Hierarchical organization of cortical and thalamic connectivity.

The mammalian cortex is a laminar structure containing many areas and cell types that are densely interconnected in complex ways, and for which generalizable principles of organization remain mostly unknown. Here we describe a major expansion of the Allen Mouse Brain Connectivity Atlas resource1, involving around a thousand new tracer experiments in the cortex and its main satellite structure, the thalamus. We used Cre driver lines (mice expressing Cre recombinase) to comprehensively and selectively label brain-wide connections by layer and class of projection neuron. Through observations of axon termination patterns, we have derived a set of generalized anatomical rules to describe corticocortical, thalamocortical and corticothalamic projections. We have built a model to assign connection patterns between areas as either feedforward or feedback, and generated testable predictions of hierarchical positions for individual cortical and thalamic areas and for cortical network modules. Our results show that cell-class-specific connections are organized in a shallow hierarchy within the mouse corticothalamic network.

Hepatitis B transmission/reactivation associated with Hepatitis B core antibody and Hepatitis C nucleic acid testing positive organs: A report from the Organ Procurement and Transplantation Network Disease Transmission Advisory Committee.

BACKGROUND: Better access to direct-acting antiviral (DAA) therapy has broadened the utilization of hepatitis C virus (HCV) nucleic acid testing (NAT) positive organs with excellent outcomes. However, DAA therapy has been associated with hepatitis B virus (HBV) reactivation. AIM: To determine the risk of HBV transmission or reactivation with utilization of HBV core antibody positive (HBcAb+) and HCV NAT positive (HCV+) organs, which presumably required DAA therapy. METHODS: The number of HBcAb+ donors with delineated HCV NAT status was obtained from the Organ Procurement and Transplantation Network (OPTN) database. The number of unexpected HBV infections from transplanted organs adjudicated as "proven" or "probable" transmission was obtained from the OPTN Ad Hoc Disease Transmission Advisory Committee database. A chart review of the donors of "proven" or "probable" cases was conducted. RESULTS: From January 1, 2016, to December 31, 2021, 7735 organs were procured from 3767 HBcAb+ donors and transplanted into 7469 recipients; 545 (14.5%) donors were also HCV+. HBV transmission or reactivation occurred in seven recipients. The rate is not significantly different between recipients of HCV+ (0.18%, 2/1115) and the HCV NAT negative (HCV-) organs (0.08%, 5/6354) (p = 0.28) or between recipients of HCV+ and HCV- livers as well as non-liver organs. HBV transmission or reactivation occurred within a median of 319 (range, 41-1117) days post-transplant in the setting of missing, inadequate, or truncated prophylaxis. CONCLUSION: HBV reactivation associated with DAA therapy for HBcAb+ HCV+ organs is less frequent than reported in the non-transplant population, possibly due to the common use of HBV prophylaxis in the at-risk transplant population.

Transplant of organs from donors with positive SARS-CoV-2 nucleic acid testing: A report from the organ procurement and transplantation network ad hoc disease transmission advisory committee.

BACKGROUND: Decisions to transplant organs from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid test-positive (NAT+) donors must balance risk of donor-derived transmission events (DDTE) with the scarcity of available organs. METHODS: Organ Procurement and Transplantation Network (OPTN) data were used to compare organ utilization and recipient outcomes between SARS-CoV-2 NAT+ and NAT- donors. NAT+ was defined by either a positive upper or lower respiratory tract (LRT) sample within 21 days of procurement. Potential DDTE were adjudicated by OPTN Disease Transmission Advisory Committee. RESULTS: From May 27, 2021 (date of OTPN policy for required LRT testing of lung donors) to January 31, 2022, organs were recovered from 617 NAT+ donors from all OPTN regions and 53 of 57 (93%) organ procurement organizations. NAT+ donors were younger and had higher organ quality scores for kidney and liver. Organ utilization was lower for NAT+ donors compared to NAT- donors. A total of 1241 organs (776 kidneys, 316 livers, 106 hearts, 22 lungs, and 21 other) were transplanted from 514 NAT+ donors compared to 21 946 organs from 8853 NAT- donors. Medical urgency was lower for recipients of NAT+ liver and heart transplants. The median waitlist time was longer for liver recipients of NAT+ donors. The match run sequence number for final acceptor was higher for NAT+ donors for all organ types. Outcomes for hospital length of stay, 30-day mortality, and 30-day graft loss were similar for all organ types. No SARS-CoV-2 DDTE occurred in this interval. CONCLUSIONS: Transplantation of SARS-CoV-2 NAT+ donor organs appears safe for short-term outcomes of death and graft loss and ameliorates the organ shortage. Further study is required to assure comparable longer term outcomes.

Early United States experience with liver donation after circulatory determination of death using thoraco-abdominal normothermic regional perfusion: A multi-institutional observational study.

Mortality on the liver waitlist remains unacceptably high. Donation after circulatory determination of death (DCD) donors are considered marginal but are a potentially underutilized resource. Thoraco-abdominal normothermic perfusion (TA-NRP) in DCD donors might result in higher quality livers and offset waitlist mortality. We retrospectively reviewed outcomes of the first 13 livers transplanted from TA-NRP donors in the US. Nine centers transplanted livers from eight organ procurement organizations. Median donor age was 25 years; median agonal phase was 13 minutes. Median recipient age was 60 years; median lab MELD score was 21. Three patients (23%) met early allograft dysfunction (EAD) criteria. Three received simultaneous liver-kidney transplants; neither had EAD nor delayed renal allograft function. One recipient died 186 days post-transplant from sepsis but had normal presepsis liver function. One patient developed a biliary anastomotic stricture, managed endoscopically; no recipient developed clinical evidence of ischemic cholangiopathy (IC). Twelve of 13 (92%) patients are alive with good liver function at 439 days median follow-up; one patient has extrahepatic recurrent HCC. TA-NRP DCD livers in these recipients all functioned well, particularly with respect to IC, and provide a valuable option to decrease deaths on the waiting list.

A mesoscale connectome of the mouse brain.

Comprehensive knowledge of the brain's wiring diagram is fundamental for understanding how the nervous system processes information at both local and global scales. However, with the singular exception of the C. elegans microscale connectome, there are no complete connectivity data sets in other species. Here we report a brain-wide, cellular-level, mesoscale connectome for the mouse. The Allen Mouse Brain Connectivity Atlas uses enhanced green fluorescent protein (EGFP)-expressing adeno-associated viral vectors to trace axonal projections from defined regions and cell types, and high-throughput serial two-photon tomography to image the EGFP-labelled axons throughout the brain. This systematic and standardized approach allows spatial registration of individual experiments into a common three dimensional (3D) reference space, resulting in a whole-brain connectivity matrix. A computational model yields insights into connectional strength distribution, symmetry and other network properties. Virtual tractography illustrates 3D topography among interconnected regions. Cortico-thalamic pathway analysis demonstrates segregation and integration of parallel pathways. The Allen Mouse Brain Connectivity Atlas is a freely available, foundational resource for structural and functional investigations into the neural circuits that support behavioural and cognitive processes in health and disease.

Building the multidisciplinary team for management of patients with hepatocellular carcinoma.

Optimal care of the patient with hepatocellular carcinoma (HCC) necessitates the involvement of multiple providers. Because the patient with HCC often carries 2 conditions with competing mortality risks (cancer and underlying cirrhosis), no single provider is equipped to deal with all of these patients' needs adequately. Multidisciplinary teams (MDTs) have evolved to facilitate care coordination, reassessments of clinical course, and nimble changes in treatment plans required for this complex group of patients. Providers or sites that elect to manage patients with HCC thus are increasingly aware of the need to build their own MDT or communicate with an established one. The availability of new communication technologies, such as teleconferencing or teleconsultation, offers the possibility of MDT expansion into underserved or rural areas, as well as areas such as correctional facilities. Although the availability of resources for HCC patient care varies from site to site, construction of an MDT is possible in a wide spectrum of clinical practices, and this article suggests a blueprint for assembly of such collaboration. Research strategies are needed to explain how MDTs improve clinical outcomes so that MDTs themselves can be improved.

US Liver Transplant Outcomes After Normothermic Regional Perfusion vs Standard Super Rapid Recovery.

Importance: Normothermic regional perfusion (NRP) is an emerging recovery modality for transplantable allografts from controlled donation after circulatory death (cDCD) donors. In the US, only 11.4% of liver recipients who are transplanted from a deceased donor receive a cDCD liver. NRP has the potential to safely expand the US donor pool with improved transplant outcomes as compared with standard super rapid recovery (SRR). Objective: To assess outcomes of US liver transplants using controlled donation after circulatory death livers recovered with normothermic regional perfusion vs standard super rapid recovery. Design, Setting, and Participants: This was a retrospective, observational cohort study comparing liver transplant outcomes from cDCD donors recovered by NRP vs SRR. Outcomes of cDCD liver transplant from January 2017 to May 2023 were collated from 17 US transplant centers and included livers recovered by SRR and NRP (thoracoabdominal NRP [TA-NRP] and abdominal NRP [A-NRP]). Seven transplant centers used NRP, allowing for liver allografts to be transplanted at 17 centers; 10 centers imported livers recovered via NRP from other centers. Exposures: cDCD livers were recovered by either NRP or SRR. Main Outcomes and Measures: The primary outcome was ischemic cholangiopathy (IC). Secondary end points included primary nonfunction (PNF), early allograft dysfunction (EAD), biliary anastomotic strictures, posttransplant length of stay (LOS), and patient and graft survival. Results: A total of 242 cDCD livers were included in this study: 136 recovered by SRR and 106 recovered by NRP (TA-NRP, 79 and A-NRP, 27). Median (IQR) NRP and SRR donor age was 30.5 (22-44) years and 36 (27-49) years, respectively. Median (IQR) posttransplant LOS was significantly shorter in the NRP cohort (7 [5-11] days vs 10 [7-16] days; P < .001). PNF occurred only in the SRR allografts group (n = 2). EAD was more common in the SRR cohort (123 of 136 [56.1%] vs 77 of 106 [36.4%]; P = .007). Biliary anastomotic strictures were increased 2.8-fold in SRR recipients (7 of 105 [6.7%] vs 30 of 134 [22.4%]; P = .001). Only SRR recipients had IC (0 vs 12 of 133 [9.0%]; P = .002); IC-free survival by Kaplan-Meier was significantly improved in NRP recipients. Patient and graft survival were comparable between cohorts. Conclusion and Relevance: There was comparable patient and graft survival in liver transplant recipients of cDCD donors recovered by NRP vs SRR, with reduced rates of IC, biliary complications, and EAD in NRP recipients. The feasibility of A-NRP and TA-NRP implementation across multiple US transplant centers supports increasing adoption of NRP to improve organ use, access to transplant, and risk of wait-list mortality.

Multivariate analysis of prognostic factors for survival following doxorubicin-eluting bead transarterial chemoembolization for hepatocellular carcinoma.

PURPOSE: To identify prognostic factors for survival in patients with hepatocellular carcinoma (HCC) treated with transarterial chemoembolization with doxorubicin-eluting beads (DEBs). MATERIALS AND METHODS: In a retrospective, single-center analysis, tumor- and patient-related factors were recorded for univariate and multivariate analyses via Kaplan-Meier and Cox regression. Infiltrative HCC phenotype and portal vein invasion (PVI) were correlated, and patients with either or both were classified as having radiographically advanced (RAdv) HCC. The primary endpoint was overall survival, which was calculated from the time of first DEB chemoembolization procedure. RESULTS: A total of 168 patients underwent 248 procedures, of which 215 (86.7%) were outpatient procedures. Mean length of stay was 0.33 days, and 25 patients (10.1%) were readmitted within 30 days. A total of 33 patients underwent liver transplantation and were excluded from survival analyses. A total of 130 had cirrhosis; 62, 50, and 18 had Child class A, B, and C disease, respectively. Forty-one patients had infiltrative HCC phenotype, 28 of whom also had PVI. Multivariate analysis of survival in all patients showed α-fetoprotein (AFP), performance status (PS), RAdv HCC, Child classification, albumin level, and ascites to predict survival. In patients without RAdv HCC, AFP, PS, Child classification, albumin level, and International Normalized Ratio were independent predictors. Increased bilirubin level was not an independent risk factor for death. CONCLUSIONS: Independent prognostic factors in patients with HCC undergoing DEB chemoembolization have been identified. Increased bilirubin level was not an independent risk factor. These data can be used in HCC patient selection and counseling for DEB chemoembolization.

Signature morphoelectric properties of diverse GABAergic interneurons in the human neocortex.

Human cortex transcriptomic studies have revealed a hierarchical organization of γ-aminobutyric acid-producing (GABAergic) neurons from subclasses to a high diversity of more granular types. Rapid GABAergic neuron viral genetic labeling plus Patch-seq (patch-clamp electrophysiology plus single-cell RNA sequencing) sampling in human brain slices was used to reliably target and analyze GABAergic neuron subclasses and individual transcriptomic types. This characterization elucidated transitions between PVALB and SST subclasses, revealed morphological heterogeneity within an abundant transcriptomic type, identified multiple spatially distinct types of the primate-specialized double bouquet cells (DBCs), and shed light on cellular differences between homologous mouse and human neocortical GABAergic neuron types. These results highlight the importance of multimodal phenotypic characterization for refinement of emerging transcriptomic cell type taxonomies and for understanding conserved and specialized cellular properties of human brain cell types.

A whole-brain monosynaptic input connectome to neuron classes in mouse visual cortex.

Identification of structural connections between neurons is a prerequisite to understanding brain function. Here we developed a pipeline to systematically map brain-wide monosynaptic input connections to genetically defined neuronal populations using an optimized rabies tracing system. We used mouse visual cortex as the exemplar system and revealed quantitative target-specific, layer-specific and cell-class-specific differences in its presynaptic connectomes. The retrograde connectivity indicates the presence of ventral and dorsal visual streams and further reveals topographically organized and continuously varying subnetworks mediated by different higher visual areas. The visual cortex hierarchy can be derived from intracortical feedforward and feedback pathways mediated by upper-layer and lower-layer input neurons. We also identify a new role for layer 6 neurons in mediating reciprocal interhemispheric connections. This study expands our knowledge of the visual system connectomes and demonstrates that the pipeline can be scaled up to dissect connectivity of different cell populations across the mouse brain.

Embolization of hepatocellular carcinoma with drug-eluting beads: doxorubicin tissue concentration and distribution in patient liver explants.

BACKGROUND & AIMS: To follow the local tissue delivery of doxorubicin in HCC explants from patients embolized with drug-eluting beads and to compare it with histologic modifications. METHODS: Six patients with HCC underwent chemoembolization with doxorubicin-eluting beads (caliber 100-300 µm, dose 75-150 mg) followed by liver transplantation at different time points (8 h to 36 days). On sections of the explanted liver, the tissue concentration of doxorubicin was determined radially around bead-occluded vessels with microspectrofluorimetry. The intra/peritumoral location of the beads and the modifications of the surrounding tissue were determined on an adjacent hematein-eosin-saffron-stained section and compared to drug measurements. RESULTS: Doxorubicin was detected in the tissue surrounding the beads at all times of explantation. The drug impregnates an area of at least 1.2 mm in diameter around the occluded vessel. The tissue concentration of drug ranges from 5 µM at 8 h to 0.65 µM at 1 month. In patient transplanted at 8 h, no major tissue modification was observed and we found 42% of the beads occluding intratumoral vessels. Drug concentration was not different around intratumoral and peritumoral occluded vessels. After 9-14 days, necrosis was present around 37% of vessels and at 32-36 days, around 40% of vessels. Necrotic tissue was associated with a deeper penetration and a higher concentration of the drug than non necrotized areas, though statistically significant only at 32-36 days. CONCLUSIONS: Doxorubicin-eluting beads provide a sustained delivery of drug for a period of 1 month and local tissue concentrations above cytotoxic threshold in HCC-bearing livers.

Schnurri mediates Dpp-dependent repression of brinker transcription.

Signalling by Decapentaplegic (Dpp), a member of the TGFbeta superfamily of signalling molecules, controls many aspects of Drosophila development by activating and repressing target genes. Several essential components of the Dpp signalling pathway have been identified, including the Dpp receptors Punt and Thick veins (Tkv) as well as the cytoplasmic mediators Mad and Medea. For target genes to be activated, Dpp signalling must suppress transcription of a repressor encoded by the brinker (brk) gene. Here we show that Schnurri (Shn), a large zinc-finger protein, is essential for Dpp-mediated repression of brk transcription; in contrast, Shn is not required for target-gene activation. Thus, the Dpp signalling pathway bifurcates, downstream of the signal-mediating SMAD proteins, into a Shn-dependent pathway leading to brk repression and a Shn-independent pathway leading to gene activation. The existence of several Shn-like proteins in vertebrates and the observation that Brk functions in BMP signalling in Xenopus indicates that a similar regulatory cascade may be conserved in higher organisms.

Primary intestinal epithelial cells selectively transfer R5 HIV-1 to CCR5+ cells.

The upper gastrointestinal tract is a principal route of HIV-1 entry in vertical transmission and after oral-genital contact. The phenotype of the newly acquired virus is predominantly R5 (CCR5-tropic) and not X4 (CXCR4-tropic), although both R5 and X4 viruses are frequently inoculated onto the mucosa. Here we show that primary intestinal (jejunal) epithelial cells express galactosylceramide, an alternative primary receptor for HIV-1, and CCR5 but not CXCR4. Moreover, we show that intestinal epithelial cells transfer R5, but not X4, viruses to CCR5+ indicator cells, which can efficiently replicate and amplify virus expression. Transfer was remarkably efficient and was not inhibited by the fusion blocker T-20, but was substantially reduced by colchicine and low (4 degrees C) temperature, suggesting endocytotic uptake and microtubule-dependent transcytosis of HIV-1. Our finding that CCR5+ intestinal epithelial cells select and transfer exclusively R5 viruses indicates a mechanism for the selective transmission of R5 HIV-1 in primary infection acquired through the upper gastrointestinal tract.

A prion protein epitope selective for the pathologically misfolded conformation.

Conformational conversion of proteins in disease is likely to be accompanied by molecular surface exposure of previously sequestered amino-acid side chains. We found that induction of beta-sheet structures in recombinant prion proteins is associated with increased solvent accessibility of tyrosine. Antibodies directed against the prion protein repeat motif, tyrosine-tyrosine-arginine, recognize the pathological isoform of the prion protein but not the normal cellular isoform, as assessed by immunoprecipitation, plate capture immunoassay and flow cytometry. Antibody binding to the pathological epitope is saturable and specific, and can be created in vitro by partial denaturation of normal brain prion protein. Conformation-selective exposure of Tyr-Tyr-Arg provides a probe for the distribution and structure of pathologically misfolded prion protein, and may lead to new diagnostics and therapeutics for prion diseases.

[Neurological complications attributable to lithium: An update]. / Complications neurologiques imputables au lithium : mise au point.

Lithium intoxication may induce neurological complications, initially characterised by a conscience alteration and an encephalopathy clinical picture with a risk of death or sever long-term consequences. With an occurrence sometimes atypical and possibly without initial hyperlitemia, the diagnosis delay of these complications might be important. Moreover, no specific guidelines focused on these complications are available. The aim of this article is to propose an update on diagnosis and treatment of neurological complications attributable to lithium, as encephalopathy.

Impact of Sarcopenia, BMI, and Inflammatory Biomarkers on Survival in Advanced Hepatocellular Carcinoma Treated With Anti-PD-1 Antibody.

BACKGROUND: Sarcopenia and inflammation are independently associated with worse survival in cancer patients. This study aims to determine the impact of sarcopenia, body mass index (BMI), and inflammatory biomarkers on survival in advanced hepatocellular carcinoma (HCC) patients treated with anti-PD-1 antibody-based immunotherapy. METHODS: A retrospective review of advanced HCC patients treated with immunotherapy at Winship Cancer Institute between 2015 and 2019 was performed. Baseline computed tomography and magnetic resonance images were collected at mid-L3 level, assessed for skeletal muscle density using SliceOmatic (TomoVision, version 5.0) and converted to skeletal muscle index (SMI) by dividing it by height (m2). Sex-specific sarcopenia was defined by the median value of SMI. The optimal cut for continuous inflammation biomarker was determined by bias-adjusted log-rank test. Overall survival (OS) was set as primary outcome and Cox proportional hazard model was used for association with survival. RESULTS: A total of 57 patients were included; 77.2% male, 52.6% Caucasian, 58.5% Eastern Cooperative Oncology Group performance status 0-1, 80.7% Child Pugh A. Treatment was second line and beyond in 71.9% of patients. The median follow-up time was 6 months. Sarcopenia cut-off for males and females was SMI of 43 and 39, respectively. 49.1% of patients had sarcopenia. Median OS was 5 versus 14.3 months in sarcopenic versus nonsarcopenic patients (Log-rank P=0.054). Median OS was 5 and 17.5 months in patients with BMI <25 and BMI ≥25, respectively (Log-rank P=0.034). Median OS was 3.6 and 14.3 months for patients with neutrophil-to-lymphocyte ratio (NLR) ≥5.15 versus NLR <5.15 (Log-rank P<0.001). In multivariable Cox regression model, higher baseline NLR was associated with worse OS (hazard ratio [HR]: 4.17, 95% confidence interval [CI]: 1.52-11.39, P=0.005). Sex-specific sarcopenia showed a trend of worse OS (HR: 1.71, 95% CI: 0.73-4.00, P=0.215) but was not statistically significant. BMI<25 was associated with worse OS (HR: 2.28, 95% CI: 0.92-5.65, P=0.076). In the association with progression free survival, neither baseline BMI nor sex-specific sarcopenia showed statistical significance. CONCLUSION: After controlling for baseline Child Pugh score and NLR, sex-specific sarcopenia does not predict OS. Baseline BMI and NLR together may predict OS in advanced HCC patients treated with anti-PD-1 antibody.

Evaluation of Medium-Term Efficacy of Y90 Radiation Segmentectomy vs Percutaneous Microwave Ablation in Patients with Solitary Surgically Unresectable < 4 cm Hepatocellular Carcinoma: A Propensity Score Matched Study.

OBJECTIVE: To evaluate the efficacy and safety of Y90 radiation segmentectomy (RS) vs. percutaneous microwave ablation (MWA) in patients with solitary HCC ≤ 4 cm. METHODS: From 2014 to 2017, 68 consecutive treatment naïve patients were included (34 per treatment arm). Chi-square and t-test were used to evaluate differences in baseline demographics between groups. Objective response was evaluated using mRECIST and toxicity using CTCAE. Overall survival (OS) and progression free survival (PFS) in the targeted tumor and the remainder of liver from initial treatment was calculated using Kaplan-Meier estimation. Propensity score matching was then performed with n = 24 patients matched in each group. Similar outcome analysis was then pre-formed. RESULTS: In the overall study population, both groups had similar baseline characteristics with the exception of larger lesions in the RS group. There was no difference in toxicity, objective tumor response, OS and non-target liver PFS between the MWA and RS group (p's > 0.05). In the matched cohort, the objective tumor response was 82.6% in MWA vs. 90.9%% in RS (p = 0.548). The mean OS in the MWA group (44.3 months) vs RS (59.0 months; p = 0.203). The targeted tumor mean PFS for the MWA groups was 38.6 months vs. 57.8 months in RS group (p = 0.005). There was no difference overall PFS and toxicity between the 2 matched groups. CONCLUSIONS: Our data suggest Y90 RS achieves similar tumor response and OS with a similar safety compared to MWA in the management of HCC lesions ≤ 4 cm. Additionally, targeted tumor PFS appears to be prolonged in the RS group with similar non-target liver PFS between RS and MWA group.

Clinical outcomes of rare hepatocellular carcinoma variants compared to pure hepatocellular carcinoma.

BACKGROUND: HCC variants are rare primary hepatic tumors. The aim of this study is to compare clinical characteristics and outcomes of HCC variants with pure HCC. METHODS: Patients diagnosed between 2004 and 2013 with ICD-O-3 8180/3 and 8170/3-8175/3 were identified from the National Cancer Database. Univariate and multivariate survival analyses were conducted to analyze the association between histology and overall survival (OS). RESULTS: 80,280 patients were identified; pure HCC 78,461 (97.7%), fibrolamellar (FLHCC) 310 (0.4%), scirrhous 161 (0.2%), spindle cell 72 (0.1%), clear cell 487 (0.6%), pleomorphic 23 (0.0%), and combined HCC and cholangiocarcinoma (mixed HCC) 766 (1.0%). 76.7% were male and 72% Caucasian. Liver transplant was performed in 10.1% of pure HCC, 14.5% of mixed HCC, 16.2% of scirrhous, 6.9% of spindle cell, 8.8% of clear cell, 8.7% of pleomorphic, and 3.2% of FLHCC (p<0.001). Pure HCC (10.6%) underwent surgical resection without transplant less often than variants except for scirrhous (9.9%) (p<0.001). More than a third of patients in each histological type received chemotherapy. FLHCC had the best 5-year OS (38.7%), spindle cell and pleomorphic had the worst (9.6% and 13.0%). In multivariate analysis stratified by histology variants, chemotherapy was associated with improved OS in all histologies except for scirrhous and pleomorphic HCC. CONCLUSION: HCC variants underwent surgical resection more often than pure HCC. FLHCC had the best 5-year OS. Liver transplant was commonly performed in HCC variants.