Efficacy of Yttrium-90 Transarterial Radioembolisation in Advanced Hepatocellular Carcinoma: An Experience With Hybrid Angio-Computed Tomography and Glass Microspheres

Synthesis and characterization of functional chitosan-based microspheres as biodegradable yttrium-90 delivery system for radioembolization therapy

Transarterial radioembolization (TARE) using yttrium-90 (90Y)-labeled glass and resin microspheres is an emerging therapeutic technique for hepatocellular carcinoma (HCC). However, the non-biodegradability and rapid settlement of current commercial microspheres might hinder their even distribution and repetitive administration thus causing unsatisfactory therapeutic effects. In this context, novel functional chitosan-based microspheres (CPIs) that can efficiently label Y as a favorable TARE material were developed for the first time by successive grafting poly (glycidyl methacrylate) (PGMA) and iminodiacetic acid (IDA) onto chitosan microspheres (CMs). The results confirmed that the CPIs had desirable spherical shapes with average diameters of around 20.9 μm, an ideal settlement rate within 5 min, and considerable biodegradability at 10th weeks. It reached Y adsorption equilibrium within 30 min and maintained the maximum adsorption capacity up to 14.95 mg g-1 at pH 6.0 following pseudo-second-order kinetic and Langmuir models. Additionally, Y-labeled CPIs were rather stable in vitro, for which Y would firmly interact with the sodium carboxylate group and tertiary amine nitrogen atoms on IDA, and its leakage when shaken in phosphate-buffered saline for 24 h was barely detected. Altogether, these properties of the as-developed CPIs hold great potential as promising radioembolization microspheres for TARE therapy against liver cancer.

Advancements in Immunotherapeutic Treatments for Hepatocellular Carcinoma: Potential of Combination Therapies

Hepatocellular carcinoma (HCC) is the sixth most prevalent cancer and a significant global health burden, with increasing incidence rates and limited treatment options. Immunotherapy has become a promising approach due to its ability to affect the immune microenvironment and promote antitumor responses. The immune microenvironment performs an essential role in both the progression and the development of HCC, with different characteristics based on specific immune cells and etiological factors. Immune checkpoint inhibitors, including programmed death-1/programmed death-ligand 1 inhibitors (pembrolizumab, nivolumab, and durvalumab) and cytotoxic T lymphocyte antigen-4 inhibitors (tremelimumab and ipilimumab), have the potential to treat advanced HCC and overcome adverse effects, such as liver failure and chemoresistance. Phase II and phase III clinical trials highlight the efficacy of pembrolizumab and nivolumab, respectively, in advanced HCC patients, as demonstrated by their positive effects on overall survival and progression-free survival. Tremelimumab has exhibited modest response rates, though it does possess antiviral activity. Thus, it is still being investigated in ongoing clinical trials. Combination therapies with multiple drugs have demonstrated potential benefits in terms of survival and tumor response rates, improving patient outcomes compared to monotherapy, especially for advanced-stage HCC. This review addresses the clinical trials of immunotherapies for early-, intermediate-, and advanced-stage HCC. Additionally, it highlights how combination therapy can significantly enhance overall survival, progression-free survival, and objective response rate in advanced-stage HCC, where treatment options are limited.