Advanced Radiotherapy Techniques Research Articles

Clinical Biomarkers of Tumour Radiosensitivity and Predicting Benefit from Radiotherapy: A Systematic Review.

Modern advanced radiotherapy techniques have improved the precision and accuracy of radiotherapy delivery, with resulting plans being highly personalised based on individual anatomy. Adaptation for individual tumour biology remains elusive. There is an unmet need for biomarkers of intrinsic radiosensitivity that can predict tumour response to radiation to facilitate individualised decision-making, dosing and treatment planning. Over the last few decades, the use of high throughput molecular biology technologies has led to an explosion of newly discovered cancer biomarkers. Gene expression signatures are now used routinely in clinic to aid decision-making regarding adjuvant systemic therapy. They have great potential as radiotherapy biomarkers. A previous systematic review published in 2015 reported only five studies of signatures evaluated for their ability to predict radiotherapy benefits in clinical cohorts. This updated systematic review encompasses the expanded number of studies reported in the last decade. An additional 27 studies were identified. In total, 22 distinct signatures were recognised (5 pre-2015, 17 post-2015). Seventeen signatures were 'radiosensitivity' signatures and five were breast cancer prognostic signatures aiming to identify patients at an increased risk of local recurrence and therefore were more likely to benefit from adjuvant radiation. Most signatures (15/22) had not progressed beyond the discovery phase of development, with no suitable validated clinical-grade assay for application. Very few signatures (4/17 'radiosensitivity' signatures) had undergone any laboratory-based biological validation of their ability to predict tumour radiosensitivity. No signatures have been assessed prospectively in a phase III biomarker-led trial to date and none are recommended for routine use in clinical guidelines. A phase III prospective evaluation is ongoing for two breast cancer prognostic signatures. The most promising radiosensitivity signature remains the radiosensitivity index (RSI), which is used to calculate a genomic adjusted radiation dose (GARD). There is an ongoing phase II prospective biomarker-led study of RSI/GARD in triple negative breast cancer. The results of these trials are eagerly anticipated over the coming years. Future work in this area should focus on (1) robust biological validation; (2) building biobanks alongside large radiotherapy randomised controlled trials with dose variance (to demonstrate an interaction between radiosensitivity signature and dose); (3) a validation of clinical-grade cost-effective assays that are deliverable within current healthcare infrastructure; and (4) an integration with biomarkers of other determinants of radiation response.

National pilot-study on verification of calculated absorbed dose distribution to be delivered in advanced radiotherapy treatment

Dosimetry audits in radiation oncology are indicated in the Council Directive 2013/59/EURATOM as one of several measures to ensure high quality of absorbed dose delivery in radiation therapy. Therefore, a national pilot-study was prepared and conducted for an on-site dosimetry audit on the 2D pre-treatment verification methodology. The aim was to explore the possibility of introducing such audits at the national level and examine the feasibility of extending such a concept.The main activities performed were developing and verifying methodology to be applied elsewhere, assembling a survey related to the application of advanced radiotherapy techniques, point and 2D absorbed dose measurements, and acquiring data for on-site and off-site data validation. The measurements of 2D absorbed dose distributions of different complexities were performed using local and auditor's (reference) equipment. The beam output, dose linearity, and field output factors were determined using a reference set of equipment only.Eight high-energy photon beams were evaluated. The participating centres fulfilled the recommended criterion of ±2% for beam output. Seven beams fulfilled the dose linearity criterion. Comparison of field output factors exhibited out-of-tolerance discrepancies only for the smallest field size of 2 × 2 cm2.For the evaluation of 2D absorbed dose distributions, the results obtained with local equipment showed that all absorbed dose distributions had gamma (γ) passing rate ≥95% for the 3%/2 mm tolerance criterion. However, the γ passing rates obtained with the reference equipment were lower for most verified beams. Some of the analysed absorbed dose distributions did not fulfil the recommended γ passing rate acceptance criterion. γ passing rates have shown a statistically significant difference for 3%/2 mm and 2%/2 mm criteria with p = 0.0117 and p = 0.0212, respectively, comparing the results obtained by reference and local equipment.External audits related to the 2D dosimetrical pre-treatment verification of calculated dose distributions provide the advantage of being independent of the equipment and methodology used locally. Such audits can be a valuable tool for the evaluation and improvement of local practices in the application of advanced radiotherapy techniques.

Radiotherapy Related Bowel and Bladder Toxicity after Prostate Cancer Irradiation

Background: Pelvic radiotherapy is a primary treatment modality for organ-confined prostate cancer and early-stage endometrial cancer. While effective in improving survival rates and reducing recurrence, it is associated with a range of side effects that can impact patient quality of life. Objective: The study aimed to assess the incidence, management, and resolution of acute and chronic side effects of pelvic radiotherapy in prostate and endometrial cancer patients, focusing on bowel and bladder functions. Methods: This single-center, observational study included 50 patients diagnosed with prostate or endometrial cancer who underwent pelvic radiotherapy with a dose of 66-70 Gy using a four-field technique on a linear accelerator. Patients were assessed for bladder and bowel dysfunction, with follow-up at 6, 12, and 18 months post-treatment. Statistical analysis involved univariate weighted distribution of response frequencies and paired t-tests for ordinal scale scores, using SPSS version 25 for data analysis. Results: Of the participants, 22% experienced dysuria, 64% reported bladder outlet obstruction, and 20% had constipation. Acute bowel symptoms like diarrhea occurred in 32%, and chronic proctitis developed in 22% of patients. Urinary symptoms appeared by the third week and generally resolved within weeks; however, bowel symptoms persisted longer but returned to baseline by 18 months post-treatment. Approximately 70% of patients reported good tolerance to radiotherapy. Conclusion: Pelvic radiotherapy is effective in treating prostate and endometrial cancers but requires management of transient side effects to improve patient outcomes. Advanced radiotherapy techniques such as IMRT and 3D CRT have shown potential in reducing these side effects, emphasizing the need for continuous technological advancements and patient-centered care in radiotherapy.

Treatment Related Acute Toxicities Between Treatment with 3D-CRT and IMRT in Localised Prostate Cancer.

To compare the acute toxicities of two radiation treatment techniques, intensity modulated radiation therapy (IMRT), and 3-dimensional conformal radiation therapy (3D-CRT) in localised prostate adenocarcinoma. Descriptive study. Place and Duration of the Study:Department of Oncology, Dr. Ziauddin Hospital, Karachi, Pakistan, from July 2016 to June 2022. Patients with localised prostate adenocarcinoma who underwent treatment using two different advanced radiotherapy techniques i.e., IMRT and 3D-CRT were recruited during the study period. They were followed up for six months for acute gastrointestinal (GI) and genitourinary (GU) adverse events (acute toxicities) related to both treatment modalities according to Modified radiation therapy oncology group (RTOG) criteria. The acute toxicities were assessed at the 2nd, 4th, and 6th week during treatment and at the 3rd and 6th month after treatment. There were 78 patients, with 39 patients in each group. The mean age was 68 ± 10 years in the 3D-CRT and 68 ± 07 years in the IMRT group. Patients in the IMRT group exhibited markedly lower treatment-related acute GI and GU effects at the end of 4th and 6th weeks for anorectal pain (p = 0.04) and (p = 0.01) and burning micturition (p = 0.003) and (p = 0.01), respectively. Furthermore, at 3 months anorectal pain (p = 0.02), loose stools (p = 0.005), and burning micturition (p = 0.01) were present and at 6 months anorectal pain was (p = 0.01) still present. Radiation therapy modalities 3D-CRT and IMRT both showed acceptable toxicity profile in the management of localised prostate cancer, while IMRT group exhibited significantly lower treatment-related acute GI and GU effects. 3D-CRT (3-Dimensional Conformal Radiation Therapy), IMRT (Intensity-Modulated Radiation Therapy), Radiation toxicity.

Dosimetric comparison of advanced radiation techniques for scalp-sparing in low-grade gliomas.

Alopecia causes significant distress for patients and negatively impacts quality of life for low-grade glioma (LGG) patients. We aimed to compare and evaluate variations in dose distribution for scalp-sparing in LGG patients with proton therapy and photon therapy, namely intensity-modulated proton therapy (IMPT), intensity-modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT), and helical tomotherapy (HT). This retrospective study utilized adataset comprising imaging data from 22patients with LGG who underwent postoperative radiotherapy. Treatment plans were generated for each patient with scalp-optimized (SO) approaches and scalp-non-optimized (SNO) approaches using proton techniques and photons techniques; all plans adhered to the same dose constraint of delivering atotal radiation dose of 54.04 Gy to the target volume. All treatment plans were subsequently analyzed. All the plans generated in this study met the dose constraints for the target volume and OARs. The SO plans resulted in reduced maximum scalp dose (Dmax), mean scalp dose (Dmean), and volume of the scalp receiving 30 Gy (V30) and 40 Gy (V40) compared with SNO plans in all radiation techniques. Among all radiation techniques, the IMPT plans exhibited superior performance compared to other plans for dose homogeneity as for SO plans. Also, IMPT showed lower values for Dmean and Dmax than all photon radiation techniques. Our study provides evidence that the SO approach is afeasible technique for reducing scalp radiation dose. However, it is imperative to conduct prospective trials to assess the benefits associated with this approach.

Study of PRESAGE® dosimeter for end-to-end 3D radiotherapy verification using an anthropomorphic phantom with bespoke dosimeter insert.

Modern radiotherapy techniques have advanced and become more sophisticated. End-to-end 3D verification of the complex radiotherapy dose distribution in an anthropomorphic phantom can ensure the accuracy of the treatment delivery. The phantoms commonly used for dosimetry are homogeneous solid water phantom which lacks the capability to measure the 3D dose distribution for heterogeneous tissues necessary for advanced radiotherapy techniques. Therefore, we developed an end-to-end 3D radiotherapy dose verification system based on MAX-HD anthropomorphic phantom (Integrated Medical Technologies Inc., Troy, New York) with bespoke intracranial insert for PRESAGE® dosimeter. In this study, several advanced radiotherapy treatment techniques of various levels of complexity; 3D-CRT, IMRT and VMAT treatment, were planned for a 20mm diameter of a spherical target in the brain region and delivered to the phantom. The dosimeters were read out using an in-house developed optical computed tomography (OCT) imaging system known as 3DmicroHD-OCT. It was found that the measured dose distribution of the PRESAGE® when compared with the measured dose distribution of EBT film and Monaco TPS has a maximum difference of less than 3% for 3D-CRT, IMRT and VMAT treatment plans. The gamma analysis results of PRESAGE® in comparison to EBT film and Monaco TPS show pass rates of more than 95% for the criteria of 3% dose difference and 3mm distance-to-agreement. This study proves the capability of PRESAGE® and bespoke MAX-HD phantom in conjunction with the 3DmicroHD-OCT system to measure 3D dose distribution for end-to-end dosimetry verification.

Technical advances in radiotherapy in cancer management “Hobson’s choice or horned dilemma”

Technical advances in radiotherapy in cancer management “Hobson’s choice or horned dilemma”

DOSIMETRIC COMPARISON OF INTENSITY-MODULATED RADIATION THERAPY (IMRT) AND VOLUMETRIC-MODULATED ARC THERAPY (VMAT) IN RECTAL CANCER PATIENTS: A COMPREHENSIVE ANALYSIS

This study aimed to conduct a thorough dosimetric comparison between two advanced radiotherapy techniques, Intensity-Modulated Radiation Therapy (IMRT) and Volumetric-Modulated Arc Therapy (VMAT), to ascertain the superior modality in terms of dose distribution and organ-at-risk sparing for rectal cancer patients. Thirty-three patients with ECOG performance status 1, aged between 18 to 60 years, diagnosed with Stage II to III rectal cancer, were included in this prospective study. Each patient underwent treatment planning with IMRT and VMAT techniques using Varian system simulation computed tomography scans. The dosimetric analysis encompassed the evaluation of target volume dose homogeneity, conformity, and doses to at-risk organs. The dosimetric comparison was conducted utilizing seven-field IMRT and dual arc VMAT plans. Statistical analysis was performed using paired t-tests and SPSS 20 software. Treatment plan constraints adhered to the RTOG 9406 guidelines, ensuring adequate planning target volume (PTV) coverage, homogeneity index, conformity index, and dose limits for organs at risk, including small bowel V20 (<200cc), bladder V45 (<21Gy), and femoral head V50 (≤30 Gy). Volumetric arc therapy plans demonstrated superior dose homogeneity to fixed-field intensity-modulated plans (p-value = 0.04), particularly in femoral head dose-limiting toxicity (p-value = 0.00). However, intensity-modulated therapy exhibited equivalent or superior performance in other evaluated parameters. Our findings suggest that while VMAT offers advantages in PTV coverage homogeneity and femoral head dose-limiting toxicity, IMRT remains competitive and potentially preferable in certain dosimetric aspects. The choice between IMRT and VMAT should be carefully considered based on individual patient characteristics and treatment goals. This comprehensive dosimetric comparison contributes valuable insights into optimizing radiotherapy planning for rectal cancer patients, potentially guiding clinical decision-making and improving treatment outcomes.

The Accessible Clinical Application Progress of Supine Fixation Technique in Radiotherapy After Breast Conserving Surgery for Early Breast Cancer in China

Radiation therapy (radiotherapy) is one of the important methods for comprehensive treatment of breast cancer. Radiotherapy after breast conserving surgery for early breast cancer can not only achieve local control rate and long-term survival rate similar to total mastectomy, but also meet patients' pursuit of higher quality of life. With the development of intensity modulated radiotherapy (IMRT), volumetric modulated arc therapy (VMAT), helical tomotherapy (HT), and other advanced radiotherapy technique, the consistency of patient position fixation during radiotherapy is the key to ensure the implementation of accurate radiotherapy. Due to the special and high activity of breast organs, there is no unified fixation method for breast conserving postoperative radiotherapy. This article reviews the clinical application and research progress of various accessible supine fixation techniques in early breast cancer postoperative radiotherapy in recent years. This paper analyzes the clinical application method and clinical application effect of various techniques, compares the advantages and disadvantages of each technology. It is found that breast bracket is the most widely used for classical breast cancer radiotherapy. In any fixation technique, it is still a practical problem for the clinic to solve the problem of the normal location of the breast activity and the consistency of the radiation. It is recommended that the position of the supposition fixation technique should be selected according to the patient's BMI, breast size and target area.

The proton arc therapy treatment planning problem is NP-Hard

Proton arc therapy (PAT) is an advanced radiotherapy technique using charged particles in which the radiation device rotates continuously around the patient while irradiating the tumor. Compared to conventional, fixed-angle beam delivery mode, proton arc therapy has the potential to further improve the quality of cancer treatment by delivering accurate radiation dose to tumors while minimizing damage to surrounding healthy tissues. However, the computational complexity of treatment planning in PAT raises challenges as to its effective implementation. In this paper, we demonstrate that designing a PAT plan through algorithmic methods is a NP-hard problem (in fact, NP-complete), where the problem size is determined by the number of discrete irradiation angles from which the radiation can be delivered. This finding highlights the inherent complexity of PAT treatment planning and emphasizes the need for efficient algorithms and heuristics to address the challenges associated with optimizing the delivery of radiation doses in this context.

An Evaluation of Treatment Outcomes and Associated Factors in Nasopharyngeal Cancer Patients at a Tertiary Cancer Center in the United Arab Emirates.

Background and objective Nasopharyngeal carcinoma (NPC) presents a complex epidemiological pattern influenced by demographic characteristics, risk factors such as Epstein-Barr virus (EBV) infection, and smoking. Understanding the clinical profile and optimizing treatment strategies for NPC requires comprehensive analyses of these factors. In light of this, this study aimed to analyze the epidemiological patterns, histological characteristics, and treatment outcomes of NPCpatients diagnosed and treated at a single center from 2016 to 2023. Materials and methods This retrospective study was conducted at Tawam Hospital in the United Arab Emirates (UAE), focusing on patients diagnosed with NPC.It involved the analysis of patient age distribution to identify epidemiological patterns, histological examination to classify NPC types according to WHO guidelines, and evaluation of treatment outcomes based on induction chemotherapy regimens and concurrent chemoradiotherapy protocols. The effectiveness of various chemotherapy combinations, particularly cisplatin and 5-fluorouracil (Cis+5FU), was assessed alongside the integration of advanced radiotherapy techniques like intensity-modulated radiotherapy (IMRT). Results In this study of 41 NPC patients, the age distribution varied widely, ranging from 10 to 74 years, with a mean age of >40 years. There was a significantmale predominance (82.93%). Most patients were non-smokers (68.29%) and did not consume alcohol (92.68%), and there was a high prevalence of EBV positivity (100%). At diagnosis, 80.49% had no metastases. The primary treatment was chemotherapy induction, with a 73.17% uptake and a 92.68% completion rate, leading to a 65.85% complete response (CR) rate. No significant association was found between smoking status and treatment response (p=0.7657). Pathologically, non-keratinizing undifferentiated squamous carcinoma was the most common variant (75.61%). The Cis+5FUregimen was the most frequently employed method (56.67%), associated with a 76.47% CR rate. Concurrent chemotherapy was administered to 87.80% of patients, with the weekly Cis regimen being the most used one (56.09%), resulting in a significant CR rate. Combining radiation therapy with concurrent and induction chemotherapy yielded high CR rates (RT+cCT: 66.66%, RT+cCT+iCT: 80%). Survival analysis revealed the highest 36-month survival rate (46.43%) in the RT+cCT+iCT group, suggesting a potential benefit from incorporating induction chemotherapy into the treatment regimen. Conclusions This study illustrates the impact of demographic variables, EBV infection, and smoking on the development and treatment outcomes of NPC. It points to the success of customized chemotherapy and advanced radiotherapy strategies. Yet, it is limited by its retrospective nature and single-center focus, and hence we recommend multicentric studies to broaden the applicability of the results and improve NPC treatment approaches for varied patient groups.

Mogućnosti radioterapije u lečenju pedijatrijskog Hočkinovog limfoma

Pediatric Hodgkin lymphoma is a malignant, lymphoproliferative disease of children and adolescents. Radiotherapy is an important form of treatment. The possibility of late toxicity of radiotherapy is a limiting factor in the application of radiotherapy as a treatment modality in pediatric patients. The technological progress of radiotherapy and the introduction of advanced radiotherapy techniques and proton therapy have improved the precision of radiotherapy and reduced the risk of long-term consequences. These technologies enabled targeted treatment, significantly reducing the exposure of healthy tissues and organs to radiation. All existing treatment recommendations and conducted cooperative studies have shown that radiation therapy is effective in the treatment of pediatric Hodgkin lymphoma, especially when combined with chemotherapy. On the other hand, there is the possibility of late toxicity to organs in growth and development, as well as the possibility of occurrence of secondary malignancies, which must be carefully considered when deciding on the implementation of radiotherapy. Radiation therapy represents an important therapeutic approach in the combined treatment of pediatric Hodgkin lymphoma. The combined therapeutic approach has improved treatment results, and advanced radiotherapy techniques will reduce the risk of side effects. Indications for the use of radiotherapy should be carefully evaluated in the treatment of pediatric patients with Hodgkin lymphoma.

Knowledge, attitude, and practice toward advanced precision radiotherapy among patients with head and neck cancer.

Advancements in radiotherapy (RT) technology have led to the prominence of precision RT in head and neck cancer (HNC) treatment. The new progress in precision RT offers more efficient therapy, potentially improving outcomes for HNC patients. The present cross-sectional study aimed to assess the knowledge, attitude, and practice (KAP) of patients in advanced precision RT for HNC treatment. This study enrolled HNC patients at the Affiliated Hospital of Hebei University of Engineering between October 2023 and May 2024. Then, the demographic data and KAP scores were collected using an investigator-designed questionnaire. Afterwards, descriptive statistics were provided for all study variables, and the relationship among KAP was analyzed using appropriate statistical tests, including Spearman correlation, logistic regression, and path analysis. A total of 436 participants with a mean age of 52.03 ± 12.19 years old were included. The mean knowledge score, attitude score, and practice score were 18.33 ± 4.21, 36.14 ± 1.71, and 26.26 ± 1.83, respectively. Although most of the participants were unfamiliar with advanced precision RT, they expressed a high willingness to follow their doctor's recommendation for this treatment. The multivariable analysis revealed a positive association between attitude score and proactive practice. The path analysis revealed that knowledge directly influenced attitude and practice, while attitude directly impacted practice. HNC participants had poor knowledge of advanced precision RT techniques, but had a positive attitude and the willingness to undergo treatment when recommended by their physicians. These results suggest that improving patients' awareness for advanced precision RT can help to promote better attitude and advanced precision RT practice.

Structure regulation and synchrotron radiation investigation of cathode materials for aqueous Zn-ion batteries.

In view of the advantages of low cost, environmental sustainability, and high safety, aqueous Zn-ion batteries (AZIBs) are widely expected to hold significant promise and increasingly infiltrate various applications in the near future. The development of AZIBs closely relates to the properties of cathode materials, which depend on their structures and corresponding dynamic evolution processes. Synchrotron radiation light sources, with their rich advanced experimental methods, serve as a comprehensive characterization platform capable of elucidating the intricate microstructure of cathode materials for AZIBs. In this review, we initially examine available cathode materials and discuss effective strategies for structural regulation to boost the storage capability of Zn2+. We then explore the synchrotron radiation techniques for investigating the microstructure of the designed materials, particularly through in situ synchrotron radiation techniques that can track the dynamic evolution process of the structures. Finally, the summary and future prospects for the further development of cathode materials of AZIBs and advanced synchrotron radiation techniques are discussed.

Carbon ion irradiation exerts antitumor activity by inducing cGAS-STING activation and immune response in prostate cancer-bearing mice.

As an advanced radiotherapy technique, carbon ion radiotherapy has demonstrated good efficacy and low toxicity for prostate cancer patients, but the radiobiological mechanism of killing tumor cells has not been fully elucidated. This study aims to explore the antitumor effects of carbon ion irradiation (CIR) through investigating the immune response induced by CIR in prostate cancer-bearing mice and the underlying molecular mechanism. We established subcutaneous transplantation tumor models of prostate cancer to evaluate the tumor inhibition effect of CIR. Investigation of immunophenotype alterations were assessed by flow cytometry. Immunofluorescence, western blot, and real-time quantitative PCR was employed to analyze the activation of cGAS-STING pathway. CIR showed more powerful tumor growth control than photon irradiation in immunocompetent syngeneic C57BL/6 mice. CIR exerts antitumor effect by triggering immune response, characterized by increased CD4+ T cells and macrophages in tumor, enhanced CD8+ T cells and T effector memory cells in spleen, improved IFN-γ production of CD8+ tumor-infiltrating lymphocytes, and reduced exhausted T cells in tumor and spleen. Additionally, production of cytoplasmic double-stranded DNA, protein levels of p-TBK1 and p-IRF3 in the cGAS-STING pathway, and gene expression levels of downstream interferon-stimulated genes were significantly increased after CIR in a dose-dependent manner. Treatment of RM1 tumor-bearing mice with the STING inhibitor C-176 impaired the antitumor effect of CIR. The excellent antitumor activity of CIR in immunocompetent prostate cancer-bearing C57BL/6 mice may be attributed to stronger induction of antitumor immune response and higher activation of cGAS-STING pathway.

Celiac plexus radiosurgery - an introduction to the method and a practical manual.

Celiac plexus radioablation (CPR) is an emerging non-invasive interventional treatment for severe pain associated with cancer-related damage to the celiac plexus. Due to its complex aetiology, such pain often responds poorly to conventional analgesics, and high doses of these medications can cause toxicity. Celiac plexus radiosurgery employs advanced radiotherapy techniques to administer a high single dose of 25 Gy to the anatomically defined celiac plexus, aiming to reduce pain intensity and enhance patients' quality of life. The safety and efficacy of CPR have been validated in a prospective single-arm clinical trial that included 125 patients. The positive outcomes of this trial led to the integration of CPR into pain management guidelines; however, the novel approach to radiotherapy planning might be initially challenging to grasp. In this article, we provide a brief overview of the method along with a comprehensive, Polish and English-language guide on how to perform CPR and manage patients, based on our clinical experience.

Whole-brain radiotherapy with hippocampus sparing and simultaneous integrated boost to metastases: A plan quality comparison study between Ethos, HyperArc, VMAT and Tomotherapy

This study provides a concise and structured overview of a dosimetric comparison study conducted to assess the feasibility and effectiveness of 4 advanced radiotherapy techniques in treating brain metastases with hippocampus sparing and simultaneous integrated boost (HS-WBRT+SIB). Eleven patients with brain metastases previously treated with radiotherapy were included in the study. Planning CT scans with 2 mm slice thickness and MR imaging were used for contouring and dose prescription. The bilateral hippocampus and other organs at risk (OARs) were automatically contoured, and hippocampal avoidance regions (HAR) were defined as a 7 mm 3D expansion around the hippocampus. Gross tumor volume for each metastasis (GTVmet) and planning target volume for metastases (PTVmet) were delineated. The whole-brain CTV (CTVWB) and planning target volume for whole brain (PTVWB) were defined accordingly. Treatment planning and optimization were conducted using state-of-the-art radiotherapy techniques: Ethos, HyperArc, VMAT, and Tomotherapy. Tomotherapy achieved the highest D98% for PTVmet, indicating the best metastasis coverage. HyperArc plans showed the highest D98% for PTVWB, suggesting superior whole-brain coverage. Tomotherapy demonstrated significantly lower D98%, D2%, and Dmean values for the hippocampus, indicating its superiority in sparing the hippocampus. VMAT resulted in the lowest D2% values for the eyes, optic nerves, brainstem, and hypophysis, showing the best sparing of these critical structures. Tomotherapy consistently achieved lower Dmean values for parotids, oral cavity, and lips compared to the other techniques. The dosimetric comparison revealed distinct strengths and weaknesses for each radiotherapy technique. Tomotherapy excelled in sparing the hippocampus, while VMAT showed promise in sparing OARs. HyperArc plans demonstrated the best overall whole-brain coverage. These findings should guide clinicians in selecting the most suitable technique based on patient characteristics and institutional resources.

Making incurable pancreatic cancer curable

AbstractPancreatic cancer is one of the deadliest malignancies, with limited effectiveness of standard therapies, resulting in little improvement in the 5‐year survival rate over the past few decades. However, advanced radiotherapy techniques and emerging treatment modalities, such as immunotherapy and targeted therapy, are showing tremendous potential as effective treatment options for pancreatic cancer patients who were previously considered incurable. This review summarizes the current advances and challenges in pancreatic cancer treatment strategies and proposes further optimization directions, aiming to provide insights into the cure of incurable pancreatic cancer.

Systemic Therapy for Melanoma Brain and Leptomeningeal Metastases.

Melanoma has a high propensity to metastasize to the brain which portends a poorer prognosis. With advanced radiation techniques and targeted therapies, outcomes however are improving. Melanoma brain metastases are best managed in a multi-disciplinary approach, including medical oncologists, neuro-oncologists, radiation oncologists, and neurosurgeons. The sequence of therapies is dependent on the number and size of brain metastases, status of systemic disease control, prior therapies, performance status, and neurological symptoms. The goal of treatment is to minimize neurologic morbidity and prolong both progression free and overall survival while maximizing quality of life. Surgery should be considered for solitary metastases, or large and/or symptomatic metastases with edema. Stereotactic radiosurgery offers a benefit over whole-brain radiation attributed to the relative radioresistance of melanoma and reduction in neurotoxicity. Thus far, data supports a more durable response with systemic therapy using combination immunotherapy of ipilimumab and nivolumab, though targeting the presence of BRAF mutations can also be utilized. BRAF inhibitor therapy is often used after immunotherapy failure, unless a more rapid initial response is needed and then can be done prior to initiating immunotherapy. Further trials are needed, particularly for leptomeningeal metastases which currently require the multi-disciplinary approach to determine best treatment plan.

Acute and Chronic Complications After Treatment of Locoregional Anal Cancer: Prevention and Management Strategies.

Definitive chemoradiotherapy (CRT) for anal cancer spares patients the morbidity of a colostomy surgery and optimizes cancer outcomes. CRT, however, has introduced a unique acute and chronic toxicity profile, which has greatly improved over the years with the introduction of advanced radiotherapy techniques. This article provides the multidisciplinary care team with practical tools to mitigate and manage acute and chronic complications from definitive treatment of anal cancer.