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Abstract Glioblastoma is an aggressive brain cancer with a poor prognosis. The O6-methylguanine-DNA methyltransferase (MGMT) gene methylation status is crucial for treatment stratification, yet economic constraints often limit access. This study aims to develop an artificial intelligence (AI) framework for predicting MGMT methylation. Diagnostic magnetic resonance (MR) images in public repositories were used for training. The algorithm created was validated in data from a single institution. All images were segmented according to widely used guidelines for radiotherapy planning and combined with clinical evaluations from neuroradiology experts. Radiomic features and clinical impressions were extracted, tabulated, and used for modeling. Feature selection methods were used to identify relevant phenotypes. A total of 100 patients were used for training and 46 for validation. A total of 343 features were extracted. Eight feature selection methods produced seven independent predictive frameworks. The top-performing ML model was a model post-Least Absolute Shrinkage and Selection Operator (LASSO) feature selection reaching accuracy (ACC) of 0.82, an area under the curve (AUC) of 0.81, a recall of 0.75, and a precision of 0.75. This study demonstrates that integrating clinical and radiotherapy-derived AI-driven phenotypes can predict MGMT methylation. The framework addresses constraints that limit molecular diagnosis access.

Purpose: To develop a specialist-based consensus of cochlear contouring to be used in patients undergoing stereotactic radiosurgery (SRS) treatment for vestibular schwannoma. Methods and Materials: Representative computed tomography (CT) and magnetic resonance imaging (MRI) were used for cochlear contouring. The semicircles, cochlea, vestibule, and internal acoustic meatus were delineated by 7 radiation oncology department physicians and reviewed by neuroradiologists. A total of 12 cases accrued from a single academic institution were studied for a similarity analysis by the Dice coefficient. Results: The suggested guideline is an easily reproductive tool that allows radiation oncologists to accurately contour the vestibulocochlear system to avoid toxicity due to inadequate dosimetry of organs at risk. This could be a useful tool even for non-vestibular schwannoma radiation therapy. The Dice coefficient suggests reproducible results as long as the following contouring recommendations are observed. Conclusions: The template for vestibulocochlear delineation may be useful for an adequate organs at risk definition. Future studies are required to find specific constraints for each segment of the vestibulocochlear system, and to mitigate interobserver variations.

Summary: Background: The Radiotherapy Expansion Plan for Brazil's Unified Health System (PER-SUS) was an innovative program designed by the Ministry of Health in 2012 to provide improvements to the challenging problem of access to radiotherapy in the country. This study sought to analyze the execution and implementation of installations proposed by PER-SUS, and their capacity to address the problems of radiotherapy access in Brazil. Methods: From the first release (February 2015) until October 2021, all PER-SUS monthly progress reports were retrospectively analyzed. The beneficiary institutions, project location, project status, project type, dates of the progress on the stages, and reasons for cancellations or possible justifications for changing the status were collected. Brazilian geographic data, health care demands, and cancer incidences were correlated. Finally, we performed an Ishikawa diagram and 5W3H methodology, aiming to better understand the findings and to yield possible ways to improve the access to radiotherapy. Findings: After ten years, the PER-SUS project delivered nearly 50% of the planned implementation of radiotherapy equipment. There was a 17% growth in the national number of linear accelerators (LINACS) with PER-SUS, against a 32% increase in cancer incidence in Brazil in the same period. The following points were identified: a high rate of beneficiary exclusions reflecting inappropriate selection or inadequate planning; delays in execution related to bureaucratic obstacles and underestimation of the requirements (logistics/people); early closing of the equipment factory as a result of lack of project prioritization by the Government. Interpretation: Only about 50% of PER-SUS are being carried out. However, delays and exclusions of beneficiaries were observed. The dimension of the need for radiotherapy care in Brazil is greater than considered, and might not be fully attended by PER-SUS. Geographic, epidemiological, logistical, and economic variables could be reevaluated to allow better strategic planning and improvement proposals. PER-SUS could be optimized for the next decade, by involving all stakeholders' participation, alignment, and engagement. In the future, the States and regions with a higher LINAC shortage should be prioritized to improve RT access across the country. Considering the data and the initial project deadline, PER-SUS did not achieve the pre-established goals specified by the Brazilian Government. Funding: This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Background: The majority of patients diagnosed with glioblastoma develop recurrent disease resulting in poor prognoses. The current study aimed to determine the survival rates of patients diagnosed with glioblastoma in Brazil accounting for the influence of age, treatment modalities, public and private practices, and educational level using a population-based national database. Methods: Patients diagnosed with glioblastoma from 1999-2020 were identified from The Fundação Oncocentro de São Paulo database to create a retrospective cohort. Patients were described according to age, education level treatment modalities and medical practice. In a Cox proportional hazards model, controlled for confounding factors for overall survival, the hazard ratio and 95% CI of overall survival in adults was evaluated. Findings: A total of 4,511 patients were included. The median lengths of survival for patients treated in the public and private settings were 8 and 17 months (p

We undertook a structured review of stereotactic radiosurgery (SRS) using linear particle accelerator (linac) equipment, focusing on volumetric modulated arc therapy (VMAT) technology, and frameless image-guided radiotherapy (IGRT), for the treatment of brain metastases. We analyzed the role of linac SRS and its clinical applications, exploring stereotactic localization. Historically, there was a shift from fixed frames to frameless approaches, moving toward less invasive treatments. Thus, we reviewed the concepts of VMAT for multiple-target applications, comparing its dosimetric and technical features to those of other available techniques. We evaluated relevant technical issues and discussed the planning parameters that have gained worldwide acceptance to date. Thus, we reviewed the current literature on the clinical aspects of SRS, especially its main indications and how the advantages of VMAT may achieve clinical benefits in such scenarios. Finally, we reported our institutional results on IGRT-VMAT for SRS treatments for patients with multiple brain metastases.

Many cancer patients will develop spinal metastases. Local control is important for preventing neurologic compromise and to relieve pain. Stereotactic body radiotherapy or spinal radiosurgery is a new radiation therapy technique for spinal metastasis that can deliver a high dose of radiation to a tumor while minimizing the radiation delivered to healthy, neighboring tissues. This treatment is based on intensity-modulated radiotherapy, image guidance and rigid immobilization. Spinal radiosurgery is an increasingly utilized treatment method that improves local control and pain relief after delivering ablative doses of radiation. Here, we present a review highlighting the use of spinal radiosurgery for the treatment of metastatic tumors of the spine. The data used in the review were collected from both published studies and ongoing trials. We found that spinal radiosurgery is safe and provides excellent tumor control (up to 94% local control) and pain relief (up to 96%), independent of histology. Extensive data regarding clinical outcomes are available; however, this information has primarily been generated from retrospective and nonrandomized prospective series. Currently, two randomized trials are enrolling patients to study clinical applications of fractionation schedules spinal Radiosurgery. Additionally, a phase I clinical trial is being conducted to assess the safety of concurrent stereotactic body radiotherapy and ipilimumab for spinal metastases. Clinical trials to refine clinical indications and dose fractionation are ongoing. The concomitant use of targeted agents may produce better outcomes in the future.

Introduction. Chordomas are rare malignancies of bone origin that occur in the axial skeleton, typically the skull base and lumbar/sacral regions. Although often classified as low-grade neoplasms, its locally infiltrative behavior may result in significant morbidity and mortality. Optimal surgical resection may be curative, but up to 50% of the cases relapse within 5 years, and currently there are no systemic treatments approved in this setting. A large proportion of these tumors express stem-cell factor receptor (c-KIT) and platelet-derived growth factor receptors (PDGFRs), providing a rationale for the use of tyrosine-kinase inhibitors (TKIs). Case report. A 27-year-old male presented with recurrent chordoma of the lumbar spine 4 years after initial diagnosis. Salvage therapies in the interval included repeat resections and radiation therapy. He ultimately developed multifocal recurrence not amenable to complete excision or reirradiation. A comprehensive genomic profiling assay was performed and revealed nondrugable alterations. Decision was made to proceed with systemic treatment with pazopanib 800 mg/day, resulting in tumor reduction (−23.1% reduction in size) and prolonged disease control. Conclusion. For this patient with a multiple recurrent chordoma and limited treatment options, pazopanib resulted in sustained clinical benefit following initial tumor reduction.

Introduction Brachytherapy is an option for treating low-risk prostate cancer (PC). Biochemical control of low-risk disease can reach 95%. The practice advocated is that a review of prostate biopsies should be mandatory before choosing the best treatment for patients with PC. Our objective was to evaluate the change in PC risk after review of a prostate biopsy by an experienced uropathologist at a reference hospital. Materials and Methods Between December 2003 and August 2012, 182 men were referred to our institution for brachytherapy to treat PC. Their slides were reviewed by the same uropathologist. Results and Discussion Classification risk disagreement occurred in 71 (39%) cases, including one in which no tumor was observed. The main cause of risk change was related to the Gleason score (GS), with 57 (81.4%) cases upgraded to GS 7 or 8. Tumor volume was also compared, although only the number of fragments was reported in most original reports. The concordance of the number of cores affected by tumor was 43.9%, and in 49% of the cases, the number was decreased by the uropathologist. Perineural invasion (PNI) was reported in one quarter of original reports, and the agreement was 58%. Conclusion Slide review by an uropathologist remains essential at reference radiotherapy centers for the treatment of PC. The change in PC risk evaluation is mainly due to the GS, but tumor volume and PNI, which are important for the characterization of tumor aggressiveness, are also misinterpreted and could drive a change in the therapy choice.

The role of radiotherapy (RT) in the treatment of urinary bladder cancer has undergone several modifications along the last decades. In the beginning, definitive RT was used as treatment in an attempt to preserve the urinary bladder; however, the results were poor compared to those of radical surgery. Recently, many protocols have been developed supporting the use of multi-modality therapy, and the concept of organ preservation began to be reconsidered. Although phase III randomized clinical studies comparing radical cystectomy with bladder preservation therapies do not exist, the conservative treatment may present low toxicity and high indexes of complete response for selected patients. The aim of this study was to review the literature on the subject in order to situate RT in the current treatment of urinary bladder cancer.

Micose fungoide é um tipo de linfoma não Hodgkin de células T raro que acomete primariamente a pele. Caracteriza-se pela presença de placas eritematosas que evoluem para lesões ulceradas, tumores em toda a pele ou ainda infiltração de medula óssea em estágios avançados. Como opção de tratamento para os casos iniciais, tem-se quimioterapia e corticoterapia tópica, fototerapia e radioterapia. Este estudo relata o caso de um doente com múltiplas lesões tumorais na pele já biopsiadas com diagnóstico de micose fungoide. O paciente foi refratário ao tratamento com quimioterapia tópica e fototerapia, sendo então indicada irradiação total da pele com elétronsMycosis fungoides is a rare type of non-Hodgkin's lymphoma of T cells that primarily affects the skin. It is characterized by the presence of erythematous plaques that evolve into ulcerated lesions, tumors throughout the skin or even bone marrow infiltration in advanced stages. Chemotherapy and topical steroids, phototherapy and radiotherapy are treatment options for early cases. This study reports the case of patient with multiple tumor lesions in the skin already biopsied with diagnosis of mycosis fungoides. The patient was refractory to both treatments with topical chemotherapy and phototherapy. It was then indicated total skin irradiation with electrons

CONTEXT AND OBJECTIVE: To the best of our knowledge, there has been no systematic assessment of the classification of scientific production within the scope of radiation oncology relating to central nervous system tumors. The aim of this study was to systematically assess the status of evidence relating to the central nervous system and to evaluate the geographic origins and major content of these published data.DESIGN AND SETTING: Descriptive critical appraisal study conducted at a private hospital in São Paulo, Brazil.METHODS: We evaluated all of the central nervous system studies published in the journal Radiotherapy & Oncology between 2003 and 2012. The studies identified were classified according to their methodological design and level of evidence. Information regarding the geographical location of the study, the institutions and authors involved in the publication, main condition or disease investigated and time of publication was also obtained.RESULTS: We identified 3,004 studies published over the 10-year period. Of these, 125 (4.2%) were considered eligible, and 66% of them were case series. Systematic reviews and randomized clinical trials accounted for approximately 10% of all the published papers. We observed an increase in high-quality evidence and a decrease in low-quality published papers over this period (P = 0.036). The inter-rater reliability demonstrated significant agreement between observers in terms of the level of evidence.CONCLUSIONS: Increases in high-level evidence and in the total number of central nervous system papers were clearly demonstrated, although the overall number of such studies remained relatively small.