[68Ga]Ga-RAYZ-8009: A Glypican-3-Targeted Diagnostic Radiopharmaceutical for Hepatocellular Carcinoma Molecular Imaging-A First-in-Human Case Series

Advances in application of serum biomarkers for screening and early diagnosis of hepatocellular carcinoma

Hepatocellular carcinoma (HCC) represents a major global health challenge, with early detection through surveillance of high-risk populations remaining critical for improving clinical outcomes. Serum biomarkers play a crucial role in the early detection of HCC. Currently, commonly used serological markers for HCC include alpha-fetoprotein (AFP), des-gamma-carboxy prothrombin, and the Lens culinaris agglutinin-reactive fraction of AFP. Other potential biomarkers under investigation include glypican-3, osteopontin, alpha-L-fucosidase, Dickkopf-1, heat shock protein 90α, and Golgi protein 73. With the advancement of liquid biopsy technologies, novel markers such as circulating tumor DNA, circulating tumor cells, microRNAs, and long non-coding RNAs have emerged as promising tools for early screening and diagnosis of HCC. This review aims to summarize the research progress and clinical applications of these biomarkers related to liver cancer, providing scientific evidence to enhance early diagnosis rates, improve prognosis, and ultimately reduce HCC-related mortality.

Development of a Cyclic TMTP1-Based PET Probe for Visualization of Hepatocellular Carcinoma

TMTP1 is a tumor-homing peptide that selectively targets highly metastatic tumor cells with XPNPEP2 identified as its potential targeting receptor. Although TMTP1-based molecular probes have been explored for imaging tumors such as hepatocellular carcinoma (HCC), their clinical translation has been hampered by factors including suboptimal tumor uptake and rapid systemic clearance. To study possible solution for addressing these challenges, a cyclic TMTP1 based positron emission tomography (PET) probe, [68Ga]Ga-DOTA-cTMTP1, was designed, synthesized, and evaluated for imaging HCC in small animal models. [68Ga]Ga-DOTA-cTMTP1 demonstrated favorable aqueous solubility, with a log D 7.4 value of -3.28 ± 0.05, and it exhibited excellent in vitro stability in phosphate buffered saline (PBS) and fetal bovine serum (FBS). Biodistribution studies revealed a certain level of tumor accumulation (0.98 ± 0.14%ID/g at 30 min) and retention (0.40 ± 0.11%ID/g at 120 min). Impressively, [68Ga]Ga-DOTA-cTMTP1 maintained high tumor-to-liver contrast over time, with ratios of 2.65 ± 0.45 at 30 min, 2.37 ± 0.07 at 60 min, and 2.14 ± 0.20 at 120 min. It also displayed capability of clear visualization of small HCC foci (<4 mm) in transgenic c-Myc liver tumor mice models, with tumor/liver ratios 2.20 ± 0.10 at 30 min, 2.26 ± 0.11 at 60 min, and 2.55 ± 0.44 at 120 min, respectively. Overall, this study highlights that [68Ga]Ga-DOTA-cTMTP1 has favorable pharmacokinetic and in vivo tumor imaging profile, and it is a highly promising probe for visualization of HCC microlesions. Development of PET probes based on cyclic TMTP1 is a promising approach for discovering novel imaging probes.

PET imaging of hepatocellular carcinoma with [124I]IV-14

BACKGROUND

Currently, positron emission tomography (PET) plays no clear role in clinical imaging and management of hepatocellular carcinoma (HCC). New radiotracers for new target(s) are needed for PET imaging of HCC. Uridine-cytidine kinase 2 (UCK2) is a rate-limiting enzyme of the pyrimidine salvage synthesis pathway to phosphorylate uridine and cytidine. Studies have demonstrated that UCK2 is overexpressed in many types of solid cancers including HCC and is associated with the poor prognosis and proliferation of HCC. This study reported PET imaging using a UCK2-specific radiotracer with a clinically relevant anima model of spontaneously occurring HCC in the woodchucks.

METHODS

This study used 3'-(E)-(2-iodovinyl) uridine (IV-14), which is derived from a UCK2-selective antitumor agent 3'-(Ethynyl)uridine (EUrd), a cytotoxic ribonucleoside analogs of uridine. By radiolabeling IV-14 with Iodine-124 (124I), a UCK2-specific radiotracer [124I]IV-14 was obtained for PET imaging of UCK2. A naturally occurring woodchuck model of HCC following chronic viral hepatitis infection was used for PET imaging. Potassium iodide (KI) was tested in one of the three animals to block possible uptake of free 124I from de-iodination of [124I]IV-14.

RESULTS

We confirmed that UCK2 expression is higher in the woodchuck model of HCC than in the surrounding hepatic tissue, similar to human UCK2 that is highly expressed in human HCC. PET imaging with [124I]IV-14 showed a strong uptake in woodchuck HCC with low background uptake at one-hour post-injection. De-iodination did not seem to be an issue for PET imaging.

CONCLUSION

Our results demonstrate that UCK2 is a viable target for imaging HCC and has the potential for targeted endoradiotherapy of HCC.

[18F]fluorodeoxyglucose and [18F]fluorocholine PET-CT for staging optimisation and treatment modification in hepatocellular carcinoma (PET-HCC01): a prospective multicentre study

BACKGROUND

The role of PET-CT with [18F]fluorodeoxyglucose ([18F]FDG) and [18F]fluorocholine ([18F]FCH) in staging hepatocellular carcinoma and treatment decisions has, to our knowledge, never been prospectively assessed.

METHODS

We conducted a multicentre prospective study (PET-HCC01) in nine hospitals in France, including patients aged 18 years or older with a first diagnosis of hepatocellular carcinoma classified as Barcelona Clinic Liver Cancer (BCLC) classification A to C (without metastasis). At study inclusion, patients underwent contrast-enhanced liver MRI and liver, chest, and pelvis CT scans. Patients subsequently underwent [18F]FCH and [18F]FDG PET-CT. A first tumour staging and treatment decision was recorded by the multidisciplinary tumour board at each centre using morphological imaging, blind to the results of the PET-CTs. After the results of the PET-CTs were revealed, a second tumour staging and treatment decision was recorded. The primary endpoint was the proportion of patients whose treatment was modified by PET-CTs. Analyses were done in the intention-to-image population, consisting of all patients who had undergone at least one PET-CT and were discussed by the multidisciplinary tumour board. This study was registered with ClinicalTrials.gov, NCT04391348.

FINDINGS

Between July 20, 2020, and April 27, 2023, 230 patients were enrolled. Among the 215 patients included in the intention-to-image population, the median age was 66·0 years (IQR 60·0-71·5), 193 (90%) were male, and 155 (73%) had cirrhosis. Hepatocellular carcinoma was classified as BCLC stage A in 140 (65%) patients, B in 48 (22%), and C without metastasis in 27 (13%) on the basis of morphological imaging. Potential new lesions were identified in 19 (9%) patients by PET-CT (eight by both tracers, six by [18F]FCH only, and five by [18F]FDG only) and in six of these patients, follow-up confirmed the diagnosis of hepatocellular carcinoma (one lesion in the adrenal gland, two in bones, two in the lymph node, and one intrahepatic). PET-CT modified BCLC stage in ten patients: disease stage for two patients moved from BCLC A to B, from BCLC A to C for two patients, from BCLC B to C for two patients, and from BCLC C without metastasis to BCLC C with metastasis for four patients. Planned treatment was modified for four patients (2% [95% CI 1-5]), below the prespecified threshold of clinical significance (10%).

INTERPRETATION

[18F]FDG and [18F]FCH-PET-CTs should not be systematically performed for staging a first diagnosis of hepatocellular carcinoma, as they modified treatment decisions only in a minority of patients.

FUNDING

Programme Hospitalier de Recherche Clinique Inter-regional-PHRC-I2018 (Ministère de la Santé).

Advances in radiation therapy for HCC: Integration with liver-directed treatments

HCC is the fourth leading cause of cancer-related mortality with increasing incidence worldwide. Historically, treatment for early disease includes liver transplantation, surgical resection, and/or other local therapies, such as thermal ablation. As a result of technical advances and high-quality prospective data, the use of definitive external beam radiotherapy with ablative doses has emerged. Intermediate-stage disease has been generally addressed with arterially directed therapies (eg, chemoembolization or radioembolization) and external beam radiotherapy, while advanced stages have been addressed by systemic therapy or best supportive care. The role of each local/locoregional therapy has rapidly evolved in the context of novel pharmacotherapies, including immunotherapies and antiangiogenic agents. The combinations, indications, and timing of treatments vary widely among specialties and geographies. Here, we aim to synthesize the best quality evidence available regarding the efficacy and safety of different liver-directed modalities, with a focus on recent prospective clinical data of external beam radiotherapy within the context of other available liver-directed therapies across Barcelona Liver Classification (BCLC) stages.

Integrating CT Radiomics and Clinical Features to Optimize TACE Technique Decision-Making in Hepatocellular Carcinoma

BACKGROUND/OBJECTIVES

To develop a decision framework integrating computed tomography (CT) radiomics and clinical factors to guide the selection of transarterial chemoembolization (TACE) technique for optimizing treatment response in non-resectable hepatocellular carcinoma (HCC).

METHODS

A retrospective analysis was performed on 151 patients [33 conventional TACE (cTACE), 69 drug-eluting bead TACE (DEB-TACE), 49 degradable starch microsphere TACE (DSM-TACE)] who underwent TACE for HCC at a single tertiary center. Pre-TACE contrast-enhanced CT images were used to extract radiomic features of the TACE-treated liver tumor volume. Patient clinical and laboratory data were combined with radiomics-derived predictors in an elastic net regularized logistic regression model to identify independent factors associated with early response at 4-6 weeks post-TACE. Predicted response probabilities under each TACE technique were compared with the actual techniques performed.

RESULTS

Elastic net modeling identified three independent predictors of response: radiomic feature "Contrast" (OR = 5.80), BCLC stage B (OR = 0.92), and viral hepatitis etiology (OR = 0.74). Interaction models indicated that the relative benefit of each TACE technique depended on the identified patient-specific predictors. Model-based recommendations differed from the actual treatment selected in 66.2% of cases, suggesting potential for improved patient-technique matching.

CONCLUSIONS

Integrating CT radiomics with clinical variables may help identify the optimal TACE technique for individual HCC patients. This approach holds promise for a more personalized therapy selection and improved response rates beyond standard clinical decision-making.

177Lu-Labeled Heterodimeric Agent with High Stability Targeting Neovascularization for Tumor Radioligand Therapy

Radiopharmaceutical theranostics holds significant promise in tumor diagnosis and treatment, but suboptimal tumor uptake and retention remain a persistent limitation. We have conjugated a unique albumin binder to our previously developed heterodimeric precursor HX01 and achieved a novel precursor L6, aiming to prolong circulation time and enhance tumor accumulation and retention. However, we observed that the NGR sequence of L6 was gradually rearranged to iso-DGR under alkaline conditions, resulting in decreased stability. In this study, we further modified the L6 to synthesize XH02, subsequently assessing their in vitro and in vivo properties following radiolabeling. Utilizing positron emission tomography (PET)/computed tomography (CT) imaging, single-photon emission computed tomography (SPECT)/CT imaging, and biodistribution study in BxPC-3 xenograft mice, we observed striking accumulation and retention of radiopharmaceutical within tumors. Two cycles of administration of 177Lu-XH02 displayed exceptional tumor growth inhibition in BxPC-3 tumors while causing minimal side effects. This promising result underscores the immense potential of this agent for further clinical translation and investigation.