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.

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.

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.

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.

Increasing donor risk, particularly in liver transplantation, where organs are often marginal, has made dynamic organ preservation techniques and viability assessment essential to safely improve organ quality and increase utilisation. However, existing viability parameters are based on routine clinical assessment in patients with acute liver failure, trauma, or liver resections. These parameters often do not correlate with clinically relevant post-transplant outcomes. This article presents a detailed protocol for the spectrophotometric quantification of Flavin mononucleotide (FMN), a marker of mitochondrial injury. FMN release from mitochondrial complex I was described many decades ago as the initial sign of ischaemia-reperfusion injury, i.e. when oxygen is reintroduced in ischaemic tissues during organ transplantation or machine perfusion. This study describes the detailed FMN quantification in donor plasma and various fluids obtained during machine perfusion, and discusses confounders, challenges, and the role of individual test components. FMN quantification was identified as an immediate organ assessment tool, demonstrating a strong correlation with graft survival and other relevant complications after human liver transplantation. The results highlight FMN quantification as a reliable and standardized method for assessing organ viability, offering significant potential for improving organ selection and better utilisation. This method could provide better a predictive value for transplant outcomes compared to existing parameters currently in use. This research received no external funding but was supported by the Catalyst grant No. CCG0280 at Cleveland Clinic Ohio, U.S. dedicated to A.S.

Background: Histotripsy is a novel, non-invasive, non-ionizing, and non-thermal ablation technique that disrupts tumors using acoustic cavitation. We report the first use of Histotripsy as bridging therapy prior to liver transplant for hepatocellular carcinoma (HCC) treated with histotripsy. Case presentation: A 59-year-old woman presented with Metabolic-Associated Steatotic Liver Disease (MASLD) cirrhosis (labMELD = 14), hepatic encephalopathy, and a single 2 cm OPTN V lesion in the left lateral segment consistent with HCC. The patient underwent histotripsy treatment of the lesion as bridging therapy before receiving liver transplantation. Histopathology analysis of the explanted liver showed total necrosis of the treated area, with no residual viable tissue tumor. Conclusion: This case demonstrates the potential utility of histotripsy as an effective bridging therapy for patients with combined cirrhosis and hepatocellular carcinoma (HCC) awaiting liver transplantation, with complete tumor necrosis on explant pathology demonstrating its therapeutic efficacy.