Targeted alpha therapy (TAT) has recently emerged as a highly promising approach for the management of metastatic castration-resistant prostate cancer (mCRPC), especially in patients with disease progression despite standard treatments. Among alpha-emitter radiopharmaceuticals, actinium-225-labelled prostate-specific membrane antigen ([225Ac]Ac-PSMA) has shown remarkable potential due to its high linear energy transfer (LET), short path length, and ability to induce potent, localised cytotoxic effects. This review summarises current clinical evidence regarding [225Ac]Ac-PSMA radioligand therapy (RLT), emphasising its efficacy, safety profile, and position relative to beta-emitter therapy with lutetium-177 ([177Lu]Lu-PSMA). Data from compassionate-use programs and small clinical trials demonstrate that [225Ac]Ac-PSMA produces significant biochemical and imaging responses, including > 50% declines in prostate-specific antigen (PSA) and lesion regression on [68Ga]Ga-PSMA PET/CT, even in heavily pre-treated mCRPC cohorts. Xerostomia, renal toxicity, and haematological adverse effects remain the main safety challenges, necessitating optimisation of patient selection, dosing strategies, and salivary gland protection protocols. Compared with [177Lu]Lu-PSMA, [225Ac]Ac-PSMA appears effective even in cases of beta-refractory disease, highlighting its complementary role rather than a competitive alternative. However, limited availability, high production costs, and the lack of large-scale, randomised trials hinder widespread clinical adoption. Future directions include combination protocols, improved radiopharmaceutical design, and trials evaluating its use in earlier disease stages. This review provides a comprehensive overview of the clinical aspects of [225Ac]Ac-PSMA RLT and its evolving role in advanced prostate cancer management.

Introduction: The purpose of the study was to compare the results of gamma value based film analysis according to the used type of self-developer film and software product. Material and methods: The films were irradiated with different treatment techniques such as 3D conformal and intensity modulated radiotherapy with static and rotational delivery. Stereotactic plans with conformal and intensity modulated arc techniques, using coplanar and non-coplanar beam setup were also evaluated. The data of irradiated film were compared with the planned planar dose distribution exported from the treatment planning system. Three film analysis software programs were evaluated: PTW Mephysto (PTW), FilmQA Pro (FQP) and radiohromic.com(RC). Both EBT2 and EBT3 types of films were examined. The comparisons of dose distributions were performed with gamma analysis using 10% cut-off level. Results: The results of the gamma analysis for larger fields were between 78.3% and 98.3%, 75.7% and 100%, 80.2% and 98.8% with PTW, FQP and RC, respectively. The results of evaluation in case of stereotactic measurements were 76.8%–99.2% for PTW, 95.7%–100% for FQP and 91.2%–99.9% for RC. Conclusions: All the three software programs are suitable for calibrating and evaluating films, performing gamma analysis, and can be used for patient specific quality assurance measurements. There is no direct connection between gamma passing rate and absolute accuracy or software quality, it is just a feature of the software. The interpretation of own results has to be defined on an institutional level according to given workflow and preliminary results.

Objective. For quality assurance purposes, one must apply an axial scanning geometry to verify the displayed CT dose index (CTDI) value. This is usually unavailable on newer machines. The multiple scan average dose (MSAD) method was proposed earlier to circumvent this issue, but has not become widespread. Approach. Monte Carlo simulation was combined with its analytical postprocessing to accurately calculate scattering and speed up calculations to investigate several imaging and beam parameter combinations. The calculations were validated by measurements, and the model was used to examine the uncertainty of MSAD caused by an uncontrolled parameter. Main results. By utilizing the periodicity of the MSAD measurement, the uncertainty can be reduced to 0.2%, in contrast to 26.4% in the worst case. The widespread 150 mm long CTDI phantom and the 100 mm long ionization chamber are applicable for the MSAD method and reach 81% efficiency in the estimation of CTDIvol, in contrast to 78% efficiency of the CTDI100 method. Significance. The MSAD measurement with the CTDI setup is slightly more efficient than the CTDI100 measurement protocol. Furthermore, it is applicable both for helical and axial scans, so we recommend the use of direct MSAD measurement for quality assurance in the clinical environment.