Radiotherapy For Cancer Research Articles

Enhancing Visualization of Gold Markers in Prostate Cancer Radiation Therapy Planning Through MRI Pulse Sequence Optimization

Prostate cancer treatment often involves the use of gold markers to enhance the accuracy of radiation therapy. However, the visualization of these markers using MRI remains a challenge due to their small size and susceptibility to artifacts. This study investigates the optimization of MRI pulse sequences to improve the visibility of gold markers in the context of radiation therapy simulation for prostate cancer patients. By comparing various pulse sequences and their parameters, we aim to identify the optimal configuration that provides the best contrast and minimal artifacts.

Radiochemical separation of 161 Tb from neutron irradiated Gd target by liquid-liquid extraction technique

Abstract No-carrier-added (NCA) 161 Tb, which has advisable nuclear properties to be applied for cancer radiotherapy was produced at the Egyptian Second Research Reactor (ETRR-2) by neutron irradiation of natural gadolinium target via indirect nuclear reaction. The radiochemical separation of 161 Tb from irradiated gadolinium target was investigated based on solvent extraction technique using Cyanex 302. Several separation parameters were checked and optimized. According to the obtained results, the separation process of the investigated radioisotopes proceeds in two steps. The first step is an extraction of all of them into the organic phase in which the extraction % (98 %) was optimized at pH 4, 0.15 M of Cyanex 302 and 2.5 h extraction time. Moreover, the slope analysis method confirmed the participation of 2 mol of the organic extractant for the separation of 161 Tb from irradiated gadolinium. The second step is the separation of the 161 Tb isotope that was purified by the stripping of 159Gd with a citrate solution at pH 9, which is considered as a highly efficient and promising method for separation and purification of the two radioisotopes.

Visualization of Biomolecular Radiation Damage at the Single-Particle Level Using Lanthanide-Sensitized DNA Origami.

Precise monitoring of biomolecular radiation damage is crucial for understanding X-ray-induced cell injury and improving the accuracy of clinical radiotherapy. We present the design and performance of lanthanide-DNA-origami nanodosimeters for directly visualizing radiation damage at the single-particle level. Lanthanide ions (Tb3+ or Eu3+) coordinated with DNA origami nanosensors enhance the sensitivity of X-ray irradiation. Atomic force microscopy (AFM) revealed morphological changes in Eu3+-sensitized DNA origami upon X-ray irradiation, indicating damage caused by ionization-generated electrons and free radicals. We further demonstrated the practical applicability of Eu3+-DNA-origami integrated chips in precisely monitoring radiation-mediated cancer radiotherapy. Quantitative results showed consistent trends with flow cytometry and histological examination under comparable X-ray irradiation doses, providing an affordable and user-friendly visualization tool for preclinical applications. These findings provide new insights into the impact of heavy metals on radiation-induced biomolecular damage and pave the way for future research in developing nanoscale radiation sensors for precise clinical radiography.

Multi-scale anatomical regularization for domain-adaptive segmentation of pelvic CBCT images.

Cone beam computed tomography (CBCT) image segmentation is crucial in prostate cancer radiotherapy, enabling precise delineation of the prostate gland for accurate treatment planning and delivery. However, the poor quality of CBCT images poses challenges in clinical practice, making annotation difficult due to factors such as image noise, low contrast, and organdeformation. The objective of this study is to create a segmentation model for the label-free target domain (CBCT), leveraging valuable insights derived from the label-rich source domain (CT). This goal is achieved by addressing the domain gap across diverse domains through the implementation of a cross-modality medical image segmentationframework. Our approach introduces a multi-scale domain adaptive segmentation method, performing domain adaptation simultaneously at both the image and feature levels. The primary innovation lies in a novel multi-scale anatomical regularization approach, which (i) aligns the target domain feature space with the source domain feature space at multiple spatial scales simultaneously, and (ii) exchanges information across different scales to fuse knowledge from multi-scaleperspectives. Quantitative and qualitative experiments were conducted on pelvic CBCT segmentation tasks. The training dataset comprises 40 unpaired CBCT-CT images with only CT images annotated. The validation and testing datasets consist of 5 and 10 CT images, respectively, all with annotations. The experimental results demonstrate the superior performance of our method compared to other state-of-the-art cross-modality medical image segmentation methods. The Dice similarity coefficients (DSC) for CBCT image segmentation results is %, and the average symmetric surface distance (ASSD) is . Statistical analysis confirms the statistical significance of the improvements achieved by ourmethod. Our method exhibits superiority in pelvic CBCT image segmentation compared to its counterparts.

Adjuvant (chemo)radiotherapy for patients with head and neck cancer: can comorbidity risk scores predict outcome?

This study compares the objective American Society of Anesthesiologists (ASA) and Adult Comorbidity Evaluation-27 (ACE-27) scores with the subjective Eastern Cooperative Oncology Group performance status (ECOG PS) for patient outcome prediction. We retrospectively analyzed head and neck squamous cell carcinoma patients treated with adjuvant (chemo)radiotherapy at the LMU Munich from June 2008 to June 2015. The study focused on associations between patient outcomes; treatment failures; known risk factors (including human papillomavirus [HPV] status and tumor stage); and the comorbidity indices ECOG-PS, ASA score, and ACE-27. The Kaplan-Meier method and Cox proportional hazards model were used for survival analysis and identifying independent risk factors. A total of 302 patients were analyzed, 175 received concurrent chemotherapy. Median follow-up was 61.8 months, and median age at diagnosis was 61years. The 3‑ and 5‑year overall survival (OS) and disease-free survival (DFS) rates were 70.5%/60.2% and 64.7%/57.6%, respectively. Both ACE-27 and ASA showed significant correlations with OS in univariate and multivariate analyses, while ECOG-PS was significant only in univariate analysis. ASA and ACE-27 scores were also significantly correlated with local and locoregional recurrence, but only HPV status and tumor stage were significant in multivariate models. ACE-27 and ASA score effectively categorize patients' risks in adjuvant radiotherapy for head and neck cancer, proving more predictive of overall survival than ECOG-PS. These results underscore the importance of objective comorbidity assessment and suggest further prospective studies.

The scientific nature of the linear no-threshold (LNT) model used in the system of radiological protection.

During the first half of the 20th century, it was commonly assumed that radiation-induced health effects occur only when the dose exceeds a certain threshold. This idea was discarded for stochastic effects when more knowledge was gained about the mechanisms of radiation-induced cancer. Currently, a key tenet of the international system of radiological protection is the linear no-threshold (LNT) model where the risk of radiation-induced cancer is believed to be directly proportional to the dose received, even at dose levels where the effects cannot be proven directly. The validity of the LNT approach has been questioned on the basis of a claim that only conclusions that can be verified experimentally or epidemiologically are scientific and LNT should, thus, be discarded because the system of radiological protection must be based on solid science. The aim of this publication is to demonstrate that the LNT concept can be tested in principle and fulfils the criteria of a scientific hypothesis. The fact that the system of radiological protection is also based on ethics does not render it unscientific either. One of the fundamental ethical concepts underlying the LNT model is the precautionary principle. We explain why it is the best approach, based on science and ethics (as well as practical experience), in situations of prevailing uncertainty.

Coping with modesty during radiotherapy for breast cancer: a multicentric study.

Breast cancer is the most frequently diagnosed tumour, representing nearly 30% of all new cases in women. Radiotherapy (RT) plays a crucial role in the management of breast cancer. The objective of this study is to assess modesty in patients undergoing RT for breast cancer and take their suggestions and ideas into consideration to enhance the quality of treatment in this regard. The study enrolled 555 breast cancer patients undergoing adjuvant RT in three Italian centres. Patients completed a self-test questionnaire assessing their comfort level concerning modesty during therapy and their relationship with strangers and healthcare professionals. The impact of religious views and potential changes in sexuality were also examined. Results showed that modesty was a common concern across the overall cohort of patients, with discomfort in being undressed during RT correlating with discomfort experienced in other daily life situations. Most patients felt more at ease with same sex healthcare workers. Age was also a major factor with younger patients generally feeling more comfortable with healthcare workers of the same age group. Interestingly, the surgical technique used (mastectomy vs. quadrantectomy) did not significantly influence modesty perceptions. Patients provided valuable suggestions to improve privacy and modesty during RT. This study demonstrates that modesty is an important issue for women undergoing RT, which can be influenced by personal characteristics and hospital-related factors. A reflection about the need to address modesty concerns and to incorporate dedicated interventions for protecting patients' physical and emotional well-being is warranted. Initiatives to improve communication, involvement, and body image support should also be integrated into the care path of patients to better their overall therapeutic experience. This study paves the way for broader research and interventions in daily cancer care.

Modern radiation therapy for keratinocyte cancer: What the general practitioner needs to know.

Keratinocyte cancer (KC) in Australia poses a unique healthcare challenge due to its high prevalence and the requirement for multidisciplinary management of many cases. Advances in radiation therapy (RT) have increased its use in treating different keratinocyte cancer presentations. Understanding the indications for RT and the role that general practitioners (GPs) play in the treatment pathway are imperative to ensure best patient outcomes. This review examined the efficacy, advances and treatment considerations of RT for the management of keratinocyte cancer, and role of the GP in the treatment pathway. Radiation therapy offers effective alternatives to, or adjuvants for, surgery in existing keratinocyte cancer treatments in appropriate cases. The evolving RT landscape necessitates GPs to be well informed for effective case identification, referral and management. This includes understanding RT advances, protocols, treatment reactions and managing patient expectations. Continuing education in this space is important for GPs to understand the suitability of RT for their patients.

Transition of Online Adaptive Stereotactic Radiotherapy for Pancreatic Cancer From Magnetic Resonance-Guided Linear Accelerator (MR-Linac) to State-of-the-Art Cone-Beam Computed Tomography (CBCT)

Transition of Online Adaptive Stereotactic Radiotherapy for Pancreatic Cancer From Magnetic Resonance-Guided Linear Accelerator (MR-Linac) to State-of-the-Art Cone-Beam Computed Tomography (CBCT)

Efficacy and Safety of Nimotuzumab in Combination with Radiotherapy or Chemoradiotherapy for Local Advanced Head and Neck Cancer: A Systematic Review and Meta-analysis.

The present meta-analysis aimed to evaluate the efficacy and safety of adding nimotuzumab to radiotherapy (RT) or chemoradiotherapy (CRT). Prospective randomized controlled studies at EMBASE, PubMed, and the Cochrane Library from January 1, 2010, to October 1, 2022, were searched. Data on the overall survival (OS), progress-free survival (PFS), disease-free survival (DFS), complete response rate (CRR), objective response rate (ORR), and all grade adverse events were collected from the enrolled publications. OS was the primary measurement indicator. Pooled analysis was performed with relative risks (RRs), hazard risks (HRs), and their corresponding 95% confidence intervals (CIs) in the software Stata SE 16.0. Six randomized controlled studies were included in the analysis of the overall pooled effect. As compared to the control group, the nimotuzumab intervention group exhibited improved OS by 21% (pooled HR=0.79,95% CI: 0.64-0.98, P=0.028), along with PFS up to 31% (HR=0.69, 95% CI: 0.55-0.86, P=0.001) and DFS up to 29% (HR=0.71, 95% CI: 0.56-0.91, P=0.006), increased CRR as 50% (RR=1.50, 95% CI:1.09-2.04; P=0.012), and ORR as 35% (RR=1.35, 95% CI:1.04-1.73; P=0.022). Regarding safety, nimotuzumab in combination with RT or CRT did not increase the incidence of all grade adverse events (pooled-RD=-1.27, 95% CI:-2.78-0.23, P=0.099). The present meta-analysis has demonstrated that nimotuzumab, in combination with RT or CRT, could provide survival benefits and increase response rates. Its safety profile has been found to be controllable.

Artificial intelligence-generated targets and inter-observer variation in online adaptive radiotherapy of bladder cancer

Background and purposeDaily target re-delineation in online adaptive radiotherapy (oART) introduces uncertainty. The aim of this study was to evaluate artificial intelligence (AI) generated contours and inter-observer target variation among radiotherapy technicians in cone-beam CT (CBCT) guided oART of bladder cancer. Materials and methodsFor each of 10 consecutive patients treated with oART for bladder cancer, one CBCT was randomly selected and retrospectively included. The bladder (CTV-T) was AI-segmented (CTV-TAI). Seven radiotherapy technicians independently reviewed and edited CTV-TAI, generating CTV-TADP. Contours were benchmarked against a ground truth contour (CTV-TGT) delineated blindly from scratch. CTV-TADP and CTV-TAI were compared to CTV-TGT using volume, dice similarity coefficient, and bidirectional local distance. Dose coverage (D99%>95 %) of CTV-TGT was evaluated for treatment plans optimized for CTV-TAI and CTV-TADP with clinical margins. Inter-observer variation among CTV-TADP was assessed using coefficient of variation and generalized conformity index. ResultsCTV-TGT ranged from 48.7 cm3 to 211.6 cm3. The median [range] volume difference was 4.5 [−17.8, 42.4] cm3 for CTV-TADP and −15.5 [−54.2, 4.3] cm3 for CTV-TAI, compared to CTV-TGT. Corresponding dice similarity coefficients were 0.87 [0.71, 0.95] and 0.84 [0.64, 0.95]. CTV-TGT was adequately covered in 68/70 plans optimized on CTV-TADP and in 6/10 plans optimized on CTV-TAI with clinical margins. The median [range] coefficient of variation was 0.08 [0.05, 0.11] and generalized conformity index was 0.78 [0.71, 0.88] among CTV-TADP. ConclusionsTarget re-delineation in CBCT-guided oART of bladder cancer demonstrated non-isotropic inter-observer variation. Manual adjustment of AI-generated contours was necessary to cover ground truth targets.

Radiation-Induced Childhood Thyroid Cancer after the Fukushima Daiichi Nuclear Power Plant Accident

After the Fukushima Nuclear Power Plant accident in March 2011, a large-scale ultrasound examination of childhood thyroid cancer for all Fukushima residents aged 18 years old or younger was initiated. Fukushima was divided into four areas according to the external radioactivity released by the accident: the highest (A), high-intermediate (B), low-intermediate (C), and the lowest (D). Five rounds of surveys were carried out from October 2011 to March 2023. The annual incidence rates of the “Common Case” not affected by the accident were able to be estimated. The difference between the incidence rate of whole patients and the “Common Case” is that of the “Radiation-induced Case”. The annual incidence rate of the “Radiation-induced Case” began to increase immediately after the accident, where the highest level was seen in A area, and the order was A > B > C > D. It showed that the development of childhood thyroid cancer was affected by the radiation released by the accident. The effect of the radiation consisted of two phases: the first phase may have been due to the damage to the immune system, and the second phase may have been due to the genetic mutation in the children who were youngest at the time of the accident.

Application of machine learning algorithm to create a prediction model for the need of aggressive nutritional intervention during head and neck cancer radiotherapy

Application of machine learning algorithm to create a prediction model for the need of aggressive nutritional intervention during head and neck cancer radiotherapy

Evaluating the Effectiveness of Proton Beam Therapy Compared to Conventional Radiotherapy in Non-Metastatic Rectal Cancer: A Systematic Review of Clinical Outcomes

Background and Objectives: Conventional radiotherapies used in the current management of rectal cancer commonly cause iatrogenic radiotoxicity. Proton beam therapy has emerged as an alternative to conventional radiotherapy with the aim of improving tumour control and reducing off-set radiation exposure to surrounding tissue. However, the real-world treatment and oncological outcomes associated with the use of proton beam therapy in rectal cancer remain poorly characterised. This systematic review seeks to evaluate the radiation dosages and safety of proton beam therapy compared to conventional radiotherapy in patients with non-metastatic rectal cancer. Materials and Methods: A computer-assisted search was performed on the Medline, Embase and Cochrane Central databases. Studies that evaluated the adverse effects and oncological outcomes of proton beam therapy and conventional radiotherapy in adult patients with non-metastatic rectal cancer were included. Results: Eight studies were included in this review. There was insufficient evidence to determine the adverse treatment outcomes of proton beam therapy versus conventional radiotherapy. No current studies assessed radiotoxicities nor oncological outcomes. Pooled dosimetric comparisons between proton beam therapy and various conventional radiotherapies were associated with reduced radiation exposure to the pelvis, bowel and bladder. Conclusions: This systematic review demonstrates a significant paucity of evidence in the current literature surrounding adverse effects and oncological outcomes related to proton beam therapy compared to conventional radiotherapy for non-metastatic rectal cancer. Pooled analyses of dosimetric studies highlight greater predicted radiation-sparing effects with proton beam therapy in this setting. This evidence, however, is based on evidence at a moderate risk of bias and clinical heterogeneity. Overall, more robust, prospective clinical trials are required.

3216: Can we predict response after stereotactic body radiotherapy in oligometastatic breast cancer?

3216: Can we predict response after stereotactic body radiotherapy in oligometastatic breast cancer?

Exposure to endocrine disruptor DEHP promotes the progression and radiotherapy resistance of pancreatic cancer cells by increasing BMI1 expression and properties of cancer stem cells

Most patients diagnosed with pancreatic cancer are initially at an advanced stage, and radiotherapy resistance impact the effectiveness of treatment. This study aims to investigate the effects of endocrine disruptor Di-(2-ethylhexyl) phthalate (DEHP) on various biological behaviors and the radiotherapy sensitivity of pancreatic cancer cells, as well as its potential mechanisms. Our findings indicate that exposure to DEHP promotes the proliferation of various cancer cells, including those from the lung, breast, pancreas, and liver, in a time- and concentration-dependent manner. Furthermore, DEHP exposure could influence several biological behaviors of pancreatic cancer cells in vivo and vitro. These effects include reducing cell apoptosis, causing G0/G1 phase arrest, increasing migration capacity, enhancing tumorigenicity, elevating the proportion of cancer stem cells (CSCs), and upregulating expression levels of CSCs markers such as CD133 and BMI1. DEHP exposure can also increase radiation resistance, which can be reversed by downregulating BMI1 expression. In summary our research suggests that DEHP exposure can lead to pancreatic cancer progression and radiotherapy resistance, and the mechanism may be related to the upregulation of BMI1 expression, which leads to the increase of CSCs properties.

910: Comparison of Eclipse and RayStation in Multi-Criteria Optimization in Prostate Cancer Radiotherapy

910: Comparison of Eclipse and RayStation in Multi-Criteria Optimization in Prostate Cancer Radiotherapy

Permanent Indian ink tattoos for breast cancer radiotherapy: A United Kingdom study of the emotional impact on patients following radiotherapy

BackgroundPost-operative radiotherapy for early breast cancer is recommended for over 30,000 people every year in the United Kingdom. The majority of these patients will be advised to have radiotherapy alignment tattoos; permanent skin marks applied with Indian ink and a lancing needle, black/green/blue in colour and approximately 2 mm in diameter. The tattoos assist the therapeutic radiographers to position the patient accurately and reproducibly for each treatment fraction. The aim of this study was to investigate the emotional impact of radiotherapy tattoos on people following breast cancer radiotherapy. MethodsAn electronic questionnaire was distributed by the charitable organisation, Breast Cancer Now, to their members who had undergone radiotherapy for early breast cancer. Based on the responses to the open and closed questions, an overall impact score was assigned to each respondent, and representative quotes extracted to contextualise the themes identified. Statistical tests were performed to evaluate the relationship between overall impact scores and several variables such as age at the time of radiotherapy, skin type, and age at the time of completing the questionnaire. Results204 people responded to the questionnaire. 100% had permanent Indian ink tattoos during breast cancer radiotherapy. 95% could still see the midline tattoo. 22 subthemes; 4 positive, 4 neutral and 14 negative. Radiotherapy tattoos served as a constant negative reminder for 27% and affected clothing choices in 14% of respondents. 11% described feelings of ‘hating’ them. 6% were assigned positive overall impact scores, 43% neutral, and 51% had negative overall impact scores. The black/green/blue ink pigment used was commonly described as unnatural; contributing strongly to the negative appearance of the tattoos. ConclusionPermanent Indian ink tattoos have a negative impact on emotional well-being in the months and years following radiotherapy for early breast cancer for many people. In contrast, a very small minority feel positively about the tattoos. Implications for practiceOur findings are unlikely to be unique to this diagnostic cohort and supports the need to offer alternatives that are less-impactful to the recipient, accessible for people of all skin colours, and fit-for-purpose in terms of radiotherapy set-up. Acknowledgement of the significant negative impact and collaboration between industry, healthcare professionals and patient representatives is key to identifying and implementing suitable alternatives as standard of care.

Intraoperative radiation therapy for early-stage breast cancer.

Intraoperative radiotherapy (IORT) offers more convenience compared to external beam radiotherapy (EBRT) following breast-conserving surgery for early-stage breast cancer. This study describes the implementation of IORT at a metropolitan academic cancer center. Demographics, tumor characteristics, margin status, adjunct EBRT, and cosmetic results were retrospectively analyzed in patients undergoing BCS with IORT. IORT consists of 20 gray delivered to the partial mastectomy cavity. From 2015 to 2020, 171 patients (65.5% African American) were included. Histologically, 104 (60.8%) patients had invasive ductal carcinoma (IDC), while 67 (39%) patients had DCIS only. Seventeen (15.9%) patients with IDC and 12 (8.6%) patients with DCIS had positive margins. There were 15 ipsilateral breast recurrences (8.8%) and three patients (20%) developed systemic disease. Twenty-five patients (14.6%) underwent adjuvant EBRT. The local recurrence-free survival at 60 months from date of IORT was 89.4% (95% CI 82.7%-93.6%). For overall survival (OS), 168 (98.2%) patients were alive at a median follow-up of 51.4 months, and three total deaths were recorded. IORT is a highly desirable and convenient alternative to EBRT for early-stage breast cancer especially for patients with poor compliance. IORT has an acceptable ipsilateral recurrence while not precluding adjunct EBRT based upon the final pathologic report.

Postoperative Radiotherapy Using VMAT for RNI Including IMN in Breast Cancer: Report of Short-term Follow-up.

The application of volumetric-modulated arc therapy (VMAT) in postoperative radiotherapy for breast cancer has recently garnered considerable interest, especially when regional lymph node irradiation (RNI), is extended to include the internal mammary node (IMN) region, along with whole-breast or chest wall irradiation. This study aimed to assess both acute and late toxicities, as well as breast cancer outcomes, during the observation period. This retrospective study aimed to assess the safety and feasibility of VMAT in postoperative radiotherapy, including the IMN region, for patients with breast cancer at our hospital. We included 33 eligible patients who received postoperative VMAT radiotherapy, including the IMN region, between November 2018 and July 2021. The primary indications for implementing VMAT were the presence of IMN metastases before primary systemic therapy or more than four axillary lymph node metastases. The median prescribed dose for the chest wall or conserved breast and regional lymph nodes was 50 Gy in 25 fractions. In 16 cases, a simultaneous boost (median, 10 Gy) was administered to residual lymph node metastases. VMAT facilitated a reduction in the mid- or high-dose range to organs at risk, exemplified by V20Gy and V40Gy of the ipsilateral lung, which were 24.10% and 6.84%, respectively, while ensuring adequate target dose irradiation, V45Gy=95.23%. No serious adverse events, including symptomatic radiation pneumonitis, occurred during the 15-month median observation period. Our findings demonstrate the safety and effectiveness of postoperative radiotherapy for breast cancer, including the IMN region, when using VMAT.