Clinical Application and Prospect of New Radiotherapy Technology in Cancer Treatment

Objective: Carbon ion therapy, a new radiotherapy technology, has shown its remarkable efficacy and potential in cancer treatment, especially in the treatment of refractory tumors. Methods: This paper clarifies the physical basis, technological change, and clinical practice effect of carbon ion therapy, comprehensively discusses the future prospects, and evaluates the clinical application effect. Results: The technology has significantly improved the treatment effectiveness and received a positive response from patients. Conclusion: Carbon ion therapy technology has become a major innovation in the field of cancer treatment. It not only has a profound impact on many current cancer therapy methods but also indicates the application blueprint for a wider range of cancer types in the future, showing a new chapter of medical technology advancement.

Neutron dose measurement in carbon ion radiation therapy at HIRFL(IMP)

For radiation protection purposes, the neutron dose in carbon ion radiation therapy at the HIRFL （Heavy Ion Research Facility in Lanzhou） was investigated. The neutron dose from primary ^12C ions with a specific energy of 100 MeV/u delivered from SSC was roughly measured with a standard Anderson-Broun rem-meter using a polyethylene target at various distances. The result shows that a maximum neutron dose contribution of 19 mSv in a typically surface tumor treatment was obtained, which is less than 1% of the planed heavy ion dose and is in reasonable agreement with other reports. Also the T-ray dose was measured in this experiment using a thermo luminescent detector.

The role of radiation therapy and particle therapy in renal cell carcinoma: current evidence and future perspectives

For both primary and metastatic renal cell carcinoma(RCC),treatment with stereotactic body radiotherapy(SBRT)has found its way into clinical practice.Being a non-invasive outpatient procedure,SBRT requires only a few visits to the radiation department and may be of interest for the elderly or,in the case of primary RCC,for patients who are not considered surgical candidates due to technical limitations,medical comorbidities,or in the event that the maintenance of kidney function is compromised.In the treatment landscape of oligometastatic RCC,SBRT shows promise in eradicating metastatic disease and delaying the initiation of systemic treatment.Technical advancements in the planning and administration of radiation treatment and improvements in movement management allow irradiating the tumor and/or metastatic lesions with very high doses in few fractions while maximally sparing the surrounding organs at risk,thus minimizing toxicity.In that context,the increasing availability of particle therapy,such as proton beam radiotherapy or carbon ion radiotherapy,could further optimize the delivery of radiation treatment in order to reduce toxicity and improve outcome.

Zinc-doped Prussian blue nanoparticles for mutp53-carrying tumor ion interference and photothermal therapy

Quite a great proportion of known tumor cells carry mutation in TP53 gene,expressing mutant p53 proteins(mutp53)missing not only original genome protective activities but also acquiring gain-of-functions that favor tumor progression and impede treatment of cancers.Zinc ions were reported as agents cytocidal to mutp53-carrying cells by recovering p53 normal functions and abrogating mutp53.Meanwhile in a hyperthermia scenario,the function of wild type p53 is required to ablate tumors upon heat treatment hence the effects might be hindered in a mutp53 background.We herein synthesized zinc-doped Prussian blue(ZP)nanoparticles(NPs)to combine Zn 2+based and photothermal therapeutic effects.An efficient release of Zn 2+in a glutathione-enriched tumor intracellular microenvironment and a prominent photothermal conversion manifested ZP NPs as zinc ion carriers and photothermal agents.Apoptotic death and autophagic mutp53 elimination were found to be induced by ZP NPs in R280K mutp53-containing MDA-MB-231 cells and hyperthermia was rendered to ameliorate the treatment in vitro through further mutp53 elimination and increased cell death.The combinatorial therapeutic effect was also confirmed in vivo in a mouse model.This study might expand zinc delivery carriers and shed a light on potential interplay of hyperthermia and mutp53 degradation in cancer treatment.

Experimental measurement of the correlation between CT number and heavy ion range

For precision delivery of the Bragg peak of a heavy-ion beam to a target volume in ion beam therapy, it is necessary to know the tissue stopping power. A general approach to solve this problem in ion beam therapy is to convert X-ray CT （computed tomography） numbers into water-equivalent path length （WEPL） coefficients using a CT-WEPL calibration curve for all voxels traversed by the beam. This work aims at establishing a CT-WEPL coefficient calibration curve for the heavy ion therapy project at IMP, so as to compute the range of carbon ion beams in tissues easily according to the patient CT data. Several tissueequivalent materials were applied to measure their WEPL coefficients using a high-energy carbon ion beam in this work. A CT-WEPL calibration curve was obtained through fitting the measured data, which can be used directly for dose optimization and facilitates the design of patient treatment plans significantly at IMP.