Integrative genomic analyses of European intrahepatic cholangiocarcinoma: Novel ROS1 fusion gene and PBX1 as prognostic marker

BACKGROUND

Cholangiocarcinoma (CCA) is a fatal cancer of the bile duct with a poor prognosis owing to limited therapeutic options. The incidence of intrahepatic CCA (iCCA) is increasing worldwide, and its molecular basis is emerging. Environmental factors may contribute to regional differences in the mutation spectrum of European patients with iCCA, which are underrepresented in systematic genomic and transcriptomic studies of the disease.

METHODS

We describe an integrated whole-exome sequencing and transcriptomic study of 37 iCCAs patients in Germany.

RESULTS

We observed as most frequently mutated genes ARID1A (14%), IDH1, BAP1, TP53, KRAS, and ATM in 8% of patients. We identified FGFR2::BICC1 fusions in two tumours, and FGFR2::KCTD1 and TMEM106B::ROS1 as novel fusions with potential therapeutic implications in iCCA and confirmed oncogenic properties of TMEM106B::ROS1 in vitro. Using a data integration framework, we identified PBX1 as a novel central regulatory gene in iCCA. We performed extended screening by targeted sequencing of an additional 40 CCAs. In the joint analysis, IDH1 (13%), BAP1 (10%), TP53 (9%), KRAS (7%), ARID1A (7%), NF1 (5%), and ATM (5%) were the most frequently mutated genes, and we found PBX1 to show copy gain in 20% of the tumours. According to other studies, amplifications of PBX1 tend to occur in European iCCAs in contrast to liver fluke-associated Asian iCCAs.

CONCLUSIONS

By analyzing an additional European cohort of iCCA patients, we found that PBX1 protein expression was a marker of poor prognosis. Overall, our findings provide insight into key molecular alterations in iCCA, reveal new targetable fusion genes, and suggest that PBX1 is a novel modulator of this disease.

[The German Transplant Registry - An Analysis of Legacy Data 2006-2016]

INTRODUCTION

In 2018, medical transplant data from three institutions were merged to create a German transplant registry. Since June 2021, access to data of the registry has been available. It was planned to analyze the registry data in order to compare special allocation rules with regular allocation for heart, liver, lung, and kidney transplantation. Our approach led to a quality analysis of the registry.

METHODS

Upon request, legacy data (2006-2016) of the registry was provided, divided into 61 elements. From these elements, the user had to compile the required dataset. Data checks were performed for completeness, correct allocation of information, and consistency among different sources. Software used for these tasks included R, SQL, and Excel.

RESULTS

The initial elements ("waiting list" elements) of the four types of transplantations contained data from a total of 80,259 originally listed patients. However, these patients were only partially present in other elements resulting in complete datasets reflecting waiting time in only 23%, 30%, 50%, and 96%, and for post-transplantation outcomes in 14%, 11%, 38%, and 13% (heart, liver, lung, and kidney transplantation, respectively). The linking of urgency information with clinical data was successful in only a small proportion, with only 6% for heart transplantation. Incorrect and thus implausible allocations in the case of special allocation rules indicated incorrect entries in the registry. Data from different data providers were inconsistent.

DISCUSSION

The incompleteness and incorrect data allocation raise doubts about the reliability of scientific studies based on the transplant registry. The complex structure also hinders the compilation of a reliable dataset, which is uncommon internationally. New data (acquisition since 2017) has only been available since December 2023.

CONCLUSION

The transplant registry urgently needs restructuring. Competent clinical data management, involving transplant medical expertise, and continuous quality controls are essential in this process.

Transjugular Portosystemic Stent Shunt: Impact of Right Atrial Pressure on Portal Venous Hemodynamics Within the First Week

Purpose

Porto-systemic pressure gradient is used to prognosticate rebleeding and resolution of ascites after TIPS. This study investigates the reliability of portal pressure characteristics as quantified immediately after TIPS placement and at short-term control.

Patients and Methods

Portal venous pressure (PVP) and right atrial pressure (RAP) were prospectively obtained before and after TIPS as well as ≥ 48 h after TIPS procedure. Porto-systemic pressure gradients (PSG) and pressure changes were calculated. A multivariate regression analysis was performed to predict portal hemodynamics at short-term control.

Results

The study included 124 consecutive patients. Indications for TIPS were refractory ascites, variceal bleeding or combinations of both. Pre- and post-interventional PSG yielded 16.4 ± 5.3 mmHg and 5.9 ± 2.7 mmHg, respectively. At that time, 105/124 patients (84.7%) met the target (PSG ≤ 8 mmHg). After 4 days (median), PSG was 8.5 ± 3.5 mmHg and only 66 patients (53%) met that target. In patients exceeding the target PSG at follow-up, PVP was significantly higher and RAP was lower resulting in the increased PSG. The highly variable changes of RAP were the main contributor to different pressure gradients. In the multivariate regression analysis, PVP and RAP immediately after TIPS were predictors for PSG at short-term control with moderately predictive capacity (AUC = 0.75).

Conclusion

Besides the reduction of portal vein pressure, the highly variable right atrial pressure was the main contributor to different pressure gradients. Thus, immediate post-TIPS measurements do not reliably predict portal hemodynamics during follow-up. These findings need to be further investigated with respect to the corresponding clinical course of the patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00270-021-03003-z.

Liver transplantation and BCLC classification: Limitations impede optimum treatment

BACKGROUND

The Barcelona Clinic Liver Cancer (BCLC) system has been endorsed by international guidelines as a staging algorithm of hepatocellular carcinoma. This analysis was performed to assess the outcome of liver transplantation in patients treated against the BCLC recommendations.

METHODS

The data of 198 patients who underwent liver transplantation for hepatocellular carcinoma were extracted from a prospectively maintained database to classify the patients according to the BCLC system.

RESULTS

BCLC staging was as follows: 0, n = 5; A, n = 77; B, n = 41; C, n = 53; and D, n = 22. Accordingly, liver transplantation was performed in the majority of patients against BCLC recommendations. Surgery (n = 16), radiofrequency ablation (n = 15) and transarterial chemoembolization (n = 151) preceded liver transplantation in 182 patients. Sixteen patients were transplanted without pretreatment. The1-, 5- and 10-year survival rates were 83.8%, 62.4% and 45.9%, and 1-, 5-, and 10-year recurrence rates were 7.7%, 22.7% and 26.7%. The BCLC classification did neither impact survival (P = 0.796) nor recurrence (P = 0.693). In the Cox analysis, RECIST tumor progression and initial alpha fetoprotein were independent predictors of outcome.

CONCLUSIONS

Neither the oncological nor the functional stratification imposed by the BCLC system was of importance for outcome. Lack of flexibility and disregard of biological parameters hamper its clinical applicability in liver transplantation.

Microvascular invasion of hepatocellular carcinoma predicts microvascular invasion of its recurrence: potential implications for salvage liver transplantation?

Background

Microvascular invasion (MVI) can only be assessed on a full surgical specimen. We aimed at evaluating, whether the histology of the primary tumor is predictive of MVI in a hepatocellular carcinoma (HCC) recurrence.

Methods

Patients, who underwent liver resection or orthotopic liver transplantation (OLT) for recurrent HCC from January 2001 until June 2018 were eligible for this retrospective analysis. Resected specimens were evaluated for HCC subtype/morphology, vessels encapsulating tumor clusters (VETC)-pattern and MVI. Dichotomous parameters were analyzed using χ²-test and ϕ-values, with P values <0.05 being considered significant.

Results

Of 230 HCC recurrences, 37 (16.1%) underwent repeated liver resection (n=22) or OLT (n=15). Of these, 67.6% initially exceeded the Milan criteria. MVI correlated Milan criteria (P=0.005), tumor size (P=0.015) and VETC-pattern (P=0.034) in the primary specimen. The recurrences shared many features of the primary HCC such as tumor grade (P=0.002), VETC-pattern (P=0.035), and MVI (P=0.046). In recurrences, however, only the concordance with the Milan criteria correlated with MVI (P=0.018). No patient without MVI in the primary HCC revealed MVI on early recurrence (<2 years) (P=0.035).

Conclusions

HCC recurrences share many biological features of the primary tumor. Moreover, early recurrences of MVI-negative HCC never revealed MVI. This finding offers novel concepts, e.g., patient selection for salvage OLT.

High pre-treatment static and dynamic alpha-fetoprotein values predict reduced overall survival in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma is one of the most lethal cancers worldwide. Novel prognostic and/or predictive biomarkers are urgently needed to improve patient management. Alpha-fetoprotein is a well-established and widely used biomarker for hepatocellular carcinoma. However, diagnostic accuracy of static alpha-fetoprotein values is limited and the clinical potential is a matter of ongoing scientific discussion.

OBJECTIVE

We here evaluated the prognostic impact of pre-treatment static and dynamic alpha-fetoprotein variables on overall survival of hepatocellular carcinoma patients in a Western cohort.

METHODS

Patients with confirmed hepatocellular carcinoma (n = 809) treated at the Johannes Gutenberg-University Mainz between 1998 and 2014 and two available pre-treatment alpha-fetoprotein-values (AFP-slope) were retrospectively analysed. Clinico-pathological baseline parameters, pre-treatment static values and AFP-slope were assessed. Prognostic impact was determined by Kaplan-Meier analyses and Cox regression models.

RESULTS

High static and dynamic alpha-fetoprotein variables prior to therapy were associated with reduced survival rates of hepatocellular carcinoma patients. Several known clinical parameters such as Child-Pugh B (p < 0.01) and C stage (p < 0.001), portal vein thrombosis (p < 0.001) and extrahepatic spread (p < 0.001) were confirmed as independent predictors for overall survival. Addition of static and/or dynamic alpha-fetoprotein variable resulted in higher time-dependent area under the curves. Notably, in patients with more favourable prognosis, AFP-slope prior to therapy was a slightly stronger predictor for overall survival compared with static alpha-fetoprotein values.

CONCLUSION

Static and dynamic alpha-fetoprotein variables prior to therapy are predictive for overall survival of hepatocellular carcinoma patients. Addition of AFP-slope to established prognostic parameters might improve prognostic classification for a subgroup of hepatocellular carcinoma patients with preserved liver function and without portal vein tumour thrombosis.

Hepatitis E Is a Rare Finding in Liver Transplant Patients With Chronic Elevated Liver Enzymes and Biopsy-Proven Acute Rejection

BACKGROUND

In past decades, liver transplant (LT) patients were not routinely screened for hepatitis E virus (HEV) infection, and thus it might have been misdiagnosed as an acute rejection episode. Our aim was to analyze a real-world cohort of LT patients who presented with at least 1 episode of biopsy-proven acute rejection (BPAR) and suffered from persistent elevated transaminases, to evaluate the frequency of HEV infection misdiagnosed as a rejection episode.

METHODS

Data from 306 patients transplanted between 1997 and 2017, including 565 liver biopsies, were analyzed. Biopsies from patients suffering from hepatitis C (n = 79; 25.8%) and from patients who presented with a Rejection Activity Index <5 (n = 134; 43.8%) were excluded. A subgroup of 74 patients (with 134 BPAR) with persistently elevated liver enzymes was chosen for further HEV testing.

RESULTS

Positive HEV IgG was detectable in 18 of 73 patients (24.7%). Positive HEV RNA was diagnosed in 3 of 73 patients with BPAR (4.1%). Patients with HEV infection showed no difference in etiology of the liver disease, type of immunosuppression, or median Rejection Activity Index.

CONCLUSION

Few HEV infections were misdiagnosed as acute rejection episodes in this real-world cohort. Thus, HEV infection is an infrequent diagnosis in cases with persistent elevated liver enzymes and BPAR after LT.

Charting the Path Forward for Risk Prediction in Liver Transplant for Hepatocellular Carcinoma: International Validation of HALTHCC Among 4,089 Patients

Prognosticating outcomes in liver transplant (LT) for hepatocellular carcinoma (HCC) continues to challenge the field. Although Milan Criteria (MC) generalized the practice of LT for HCC and improved outcomes, its predictive character has degraded with increasing candidate and oncological heterogeneity. We sought to validate and recalibrate a previously developed, preoperatively calculated, continuous risk score, the Hazard Associated with Liver Transplantation for Hepatocellular Carcinoma (HALTHCC), in an international cohort. From 2002 to 2014, 4,089 patients (both MC in and out [25.2%]) across 16 centers in North America, Europe, and Asia were included. A continuous risk score using pre-LT levels of alpha-fetoprotein, Model for End-Stage Liver Disease Sodium score, and tumor burden score was recalibrated among a randomly selected cohort (n = 1,021) and validated in the remainder (n = 3,068). This study demonstrated significant heterogeneity by site and year, reflecting practice trends over the last decade. On explant pathology, both vascular invasion (VI) and poorly differentiated component (PDC) increased with increasing HALTHCC score. The lowest-risk patients (HALTHCC 0-5) had lower rates of VI and PDC than the highest-risk patients (HALTHCC > 35) (VI, 7.7%[ 1.2-14.2] vs. 70.6% [48.3-92.9] and PDC:4.6% [0.1%-9.8%] vs. 47.1% [22.6-71.5]; P < 0.0001 for both). This trend was robust to MC status. This international study was used to adjust the coefficients in the HALTHCC score. Before recalibration, HALTHCC had the greatest discriminatory ability for overall survival (OS; C-index = 0.61) compared to all previously reported scores. Following recalibration, the prognostic utility increased for both recurrence (C-index = 0.71) and OS (C-index = 0.63). Conclusion: This large international trial validated and refined the role for the continuous risk metric, HALTHCC, in establishing pre-LT risk among candidates with HCC worldwide. Prospective trials introducing HALTHCC into clinical practice are warranted.

Hepatocellular carcinoma recurrence after acute liver allograft rejection treatment: A multicenter European experience

BACKGROUND

During the last decades, several risk factors for the recurrence of hepatocellular carcinoma (HCC) after liver transplantation (LT) have been investigated. However, the impact of two important drivers of oncogenesis, namely the immunosuppression and the treatment of acute cellular rejection (ACR) have been marginally addressed. This study aimed at investigating the impact of ACR treatment on the incidence of tumor recurrence in a large European HCC-LT population.

METHODS

Seven hundred and eighty-one adult patients transplanted between February 1, 1985 and June 30, 2016 were retrospectively analyzed. After propensity score match, 116 patients treated for ACR using steroid boluses were compared with 115 patients who did not present any ACR or a histologic but clinical irrelevant ACR.

RESULTS

Steroid boluses treated patients had a 18-fold higher overall incidence of HCC recurrence than those non-treated patients (16.4% vs. 0.9%; P<0.0001). At multivariate Cox regression analysis, steroid boluses used to treat ACR were an independent risk factor for HCC recurrence (HR=14.2; 95% CI: 1.8-110.4; P = 0.010).

CONCLUSIONS

The decision to treat ACR as well as to reinforce immunosuppression load should be cautiously taken in view of the presented results. Prospective studies are needed to further elucidate the clinical impact of immunosuppression on HCC recurrence after transplantation.

The Intention-to-Treat Effect of Bridging Treatments in the Setting of Milan Criteria-In Patients Waiting for Liver Transplantation

In patients with hepatocellular carcinoma (HCC) meeting the Milan criteria (MC), the benefit of locoregional therapies (LRTs) in the context of liver transplantation (LT) is still debated. Initial biases in the selection between treated and untreated patients have yielded conflicting reported results. The study aimed to identify, using a competing risk analysis, risk factors for HCC-dependent LT failure, defined as pretransplant tumor-related delisting or posttransplant recurrence. The study was registered at www.clinicaltrials.gov (identification number NCT03723304). In order to offset the initial limitations of the investigated population, an inverse probability of treatment weighting (IPTW) analysis was used: 1083 MC-in patients (no LRT = 182; LRT = 901) were balanced using 8 variables: age, sex, Model for End-Stage Liver Disease (MELD) value, hepatitis C virus status, hepatitis B virus status, largest lesion diameter, number of nodules, and alpha-fetoprotein (AFP). All the covariates were available at the first referral. After the IPTW, a pseudo-population of 2019 patients listed for LT was analyzed, comparing 2 homogeneous groups of untreated (n = 1077) and LRT-treated (n = 942) patients. Tumor progression after LRT was the most important independent risk factor for HCC-dependent failure (subhazard ratio [SHR], 5.62; P < 0.001). Other independent risk factors were major tumor diameter, AFP, MELD, patient age, male sex, and period of wait-list registration. One single LRT was protective compared with no treatment (SHR, 0.51; P < 0.001). The positive effect was still observed when 2-3 treatments were performed (SHR, 0.66; P = 0.02), but it was lost in the case of ≥4 LRTs (SHR, 0.80; P = 0.27). In conclusion, for MC-in patients, up to 3 LRTs are beneficial for success in intention-to-treat LT patients, with a 49% to 34% reduction in failure risk compared with untreated patients. This benefit is lost if more LRTs are required. A poor response to LRT is associated with a higher risk for HCC-dependent transplant failure.

Long-term observation of hepatocellular carcinoma recurrence after liver transplantation at a European transplantation centre

Background

The recurrence of hepatocellular carcinoma (HCC) is the strongest survival-limiting factor after liver transplantation (LT) in patients with HCC. In the face of donor organ shortage, it is necessary to identify factors associated with HCC recurrence in order to maximize the utility of the available grafts.

Objective

To study the phenomenon of HCC recurrence after LT at a European transplantation centre over the past 20 years.

Methods

Data from 304 HCC patients who underwent LT were prospectively recorded. Clinical and pathological factors were assessed for their association with recurrence.

Results

Fifty-one patients (16.8%) had HCC recurrence after LT. Patients exceeding the Milan criteria developed HCC recurrence more frequently. The time point of recurrence did not affect survival after recurrence. Furthermore, there was no difference in survival between patients with intra- and extrahepatic recurrence. However, patients with recurrence due to needle tract seeding had a significantly better outcome than patients with other sites of recurrence.

Conclusion

Our data support a restrictive use of patient selection criteria to help identify patients who have an increased risk of HCC recurrence after LT, and highlight the need to improve patient selection before LT in order to minimize the rate of HCC recurrence.

Expression and prognostic significance of insulin‑like growth factor-2 receptor in human hepatocellular carcinoma and the influence of transarterial chemoembolization

Hepatocellular carcinoma (HCC) is one of the most common human malignancies, the incidence of which is growing worldwide. The prognosis of HCC is very poor and it is often accompanied by a high rate of recurrence. Conventional chemotherapeutic approaches are largely inefficient. In order to develop novel effective methods for the early detection and prognosis of HCC, novel markers and therapeutic targets are urgently required. The present study focused on the effects of the expression of the tumor suppressor gene insulin‑like growth factor‑2 receptor (IGF2R) on patient survival and tumor recurrence in patients with HCC; this study paid specific attention to the influence of transarterial chemoembolization (TACE) prior to surgery. The mRNA expression levels of IGF2R were measured in primary human HCC and corresponding non‑neoplastic tumor‑surrounding tissue (TST) by reverse transcription‑polymerase chain reaction (RT‑PCR) (n=92). Subsequently, the associations between IGF2R expression and clinicopathological parameters, outcomes of HCC and TACE pretreatment prior to surgery were determined. Furthermore, the effects of the IGF2R gene polymorphisms rs629849 and rs642588 on susceptibility and on clinicopathological features of HCC were investigated. RT‑PCR demonstrated that the mRNA expression levels of IGF2R were downregulated in HCC compared with in TST samples (P=0.004), which was associated with a worse recurrence‑free survival of patients with HCC (P=0.002) and a lower occurrence of cirrhosis (P=0.05). TACE‑pretreated patients with HCC (n=26) exhibited significantly higher IGF2R mRNA expression in tumor tissues (P=0.019). In addition, significantly more patients with HCC in the TACE‑pretreated group exhibited upregulated IGF2R mRNA expression compared with in the non‑treated patients (P=0.032). The IGF2R SNPs rs629849 and rs642588 were not significantly associated with HCC risk, whereas a homozygous IGF2R rs629849 GG genotype was associated with a significantly elevated risk of non‑viral liver cirrhosis (P=0.05). In conclusion, these data suggested an important role for IGF2R expression in HCC, particularly with regards to TACE treatment prior to surgery.

Donor Shortage in Germany: Impact on Short- and Long-Term Results in Liver Transplantation

With slightly more than 10 donors per million inhabitants, Germany belongs to the underdeveloped countries in Europe with regard to organ donation. Organ shortage is supposed to promote the usage of organs which are declined in case of less pronounced scarcity. This may result in deteriorated graft and patient survival. In the light of this situation, data on the centers' procedures and outcome of liver transplantation in Germany is presented based upon reports of Eurotransplant, the German Institutions for Quality Assessment, and the Deutsche Stiftung Organtransplantation. Surprisingly, along with an increasing organ scarcity, the outcome during waiting time and after transplantation has been improved. The 1- and 3-year patient survival improved by 7 and 9%, respectively. Reasons for this unexpected development are discussed.