Impact of Back-to-Base Normothermic Machine Perfusion on Complications and Costs: A Multicenter, Real-World Risk-Matched Analysis.

OBJECTIVE: Assess cost and complication outcomes after liver transplantation (LT) using normothermic machine perfusion (NMP). BACKGROUND: End-ischemic NMP is often used to aid logistics, yet its impact on outcomes after LT remains unclear, as does its true impact on costs associated with transplantation. METHODS: Deceased donor liver recipients at 2 centers (January 1, 2019, to June 30, 2023) were included. Retransplants, splits, and combined grafts were excluded. End-ischemic NMP (OrganOx-Metra) was implemented in October 2022 for extended-criteria donation after brain death (DBDs), all donations after circulatory deaths (DCDs), and logistics. NMP cases were matched 1:2 with static cold storage controls (SCS) using the Balance-of-Risk [donation after brain death (DBD)-grafts] and UK-DCD Score (DCD-grafts). RESULTS: Overall, 803 transplantations were included, 174 (21.7%) receiving NMP. Matching was achieved between 118 NMP-DBDs with 236 SCS; and 37 NMP-DCD with 74 corresponding SCS. For both graft types, median inpatient comprehensive complications index values were comparable between groups. DCD-NMP grafts experienced reduced cumulative 90-day comprehensive complications index (27.6 vs 41.9, P =0.028). NMP also reduced the need for early relaparotomy and renal replacement therapy, with subsequently less frequent major complications (Clavien-Dindo ≥IVa). This effect was more pronounced in DCD transplants. NMP had no protective effect on early biliary complications. Organ acquisition/preservation costs were higher with NMP, yet NMP-treated grafts had lower 90-day pretransplant costs in the context of shorter waiting list times. Overall costs were comparable for both cohorts. CONCLUSIONS: This is the first risk-adjusted outcome and cost analysis comparing NMP and SCS. In addition to logistical benefits, NMP was associated with a reduction in relaparotomy and bleeding in DBD grafts, and overall complications and post-LT renal replacement for DCDs. While organ acquisition/preservation was more costly with NMP, overall 90-day health care costs-per-transplantation were comparable.

Intensive locoregional therapy before liver transplantation for colorectal cancer liver metastasis: A novel pretransplant protocol.

We describe a novel pre-liver transplant (LT) approach in colorectal liver metastasis, allowing for improved monitoring of tumor biology and reduction of disease burden before committing a patient to transplantation. Patients undergoing LT for colorectal liver metastasis at Cleveland Clinic were included. The described protocol involves intensive locoregional therapy with systemic chemotherapy, aiming to reach minimal disease burden revealed by positron emission tomography scan and carcinoembryonic Ag. Patients with no detectable disease or irreversible treatment-induced liver injury undergo transplant. Nine patients received liver transplant out of 27 who were evaluated (33.3%). The median follow-up was 700 days. Seven patients (77.8%) received a living donor LT. Five had no detectable disease, and 4 had treatment-induced cirrhosis. Pretransplant management included chemotherapy (n = 9) +/- bevacizumab (n = 6) and/or anti-EGFR (n = 6). The median number of pre-LT cycles of chemotherapy was 16 (range 10-40). Liver-directed therapy included Yttrium-90 (n = 5), ablation (n = 4), resection (n = 4), and hepatic artery infusion pump (n = 3). Three patients recurred after LT. Actuarial 1- and 2-year recurrence-free survival were 75% (n = 6/8) and 60% (n = 3/5). Recurrence occurred in the lungs (n = 1), liver graft (n = 1), and lungs+para-aortic nodes (n = 1). Patients with pre-LT detectable disease had reduced RFS ( p = 0.04). All patients with recurrence had histologically viable tumors in the liver explant. Patients treated in our protocol (n = 16) demonstrated improved survival versus those who were not candidates (n = 11) regardless of transplant status ( p = 0.01). A protocol defined by aggressive pretransplant liver-directed treatment and transplant for patients with the undetectable disease or treatment-induced liver injury may help prevent tumor recurrence.

The impact of normothermic machine perfusion and acuity circles on waitlist time, mortality, and cost in liver transplantation: A multicenter experience.

Ex situ normothermic machine perfusion (NMP) helps increase the use of extended criteria donor livers. However, the impact of an NMP program on waitlist times and mortality has not been evaluated. Adult patients listed for liver transplant (LT) at 2 academic centers from January 1, 2015, to September 1, 2023, were included (n=2773) to allow all patients ≥6 months follow-up from listing. Routine NMP was implemented on October 14, 2022. Waitlist outcomes were compared from pre-NMP pre-acuity circles (n=1460), pre-NMP with acuity circles (n=842), and with NMP (n=381). Median waitlist time was 79 days (IQR: 20-232 d) at baseline, 49 days (7-182) with acuity circles, and 14 days (5-56) with NMP ( p <0.001). The rate of transplant-per-100-person-years improved from 61-per-100-person-years to 99-per-100-person-years with acuity circles and 194-per-100-person-years with NMP ( p <0.001). Crude mortality without transplant decreased from 18.3% (n=268/1460) to 13.3% (n=112/843), to 6.3% (n=24/381) ( p <0.001) with NMP. The incidence of mortality without LT was 15-per-100-person-years before acuity circles, 19-per-100 with acuity circles, and 9-per-100-person-years after NMP ( p <0.001). Median Model for End-Stage Liver Disease at LT was lowest with NMP, but Model for End-Stage Liver Disease at listing was highest in this era ( p <0.0001). The median donor risk index of transplanted livers at baseline was 1.54 (1.27-1.82), 1.66 (1.42-2.16) with acuity circles, and 2.06 (1.63-2.46) with NMP ( p <0.001). Six-month post-LT survival was not different between eras ( p =0.322). The total cost of health care while waitlisted was lowest in the NMP era ($53,683 vs. $32,687 vs. $23,688, p <0.001); cost-per-day did not differ between eras ( p =0.152). The implementation of a routine NMP program was associated with reduced waitlist time and mortality without compromising short-term survival after liver transplant despite increased use of riskier grafts. Routine NMP use enables better waitlist management with reduced health care costs.

Neoadjuvant therapy reduces node positivity but does not confer survival benefit versus up-front resection for resectable intrahepatic cholangiocarcinoma: A propensity-matched analysis.

BACKGROUND: Neoadjuvant systemic therapy (NAST) is a treatment option for intrahepatic cholangiocarcinoma (iCCA), though its impact on short-term oncologic outcomes and long-term survival remains relatively unknown. METHODS: The National Cancer Database (NCDB) between 2004 and 2019 was queried for patients with reportedly resectable (Stage I-IIIB) iCCA who received curative-intent resection with lymphadenectomy. Propensity matching was performed between groups based on the use of NAST and groups were compared for overall survival (OS) and oncologic outcomes, including nodal harvest, rate of node positivity, rate of positive margins, and administration of adjuvant therapy. RESULTS: Two thousand and five hundred ninety-six patients met inclusion criteria; 364 (14%) received NAST versus 1763 (68%) up-front resection. After matching, 332 pairs of patients were matched between NAST and no NAST. Patients receiving NAST had a greater nodal harvest (OR = 1.26 [1.09-1.88]; p < 0.001) and a lower rate of node positivity (OR = 0.67 [0.49-0.63]; p < 0.001). Patients without NAST were more likely to complete adjuvant systemic therapy (OR = 0.45 [0.33-0.62]; p < 0.001). However, patients receiving NAST had no OS benefit after resection compared to those who did not receive NAST (median OS 48.3 ± 5.3 vs. 38.8 ± 3.7 months; p = 0.160). Node-positive disease (OR = 2.10 [1.78-2.45]; p < 0.001) conferred the greatest risk for reduced OS followed by positive-margin resection (OR = 1.42 [1.21-1.47]; p < 0.001) and increasing T-stage (OR = 1.34 [1.21-1.47]; p < 0.001). CONCLUSION: NAST for iCCA was associated with improved quality of oncologic resection but did not confer an OS benefit versus up-front resection.

Impact of autotransfusion on recurrence of colorectal cancer liver metastasis: Long-term follow-up of patients undergoing curative intent hepatectomy.

INTRODUCTION: Colorectal cancer liver metastasis (CRLM) occurs in upto 50% of cases and drives patient outcomes. Up-front liver resection is the treatment of choice in resectable cases. There is no consensus yet established as to the safety of intraoperative autotransfusion in liver resection for CRLM. METHODS: Patients undergoing curative-intent hepatectomy for CRLM at a single quaternary-care institution from 1999 to 2016 were included. Demographics, surgical variables, Fong Clinical Risk Score (FCRS), use of intraoperative auto and/or allotransfusion, and survival data were analyzed. Propensity score matching (PSM) was performed accounting for allotransfusion, extent of hepatectomy, FCRS, and systemic treatment regimens. RESULTS: Three-hundred sixteen patients were included. The median follow-up was 10.4 years (7.8-14.1 years). The median recurrence-free survival (RFS) and overall survival (OS) in all patients were 1.6 years (interquartile range: 0.63-6.6 years) and 4.4 years (2.1-8.7), respectively.  Before PSM, there was a significantly reduced RFS in the autotransfusion group (0.96 vs. 1.73 years, p = 0.20). There was no difference in OS (4.11 vs. 4.44 years, p = 0.118). Patients in groups of FCRS 0-2 and 3-5 both had reduced RFS when autotransfusion was used (p = 0.005). This reduction in RFS was further found when comparing autotransfusion versus no autotransfusion within the FCRS 0-2 group and within the FCRS 3-5 group (p = 0.027). On Cox-regression analysis, autotransfusion (hazard ratio = 1.423, 1.028-2.182, p = 0.015) remained predictive of RFS. After PSM, there were no differences in FCRS (p = 0.601), preoperative hemoglobin (p = 0.880), allotransfusion (p = 0.130), adjuvant chemotherapy (p = 1.000), immunotherapy (p = 0.172), tumor grade (p = 1.000), use of platinum-based chemotherapy (p = 0.548), or type of hepatic resection (p = 0.967). After matching, there was a higher rate of recurrence with autotransfusion (69.0% vs. 47.6%, p = 0.046). There was also a reduced time to recurrence in the autotransfusion group compared with the group without (p = 0.006). There was no difference in OS after PSM (p = 0.262). CONCLUSION: Autotransfusion may adversely affect recurrence in liver resection for CRLM. Until further studies clarify this risk profile, the use of intraoperative autotransfusion should be critically assessed on a case-by-case basis only when other resuscitation options are not available.

Intrinsic supercurrent non-reciprocity coupled to the crystal structure of a van der Waals Josephson barrier.

Non-reciprocal electronic transport in a spatially homogeneous system arises from the simultaneous breaking of inversion and time-reversal symmetries. Superconducting and Josephson diodes, a key ingredient for future non-dissipative quantum devices, have recently been realized. Only a few examples of a vertical superconducting diode effect have been reported and its mechanism, especially whether intrinsic or extrinsic, remains elusive. Here we demonstrate a substantial supercurrent non-reciprocity in a van der Waals vertical Josephson junction formed with a Td-WTe2 barrier and NbSe2 electrodes that clearly reflects the intrinsic crystal structure of Td-WTe2. The Josephson diode efficiency increases with the Td-WTe2 thickness up to critical thickness, and all junctions, irrespective of the barrier thickness, reveal magneto-chiral characteristics with respect to a mirror plane of Td-WTe2. Our results, together with the twist-angle-tuned magneto-chirality of a Td-WTe2 double-barrier junction, show that two-dimensional materials promise vertical Josephson diodes with high efficiency and tunability.

Emerging and Clinically Accepted Biomarkers for Hepatocellular Carcinoma.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death and the sixth most diagnosed malignancy worldwide. Serum alpha-fetoprotein (AFP) is the traditional, ubiquitous biomarker for HCC. However, there has been an increasing call for the use of multiple biomarkers to optimize care for these patients. AFP, AFP-L3, and prothrombin induced by vitamin K absence II (DCP) have described clinical utility for HCC, but unfortunately, they also have well established and significant limitations. Circulating tumor DNA (ctDNA), genomic glycosylation, and even totally non-invasive salivary metabolomics and/or micro-RNAS demonstrate great promise for early detection and long-term surveillance, but still require large-scale prospective validation to definitively validate their clinical validity. This review aims to provide an update on clinically available and emerging biomarkers for HCC, focusing on their respective clinical strengths and weaknesses.

Expanding Selection Criteria in Deceased Donor Liver Transplantation for Hepatocellular Carcinoma: Long-term Follow-up of a National Registry and 2 Transplant Centers.

BACKGROUND: This study compares selection criteria for liver transplant (LT) for hepatocellular carcinoma (HCC) for inclusivity and predictive ability to identify the most permissive criteria that maintain patient outcomes. METHODS: The Scientific Registry of Transplant Recipients (SRTR) database was queried for deceased donor LT's for HCC (2003-2020) with 3-y follow-up; these data were compared with a 2-center experience. Milan, University of California, San Francisco (UCSF), 5-5-500, Up-to-seven (U7), HALT-HCC, and Metroticket 2.0 scores were calculated. RESULTS: Nationally, 26 409 patients were included, and 547 at the 2 institutions. Median SRTR-follow-up was 6.8 y (interquartile range 3.9-10.1). Three criteria allowed the expansion of candidacy versus Milan: UCSF (7.7%, n = 1898), Metroticket 2.0 (4.2%, n = 1037), and U7 (3.5%, n = 828). The absolute difference in 3-y overall survival (OS) between scores was 1.5%. HALT-HCC (area under the curve [AUC] = 0.559, 0.551-0.567) best predicted 3-y OS although AUC was notably similar between criteria (0.506 < AUC < 0.527, Mila n = 0.513, UCSF = 0.506, 5-5-500 = 0.522, U7 = 0.511, HALT-HCC = 0.559, and Metroticket 2.0 = 0.520), as was Harrall's c-statistic (0.507 < c-statistic < 0.532). All scores predicted survival to P < 0.001 on competing risk analysis. Median follow-up in our enterprise was 9.8 y (interquartile range 7.1-13.3). U7 (13.0%, n = 58), UCSF (11.1%, n = 50), HALT-HCC (6.4%, n = 29), and Metroticket 2.0 (6.3%, n = 28) allowed candidate expansion. HALT-HCC (AUC = 0.768, 0.713-0.823) and Metroticket 2.0 (AUC = 0.739, 0.677-0.801) were the most predictive of recurrence. All scores predicted recurrence and survival to P < 0.001 using competing risk analysis. CONCLUSIONS: Less restrictive criteria such as Metroticket 2.0, UCSF, or U7 allow broader application of transplants for HCC without sacrificing outcomes. Thus, the criteria for Model for End-stage Liver Disease-exception points for HCC should be expanded to allow more patients to receive life-saving transplantation.

Risk assessment in liver transplantation for hepatocellular carcinoma: long-term follow-up of a two-centre experience.

BACKGROUND: Liver transplantation (LT) is a well-established treatment for hepatocellular carcinoma (HCC), but there are ongoing debates regarding outcomes and selection. This study examines the experience of LT for HCC at a high-volume centre. METHODS: A prospectively maintained database was used to identify HCC patients undergoing LT from 2000 to 2020 with more than or equal to 3-years follow-up. Data were obtained from the centre database and electronic medical records. The Metroticket 2.0 HCC-specific 5-year survival scale was calculated for each patient. Kaplan-Meier and Cox-regression analyses were employed assessing survival between groups based on Metroticket score and individual donor and recipient risk factors. RESULTS: Five hundred sixty-nine patients met criteria. Median follow-up was 96.2 months (8.12 years; interquartile range 59.9-147.8). Three-year recurrence-free (RFS) and overall survival (OS) were 88.6% ( n =504) and 86.6% ( n =493). Five-year RFS and OS were 78.9% ( n =449) and 79.1% ( n =450). Median Metroticket 2.0 score was 0.9 (interquartile range 0.9-0.95). Tumour size greater than 3 cm ( P =0.012), increasing tumour number on imaging ( P =0.001) and explant pathology ( P <0.001) was associated with recurrence. Transplant within Milan ( P <0.001) or UCSF criteria ( P <0.001) had lower recurrence rates. Increasing alpha-fetoprotein (AFP)-values were associated with more HCC recurrence ( P <0.001) and reduced OS ( P =0.008). Chemoembolization was predictive of recurrence in the overall population ( P =0.043) and in those outside-Milan criteria ( P =0.038). A receiver-operator curve using Metroticket 2.0 identified an optimal cut-off of projected survival greater than or equal to 87.5% for predicting recurrence. This cut-off was able to predict RFS ( P <0.001) in the total cohort and predict both, RFS ( P =0.007) and OS ( P =0.016) outside Milan. Receipt of donation after brain death (DBD) grafts (55/478, 13%) or living-donor grafts (3/22, 13.6%) experienced better survival rates compared to donation after cardiac death (DCD) grafts ( n =15/58, 25.6%, P =0.009). Donor age was associated with a higher HCC recurrence ( P =0.006). Both total ischaemia time (TIT) greater than 6hours ( P =0.016) and increasing TIT correlated with higher HCC recurrence ( P =0.027). The use of DCD grafts for outside-Milan candidates was associated with increased recurrence ( P =0.039) and reduced survival ( P =0.033). CONCLUSION: This large two-centre analysis confirms favourable outcomes after LT for HCC. Tumour size and number, pre-transplant AFP, and Milan criteria remain important recipient HCC-risk factors. A higher donor risk (i.e. donor age, DCD grafts, ischaemia time) was associated with poorer outcomes.

Circulating Tumor DNA Profiling in Liver Transplant for Hepatocellular Carcinoma, Cholangiocarcinoma, and Colorectal Liver Metastases: A Programmatic Proof of Concept.

INTRODUCTION: Circulating tumor DNA (ctDNA) is emerging as a promising, non-invasive diagnostic and surveillance biomarker in solid organ malignancy. However, its utility before and after liver transplant (LT) for patients with primary and secondary liver cancers is still underexplored. METHODS: Patients undergoing LT for hepatocellular carcinoma (HCC), cholangiocarcinoma (CCA), and colorectal liver metastases (CRLM) with ctDNA testing were included. CtDNA testing was conducted pre-transplant, post-transplant, or both (sequential) from 11/2019 to 09/2023 using Guardant360, Guardant Reveal, and Guardant360 CDx. RESULTS: 21 patients with HCC (n = 9, 43%), CRLM (n = 8, 38%), CCA (n = 3, 14%), and mixed HCC/CCA (n = 1, 5%) were included in the study. The median follow-up time was 15 months (range: 1-124). The median time from pre-operative testing to surgery was 3 months (IQR: 1-4; range: 0-5), and from surgery to post-operative testing, it was 9 months (IQR: 2-22; range: 0.4-112). A total of 13 (62%) patients had pre-transplant testing, with 8 (62%) having ctDNA detected (ctDNA+) and 5 (32%) not having ctDNA detected (ctDNA-). A total of 18 (86%) patients had post-transplant testing, 11 (61%) of whom were ctDNA+ and 7 (33%) of whom were ctDNA-. The absolute recurrence rates were 50% (n = 5) in those who were ctDNA+ vs. 25% (n = 1) in those who were ctDNA- in the post-transplant setting, though this difference was not statistically significant (p = 0.367). Six (29%) patients (HCC = 3, CCA = 1, CRLM = 2) experienced recurrence with a median recurrence-free survival of 14 (IQR: 6-40) months. Four of these patients had positive post-transplant ctDNA collected following diagnosis of recurrence, while one patient had positive post-transplant ctDNA collected preceding recurrence. A total of 10 (48%) patients had sequential ctDNA testing, of whom n = 5 (50%) achieved ctDNA clearance (+/-). The remainder were ctDNA+/+ (n = 3, 30%), ctDNA-/- (n = 1, 10%), and ctDNA-/+ (n = 1, 11%). Three (30%) patients showed the acquisition of new genomic alterations following transplant, all without recurrence. Overall, the median tumor mutation burden (TMB) decreased from 1.23 mut/Mb pre-transplant to 0.00 mut/Mb post-transplant. CONCLUSIONS: Patients with ctDNA positivity experienced recurrence at a higher rate than the ctDNA- patients, indicating the potential role of ctDNA in predicting recurrence after curative-intent transplant. Based on sequential testing, LT has the potential to clear ctDNA, demonstrating the capability of LT in the treatment of systemic disease. Transplant providers should be aware of the potential of donor-derived cell-free DNA and improved approaches are necessary to address such concerns.