effect was lost at the end of the experiment. Important differences in biochemical or histological studied parametres were not proved. CONCLUSION: The presented study describes the use of IL-6 for stimulation of the first phase of liver regeneration. The achieved acceleration of growth of hypertrophic liver lobes after application of IL-6 confirmed the key role of the studied cytokine in priming regenerating liver parenchyma after portal vein ligation.

Intraportal injection of porcine multipotent mesenchymal stromal cells augments liver regeneration after portal vein embolization.

UNLABELLED: Portal vein embolization (PVE) can be used prior to liver surgery to increase the volume of the remaining liver tissue after an extensive resection. However, the application of PVE is limited and new strategies to augment liver regeneration by cellular therapy are promising alternatives. MATERIALS AND METHODS: The influence of syngeneic multipotent mesenchymal stromal cells (MSC) on liver regeneration was analysed after the ligation of the right portal vein branches in a porcine model, closely mimicking the situation of human surgery. Liver regeneration was monitored by ultrasonography, immunohistological analysis and serum biochemistry. RESULTS: The volume of the contra-lateral, non-ligated liver lobe increased in all piglets after portal vein ligation. This hyperplasia occurred earlier and was more pronounced in those piglets receiving MSC infusions as compared to non-treated controls. Biochemical liver function was stable in all pigs. Only solitary transplanted MSC were detected in recipient livers two weeks after the infusion. CONCLUSION: The infusion of porcine MSC into the portal vein in a setting of liver regeneration after surgical resection leads to accelerated and augmented hyperplasia. This effect is most likely due to bystander effects of the transplanted MSC.

The role of RNA adenosine demethylases in the control of gene expression.

RNA modifications are being recognized as an essential factor in gene expression regulation. They play essential roles in germ line development, differentiation and disease. In eukaryotic mRNAs, N6-adenosine methylation (m6A) is the most prevalent internal chemical modification identified to date. The m6A pathway involves factors called writers, readers and erasers. m6A thus offers an interesting concept of dynamic reversible modification with implications in fine-tuning the cellular metabolism. In mammals, FTO and ALKBH5 have been initially identified as m6A erasers. Recently, FTO m6A specificity has been debated as new reports identify FTO targeting N6,2'-O-dimethyladenosine (m6Am). The two adenosine demethylases have diverse roles in the metabolism of mRNAs and their activity is involved in key processes, such as embryogenesis, disease or infection. In this article, we review the current knowledge of their function and mechanisms and discuss the existing contradictions in the field. This article is part of a Special Issue entitled: mRNA modifications in gene expression control edited by Dr. Soller Matthias and Dr. Fray Rupert.

Portal Vein Embolization (PVE) Versus PVE with Haematopoietic Stem Cell Application in Patients with Primarily Non-resectable Colorectal Liver Metastases.

BACKGROUND: Portal vein embolization (PVE) and PVE with autologous mesenchymal stem cell application (PVE-MSC) increases future liver remnant volume (FLRV). The aim of this study was to compare both methods from the aspect of FLRV growth, progression of colorectal liver metastases (CLM), CLM resectability and long-term results. PATIENTS AND METHODS: Fifty-five patients with CLM and insufficient FLRV were included in the study. FLVR growth and CLM volume were evaluated using computed tomography. Liver resection was performed in patients with FLVR >30% of total liver volume. RESULTS: In the PVE (N=27) group, FLRV growth was observed in 23 patients (85.2%) and in 100% of patients in the PVE-MSC (N=28) group (p<0.05). The rapidity of FLRV and CLM growth did not differ between groups. R0 resection was performed in 14 (51.8%) and 24 (85.7%) patients from the PVE and PVE-MSC (p<0.02) groups, respectively. The 3-year overall and progression-free survival rates were 85.75% and 9.3% in the PVE group and 68.7% and 17.1% in the PVE-MSC group, respectively (p<0.67 and p<0.84, respectively). CONCLUSION: PVE-MSC allows for more effective growth of FLRV and resectability of CLM compared to PVE. The two methods do not differ in their long-term results.

Repeated procedures for colorectal liver metastases.

BACKGROUND/AIMS: After primary liver surgery a recurrence of colorectal liver metastases (CRLM) occurs in 45-80% of patients. Without the possibility of further surgical treatment, most of these patients die within 1 year. The aim of this study was to evaluate the long-term results of repeated liver procedures for recurrent CRLM. METHODOLOGY: The authors operated on a total of 151 patients with CRLM from January 1, 2000 to November 1, 2005. Repeated procedures were performed on 24 patients in the interval 6-37 months after primary liver surgery. A total of 51 procedures were performed. Long-term results were compared with the group of patients (N = 127) where only one type of liver procedure was performed. RESULTS: 30-day postoperative mortality (N = 24) was zero. 83.3%, 64.8% and 34.3% of patients survived 1.2 and 3 years after the repeated procedures. Disease-free interval (DFI) was 32.1%, 5.3% and 0% for 1, 2 and 3 years. 30-day postoperative mortality (N = 127) was 0.8%. 76.6%, 51.9%, 31.9% survived 1, 2 and 3 years after the liver procedures (p < 0.08). DFI in this group of patients for 1, 2 and 3 years was 57.9%, 35.1% and 17.7% (p < 0.0001). CONCLUSIONS: Repeated liver procedures are fully indicated. They significantly prolong the life of patients with CRLM recurrence.