Carbon Ion Radiotherapy in the Treatment of Hepatocellular Carcinoma

Abstract

Hepatocellular carcinoma (HCC) is a highly lethal cancer with limited treatment options and poor prognosis. Carbon ion radiotherapy (CIRT) has emerged as a promising treatment modality for HCC due to its unique physical and biological properties. CIRT uses carbon ions to target and destroy cancer cells with a high precision and efficacy. The Bragg Peak phenomenon allows precise dose delivery to the tumor while minimizing damage to healthy tissues. In addition, the high relative biological effectiveness of carbon ions can be shown against radioresistant and hypoxic tumor areas. CIRT also offers a shorter treatment schedule than conventional radiotherapy, which increases patient convenience and compliance. The clinical outcomes of CIRT for HCC have shown excellent local control rates with minimal side effects. Considering its physical and biological properties, CIRT may be a viable option for complex clinical scenarios such as patients with poor liver function, large tumors, re-irradiation cases, and tumors close to critical organs. Further research and larger studies are needed to establish definitive indications for CIRT and to compare its efficacy with that of other treatment modalities. Nevertheless, CIRT offers a potential breakthrough in HCC management, providing hope for improved therapeutic outcomes and reduced treatment-related toxicities.

Current perspectives on radiotherapy in hepatocellular carcinoma management: a comprehensive review

“… 38 - 46 Furthermore, proton beam therapy (PBT) and carbon ion RT (CIRT) have been proven through various studies to provide outstanding disease control and acceptable toxicity. 19 , 22 , 25 , 47 - 64 Recent research has shifted focus toward the combined therapy of EBRT with other modalities or the potential of EBRT as an alternative to conventional local treatments in specific liver locations or depending on the patient’s condition and liver function. 65 - 68 Numerous comparative studies are being reported in this area.…”

“…In HCC treatment, CIRT has recently been recognized as a noteworthy therapeutic approach. 64 CIRT, a form of particle RT, leverages carbon ion beams for precise targeting and eradication of cancer cells. 64 The primary advantages of CIRT lie in its distinctive physical and biological characteristics.…”

“… 64 CIRT, a form of particle RT, leverages carbon ion beams for precise targeting and eradication of cancer cells. 64 The primary advantages of CIRT lie in its distinctive physical and biological characteristics. 115 These carbon ions can deposit concentrated energy within a limited tissue volume, inflicting greater damage to cancer cells with superior biological effectiveness than photons or protons.…”

“…Additionally, the unique dose distribution of carbon ions facilitates administering a high radiation dose directly to the tumor while substantially reducing the impact on adjacent normal organs. 64 Several prospective phase I and II studies have rigorously examined the efficacy and feasibility of CIRT for HCC. In a landmark 2004 phase I trial by the National Institute of Radiological Sciences in Japan, dose escalation from 49.5 Gy (relative biological effectiveness [RBE]) to 79.5 Gy (RBE) in 15 fractions exhibited no severe adverse effects or deaths, achieving an 81% local control rate at 3 and 5 years.…”

Novel paradigm in the treatment of hepatocellular carcinoma: Anticipating breakthroughs with particle therapy

“…Particle therapy that can be used in the management of HCC is mainly divided into proton beam therapy (PBT) and carbon ion RT (CIRT). 11,12 The main physical characteristics of particle therapy is the absorbed dose curve shows a slow initial increase with the penetration through matter, than a steep rise to the maximum, known as the Bragg peak, followed by a sharp fall in energy absorption toward the end of the beam range. 13 This unique characteristics can be able to provide a more precise dose delivery to the tumor, while minimizing radiation effect to the surrounding normal tissues effectively.…”