ABSTRACT
Technological advances in radiation oncology are oriented towards improving treatment precision and tumor control. Among these advances, magnetic-resonance-image-guided radiation therapy (MRgRT) stands out, with technological advances to deliver targeted treatments adapted to a tumor's anatomy on the day while minimizing incidental exposure to organs at risk, offering an unprecedented therapeutic advantage compared to X-ray-based IGRT delivery systems. This new technology changes the traditional workflow in radiation oncology and requires an evolution in team coordination to administer more precise treatments. Once implemented, it paves the way for newer indication for radiation therapy to safely deliver higher doses than ever before, with better preservation of healthy tissues to optimize patient outcomes. In this narrative review, we assess the technical aspects of the novel linear accelerators that can deliver MRgRT and summarize the available published experience to date, focusing on oncological results and future challenges.
ABSTRACT
This observational, descriptive, longitudinal, and prospective basket-type study (Registry #5289) prospectively evaluated the feasibility and acute toxicity of hypo-fractionated radiotherapy on the first 0.35T MR-LINAC in Spain. A total of 37 patients were included between August and December 2023, primarily with prostate tumors (59.46%), followed by pancreatic tumors (32.44%). Treatment regimens typically involved extreme hypo-fractionated radiotherapy, with precise dose delivery verified through quality assurance measures. Acute toxicity assessment at treatment completion revealed manageable cystitis, with one case persisting at the three-month follow-up. Gastrointestinal toxicity was minimal. For pancreatic tumors, daily adaptation of organ-at-risk (OAR) and gross tumor volume (GTV) was practiced, with median doses to OAR within acceptable limits. Three patients experienced gastrointestinal toxicity, mainly nausea. Overall, the study demonstrates the feasibility and safety of extreme hypo-fractionated radiotherapy on a 0.35T MR-LINAC, especially for challenging anatomical sites like prostate and pancreatic tumors. These findings support the feasibility of MR-LINAC-based radiotherapy in delivering precise treatments with minimal toxicity, highlighting its potential for optimizing cancer treatment strategies.
ABSTRACT
Radical prostatectomy (RP) is one of the primary treatment options for localised prostate cancer (PCa). Despite its curative intent, 1/3 of patients will experience biochemical recurrence (BCR) during follow-up. Experts have devoted efforts to associate the influence of each individual factor with the risk of BCR to select the optimal treatment for each patient. Optimal management must aim to find a balance between delaying the onset of metastatic disease and overtreating an indolent disease with treatments that can affect quality of life of the patients. Thus far, effective treatment options for men with BCR remain controversial in terms of ideal treatment timing (adjuvant vs. salvage), radiotherapy (RT) fields and doses, selection and duration of systemic therapy and potential synergies between treatments and their therapeutic sequencing. Next-generation imaging techniques, such as Prostate-Specific Membrane Antigen Positron Emission Tomography, are used for early detection of disease progression and exact site of recurrence or progression, thereby enhancing decision making for future disease management. In this review, we evaluate available evidence of controversial topics regarding BCR after RP and explore future directions, such as prognostic and/or predictive factors of response, genetic panels, second-generation hormone treatments, ultra-hypofractionated RT and ongoing clinical trials in this clinical scenario.