Torbenson, Michael

Abstract Background Optimal treatment following first-line immunotherapy for advanced hepatocellular carcinoma (HCC) remains uncertain. This study evaluated futibatinib, a pan-FGFR inhibitor, combined with pembrolizumab in previously treated patients with FGF19-expressing HCC. Methods Eligible patients were ≥18 years old with advanced HCC, prior systemic therapy, Child-Pugh A-B7 liver function, ECOG 0–2, and FGF19 overexpression. Patients received futibatinib 20 mg orally daily plus pembrolizumab 200 mg intravenously every 3 weeks. The primary endpoint was progression-free survival at 6 months (PFS6). Secondary endpoints included overall survival (OS), objective response rate (ORR), quality of life, and safety. Results Between August 2021 and March 2024, 14 patients enrolled and 13 were evaluable. Median age was 72 years (range, 60–87), 53.8% were male, 92.3% had Child-Pugh A liver function, and all had received prior immunotherapy. Median progression-free survival was 15 weeks (95% CI, 9.0–NE), with a PFS6 rate of 23.1% (95% CI, 8.6–62.3%). ORR was 0% (95% CI, 0–24.7%), while stable disease was observed in 53.9% of patients. Median OS was 55.7 weeks (95% CI, 47.3–NE). Grade ≥3 adverse events occurred in 69.2% of patients, and grade ≥4 adverse events in 15.4%. One grade 5 event (acute-on-chronic kidney injury) was deemed unrelated to treatment. Common adverse events included hyperphosphatemia, fatigue, diarrhea, elevated transaminases, dry eye, nail changes, rash, and oral mucositis. Conclusions Futibatinib plus pembrolizumab demonstrated an acceptable safety profile but did not meet efficacy thresholds supporting further study in FGF19-expressing HCC. Effective post-immunotherapy treatment strategies remain an unmet need.

Abstract Prostate-specific membrane antigen (PSMA) is highly expressed in tumor-associated neovasculature in hepatocellular carcinoma (HCC), highlighting its promise as a theranostic target. This prospective study aimed to evaluate the utility of novel biomarkers derived from PSMA positron emission tomography computed tomography (PET/CT) to assess treatment response in advanced HCC patients (pts) receiving first line immune checkpoint inhibitors (ICI). Methods: This study (NCT05176223) enrolled unresectable, advanced HCC pts eligible for first-line ICI (atezolizumab/bevacizumab [A/B] or durvalumab/tremelimumab [D/T]) with measurable disease according to RECIST criteria. Primary endpoints: progression-free survival (PFS) per RECIST 1.1 and mRECIST; overall survival (OS); and best overall response. The survival distribution was estimated using the Kaplan-Meier method. Observed agreement is defined as the proportion of pts whose responses, as classified by PET/CT or CT, were concordant. Weighted kappa and Cohen’s kappa were used to quantify the strength of agreement between PET/CT and CT. Pts completed up to five 68Ga-PSMA PET/CT scans and blood collections. Results: Twenty-six pts were enrolled (25 evaluable) between Oct 2022 and Nov 2024. Median follow up was 22.1 months (m) (Q1, Q3: 14.5-23.7). Median age 68 yrs, 72% male, 88% White, 68% Child-Pugh [CP] A, 32% CP B, 32% Barcelona Clinic Liver Cancer [BCLC] stage B, 68% BCLC stage C, 36% with microvascular invasion; 56% received A/B and 40% received D/T treatment. PSMA was positive in 96% of pts at baseline with median SUVmax 14.3 (range 5.1-40.5) and median background liver SUVmax 3.9 (range 2.1-6.8). Median (95%CI) PFS was 5.6 m (4.6-12.5) by both RECIST and mRECIST. Median (95%CI) OS was 18.6 m (7.2-not estimable), with 56% deceased. The observed agreement between PET/CT adapted PERCIST criteria compared to RECIST and mRECIST in determining the best response was 46% and 50% and weighted kappa of 0.63 (95% CI: 0.37-0.90) and 0.66 (0.41-0.92), respectively. Observed agreement between PERCIST compared to RECIST and mRECIST for responders’ assessment was 67% and 71% with Cohen’s kappa of 0.36 (0.03-0.68) and 0.43 (0.11-0.76), respectively. Conclusion: In this cohort, PSMA PET/CT avidity was observed in all but one pt with advanced HCC, each demonstrating moderate to high SUVmax values. Median OS and PFS were consistent with outcomes reported in clinical trials. Response assessment using 68Ga-PSMA PET/CT according to PERCIST criteria showed good concordance with both RECIST and mRECIST standards. Analysis of immune biomarkers is ongoing. Citation Format: Nguyen H. Tran, Jacob Hirdler, Ajith Antony, Jacob Teske, Sudhakar K. Venkatesh, Amit Mahipal, Michael S. Torbenson, Scott M. Thompson, Thor R. Halfdanarson, Zhaohui Jin, Lionel Aurelien Kankeu Fonkoua, Leslie A. Washburn, Alexander Revzin, Haidong Dong, Robert R. Mcwilliams, Aminah Jatoi, Hani M. Babiker, Mitesh J. Borad, Tanios Bekaii-Saab, Gregory J. Gores, Lewis R. Roberts, Geoffrey B. Johnson, Ajit H. Goenka. Prospective evaluation of 68Ga-PSMA PET imaging in advanced hepatocellular carcinoma patients undergoing first line immunotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 2611.

CTNNB1- mutated hepatocellular carcinomas are characterized by a distinctive morphology and activation of the Wnt pathway. AXIN1 also plays a key role in the Wnt pathway, but the morphology of AXIN1-mutated tumors has not been examined. In addition, there are ongoing questions on the ability of AXIN1 mutations to activate the Wnt pathway in hepatocellular carcinoma. AXIN1 mutated tumors (N=18) were studied, along with control groups: CTNNB1 (N=17), APC (6), or “Other” genes in the Wnt pathway (5). Wnt pathway activation was studied by immunostains for beta-catenin and glutamine synthetase. Findings were supplemented by gene expression analysis using TCGA data. On histologic examination, the classic morphology associated with beta-catenin mutations was found in all 4 groups: 8/18 AXIN1 (44%), 10/17 CTNNB1 (59%), 4/6 APC (67%), and 1/5 Other (20%). By immunohistochemistry, Wnt pathway activation was found in 11/18 AXIN1 (61%), 15/17 CTTNB1 (88%), 6/6 APC (100%), and 5/5 (100%) of Other. In AXIN1- mutated tumors, the Wnt pathway was weakly activated. Glutamine synthetase stains also highlighted a new “progressed pattern” associated with distinct subnodules of staining. Tertiary lymphoid structures were uncommon except for cases with CTTNNB1 mutations plus additional mutations in the Wnt pathway. In summary, the classic morphology associated with CTNNB1 mutations is found in hepatocellular carcinomas with mutations in AXIN1 , APC , and other Wnt genes. AXIN1 mutated tumors have Wnt activation that is detectable but at lower levels than CTNNB1 mutated tumors. As tumors progress, their level of Wnt activation can change.

ABSTRACT Hepatoid adenocarcinoma (HAC) is a rare extrahepatic tumor of non‐germ cell origin that morphologically resembles hepatocellular carcinoma (HCC). HAC has a propensity to metastasize to the liver and therefore may be mistaken for HCC. There is a lack of standardized treatment protocols, and further studies are needed to evaluate the benefit of targeted therapy and immunotherapy. Recent studies have reported that tumor protein 53 ( TP53 ) gene mutations are associated with increased expression of programmed cell death ligand‐1 (PD‐L1), which may be a predictor of response to PD‐L1 targeted checkpoint inhibitors. This review provides a clinical guidance for the management of patients with HAC by summarizing the salient clinical features, risk factors, diagnostic criteria, differential diagnosis, new therapeutic approaches, and prognosis of this rare tumor. Furthermore, we reviewed the Mayo Clinic experience to describe the clinical characteristics of 15 patients diagnosed with HAC. HAC is usually diagnosed at an advanced stage with distant metastases. In patients diagnosed with liver lesions that have similar radiologic and histologic features to HCC, particularly in the absence of underlying chronic liver disease, further evaluation should be performed to rule out HAC. Communication between medical subspecialties is important to avoid misdiagnosis and prevent further disease progression. In our patient cohort TP53 was the most frequently mutated gene (5 out of 8, 62.5%) and PD‐L1 expression showed a positive score in 3 out of 6 patients (50%). However, only a few patients received immunotherapy (6 out of 14, 42.9%) suggesting that the numbers are too small to draw a conclusion about its efficacy in treating HAC.

Abstract Background Unresectable hepatocellular carcinoma (uHCC) is a leading cause of cancer death. FDA-approved first-line systemic therapies include atezolizumab/bevacizumab (atezo/bev) and durvalumab/tremelimumab (durva/treme); however, there is a lack of comparative data. Methods We reviewed outcomes of patients with uHCC who initiated atezo/bev or durva/treme between 2017 and 2024, across six institutions. Overall survival (OS) and time to treatment discontinuation (TTD) were analyzed using the Kaplan–Meier and Cox models, adjusting for baseline characteristics. Results Four hundred fifty-two uHCC pts were included. Median age: 68 years; 77% male; 81% white. Most common etiologies were viral hepatitis (38.9%) and metabolic dysfunction-associated steatohepatitis (19.5%). Disease progression was the primary reason for treatment discontinuation, atezo/bev (56%) and durva/treme (42%). Outcomes were not statistically significant (median OS [month, m]: 14.0 vs 14.6 [P = .66]; median TTD [m]: 4.9 vs 3.9 [P = .42] for atezo/bev vs durva/treme). Outcomes were significantly different between Child-Pugh classes (CP: A, B7, B8/9, C) respectively, median OS(m): 19.0, 6.1, 5.1, 2.0 (P < .001); median TTD(m): 6.1, 2.3, 3.0, 1.3 (P < .001). Conclusions In this real-world study of uHCC, no significant difference in clinical outcomes was observed between atezo/bev and durva/treme in the first-line setting. CP scores were a key prognostic variable with both regimens.

Understanding the imaging appearance of autoimmune disorders of the liver and biliary tract is important to guide further workup, suggest a particular diagnosis, monitor for disease progression or response to treatment, and evaluate for complications.

AbstractThe gold standard for enrollment and endpoint assessment in metabolic dysfunction‐associated steatosis clinical trials is histologic assessment of a liver biopsy performed on glass slides. However, obtaining the evaluations from several expert pathologists on glass is challenging, as shipping the slides around the country or around the world is time‐consuming and comes with the hazards of slide breakage. This study demonstrated that pathologic assessment of disease activity in steatohepatitis, performed using digital images on the AISight whole slide image management system, yields results that are comparable to those obtained using glass slides. The accuracy of scoring for steatohepatitis (nonalcoholic fatty liver disease activity score ≥4 with ≥1 for each feature and absence of atypical features suggestive of other liver disease) performed on the system was evaluated against scoring conducted on glass slides. Both methods were assessed for overall percent agreement with a consensus “ground truth” score (defined as the median score of a panel of three pathologists’ glass slides). Each case was also read by three different pathologists, once on glass and once digitally with a minimum 2‐week washout period between the modalities. It was demonstrated that the average agreement across three pathologists of digital scoring with ground truth was noninferior to the average agreement of glass scoring with ground truth [noninferiority margin: −0.05; difference: −0.001; 95% CI: (−0.027, 0.026); and p < 0.0001]. For each pathologist, there was a similar average agreement of digital and glass reads with glass ground truth (pathologist A, 0.843 and 0.849; pathologist B, 0.633 and 0.605; and pathologist C, 0.755 and 0.780). Here, we demonstrate that the accuracy of digital reads for steatohepatitis using digital images is equivalent to glass reads in the context of a clinical trial for scoring using the Clinical Research Network scoring system.

Abstract Fibrolamellar carcinoma (FLC) is a rare, usually lethal primary liver tumor that affects children, adolescents and young adults. Sequencing of FLC tumors in hepatocytes reveals that in 99% of the patients there is one recurrent genomic alteration: A deletion of 400 kB. This produces DNAJB1::PRKACA, a fusion of the first exon of DNAJB1 with the 2nd – 10th exons of PRKACA, the catalytic subunit of protein kinase A (PKA). PKA exists as a holoenzyme of two catalytic subunits and two regulatory subunits. The regulatory subunit both inhibits the catalytic and localizes it in the cell. Calibrated mass spectrometry shows that in normal liver there is always an excess of regulatory&gt;catalytic subunits, but in the adjacent FLC tumor tissue there is an excess of catalytic&gt;regulatory subunits. Different biochemistry assays and proximity ligation reveal both free catalytic, unbound to regulatory subunits, and an increase of kinase activity in the tumor cells. Much of the increase of catalytic subunit is in the nucleus. Transducing primary human hepatocytes (PHH) with DNAJB1::PRKACA is sufficient to recapitulate the transcriptome of FLC tumors. Transduction of PHH with just the wt PRKACA is also sufficient to recapitulate the transcriptome of FLC tumors. Thus, just increasing the level of kinase is sufficient, there is nothing special about the fusion domain. From our tissue repository we have four patients who have a tumor that looks like FLC but does not have a fusion to the catalytic subunit. The only alteration in these patients is loss of regulatory subunit. The transcriptome of these patient tumors is indistinguishable from that of classic DNAJB1::PRKACA FLC in hepatocytes. Additionally, we have a few dozen patients who have either DNAJB1::PRKACA or another fusion, ATP1B1::PRKACA in the ductal cells of their liver (producing cholangiocarcinomas) or ductal cells of their pancreas (producing IOPN, Intraductal Oncolytic Pancreatic Neoplasms). The transcriptome of these patients clusters with the transcriptome of the FLC patients with DNAJB1::PRKACA in the hepatocytes. A functional precision medicine drug repurposing screen found that the EC50 of the response of freshly resected tumors from patients to a wide panel of drugs is the same as that of FLC patients with DNAJB1::PRKACA in their hepatocytes. Based on sequencing one could conclude that patients with deletion of regulatory subunit in the hepatocytes, or expression of DNAJB1::PRKACA in the hepatocytes, or expression of DNAJB1::PRKACA or ATP1B1::PRKACA in the cholangiocytes or pancreatic ductal cells are at least three distinct diseases. An analysis of the cell biological changes reveals that they all of an increase of the ratio of catalytic:regulatory subunit, they have an increase of catalytic subunit in the nucleus, and these all result in the same changes of transcriptome and the same drug-response profile. Thus, looking beyond sequencing to the cellular changes leads to a different conclusion, that maybe they should be considered the same disease. Citation Format: Sanford Simon, Mahsa Shirani, David Requena, Denise Ng, Gadi Lalazar, Solomon Levin, Michael S. Torbenson, Aatur D. Singhi, Henrik Molina, Charles M. Rice, Philip Coffino, Barbara A. Lyons. Precision medicine for the fusion protein driven cancer, fibrolamellar carcinoma (FLC): Beyond sequencing [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Advances in Pediatric Cancer Research; 2024 Sep 5-8; Toronto, Ontario, Canada. Philadelphia (PA): AACR; Cancer Res 2024;84(17 Suppl):Abstract nr B022.