Radiotherapy For Breast Cancer Research Articles

Development of automated region of interest selection algorithms for surface-guided radiation therapy of breast cancer.

To investigate automation of the preparation of the region of interest (ROI) for surface-guided radiotherapy (SGRT) of the whole breast with two algorithms based on contour anatomies: using the body contour, and using the breast contour. The patient dataset used for modeling consisted of 39 breast cancer patients previously treated with SGRT. The patient's anatomical structures (body and ipsilateral breast) were retrieved from the planning system, and the clinical ROI (cROI) drawn by the planners was retrieved from the SGRT system for comparison. For the body-contour-based algorithm, a convolutional neural network (MobileNet-v2) was utilized to train a synthetic human model dataset to predict body joint locations. With the body joint location knowledge, an automated ROI (aROIbody ) can be created based on: (1) the superior-inferior (S-I) borders defined by the joint locations, (2) the left-right (L-R) borders defined with 3/4 of chest width, and (3) a curation of the ROI to avoid the ipsilateral armpit. For the breast-contour-based algorithm, an aROIbreast was created by first defining the ROI in the S-I direction with the ipsilateral breast boundaries. Other steps are the same as with the body-contour-based algorithm. Among the 39 patients, 24 patients were used to fine-tune the algorithm parameters, and the remaining 15 patients were used to evaluate the quality of the aROIs against the cROIs. A blinded evaluation was performed by three SGRT expert physicists to rate the acceptability and the quality (1-10 scale) of the aROIs and cROIs, and the dice similarity coefficient (DSC) was also calculated to compare the similarity between the aROIs and cROIs. The results showed that the average acceptability was 14/15 (range: 13/15-15/15) for cROIs, 13.3/15 (range: 13/15-14/15) for aROIbody , and 14.6/15 (range: 14/15-15/15) for aROIbreast . The average quality was 7.4 ± 0.8 for cROIs, 8.1 ± 1.2 for aROIbody , and 8.2 ± 0.9 for aROIbreast . The DSC with cROIs was 0.81 ± 0.06 for aROIbody , and 0.83 ± 0.04 for aROIbreast . The ROI creation time was ∼120s for clinical, 1.3s for aROIbody , and 1.2s for aROIbreast . The proposed automated algorithms can improve the ROI compliance with the SGRT protocol, with a shortened preparation time. It is ready to be integrated into the clinical workflow for automated ROI preparation.

Protocol of the HISTOTHERM study: assessing the response to hyperthermia and hypofractionated radiotherapy in recurrent breast cancer.

Breast cancer is globally the leading cancer in women, and despite the high 5-year survival rate the most frequent cause of cancer related deaths. Surgery, systemic therapy and radiotherapy are the three pillars of curative breast cancer treatment. However, locoregional recurrences frequently occur after initial treatment and are often challenging to treat, amongst others due to high doses of previous radiotherapy treatments. Radiotherapy can be combined with local hyperthermia to sensitize tumor cells to radiation and thereby significantly reduce the required radiation dose. Therefore, the combination treatment of mild local hyperthermia, i.e. locally heating of the tissue to 39-43°C, and re-irradiation with a reduced total dose is a relevant treatment option for previously irradiated patients. The mechanisms of this effect in the course of the therapy are to date not well understood and will be investigated in the HISTOTHERM study. Patients with local or (loco)regional recurrent breast cancer with macroscopic tumors are included in the study. Local tumor control is evaluated clinically and histologically during the course of a combination treatment of 60 minutes mild superficial hyperthermia (39 - 43°C) using water-filtered infrared A (wIRA) irradiation, immediately followed by hypofractionated re-irradiation with a total dose of 20-24 Gy, administered in weekly doses of 4 Gy. Tumor and tumor stroma biopsies as well as blood samples will be collected prior to treatment, during therapy (at a dose of 12 Gy) and in the follow-up to monitor therapy response. The treatment represents the standard operating procedure for hyperthermia plus re-irradiation. Various tissue and blood-based markers are analyzed. We aim at pinpointing key mechanisms and markers for therapy response which may help guiding treatment decisions in future. In addition, quality of life in the course of treatment will be assessed and survival data will be evaluated. The study is registered at the German Clinical Trials Register, Deutsches Register Klinischer Studien (DRKS00029221).

Failure mode and effects analysis in consensus-based GDM for surface-guided deep inspiration breath-hold breast radiotherapy for breast cancer under the framework of linguistic Z-number

Most of the cancer patients cannot get the usual treatment in the advanced stage of the disease. In particular, for breast cancer, it is to use a special kind of radiation that targets the tumor while the patient holds their breath. This is called surface-guided (SG) breast radiotherapy (RT) with deep inspiration breath-hold (DIBH). This treatment is very complicated and different from the normal way of treating breast cancer. It can also have many errors and problems that are not well-studied or understood. To prevent these problems, we need to use a method called failure mode and effects analysis (FMEA). This method helps us find and rank the possible risks and how to avoid them. In keeping with this aim, this paper studies consensus-reaching process-based group decision-making (GDM) with completely unknown risk factors' weights and the gained-lost dominance score (GLDS)-based ranking process. We cannot avoid the uncertainty related to relativity information in medical science. Therefore, in this study, we offer the experts to provide their opinions using the linguistic Z number (LZN) because LZN is designed to capture such types of information in medical science. For the consensus-reaching process (CRP), the relativity among experts is considered for consensus measurement, and the minimum adjustment sum with group consensus opinion-based feedback is offered. For unknown weight of risk factors, we don't know how much each risk factor weighs. So, we use a method that combines two ways of calculating weights. One way is a subjective weight computation process, and the other way is based on the data using entropy and division. Finally, we applied our proposed CRP-based GDM approach for ranking the identified FMs related to the SG DIBH RT process. We conduct sensitive, comparative, and statistical assessments to ensure our method is reasonable and practical.

Duplex Imaging Assessment of the Internal Mammary Arteries in Women after Unilateral Mastectomy and Radiotherapy for Breast Cancer

The effects of incidental radiation exposure on internal mammary arteries remain unclear. The present study was designed to test the hypothesis by comparing diameter and blood flow of the irradiated and nonirradiated internal mammary arteries, using Duplex ultrasound imaging. The study was designed as a single-center, transversal, comparative study. The main outcomes were diameter and volumetric blood flow of the internal mammary arteries. The Wilcoxon rank-sum test was used to assess the differences between the irradiated and nonirradiated internal mammary arteries with regard to the diameter and volumetric blood flow. The diameter (median [interquartile range]) of the irradiated internal mammary arteries (0.170mm [0.160, 0.180]) was smaller than that of the contralateral nonirradiated ones (0.180mm [0.170, 0.200], P<0.0001) and that of the internal mammary arteries in the control group (0.180mm [0.170, 0.190], P<0.0001). Similarly, blood flow (median [interquartile range]) of the irradiated internal mammary arteries (52.4ml/min [37.78, 65.57]) was smaller than that of the contralateral nonirradiated ones (62.7ml/min [46.87, 84.17], P<0.0001), as well as of the left (56.7ml/min [46.88, 72.58], P=0.02) and the right internal mammary arteries in the control group (61.0ml/min [47.47, 74.52], P=0 0.0009). The data indicate that the irradiated internal mammary arteries in patients with a history of total mastectomy followed by radiotherapy for breast cancer had significantly smaller diameter and blood flow compared to the nonirradiated internal mammary arteries.

Women's Preferences for Hypofractionated Radiation Therapy for Treatment of Early-Stage Breast Cancer: A Discrete Choice Experiment

IntroductionThe primary treatment recommended for early-stage breast cancer is breast conserving surgery followed by external beam radiation therapy of the whole breast. Previously radiation therapy for early-stage breast cancer was given using more fractions over longer durations. Guidelines support treatments with fewer fractions over a shorter time (hypofractionated radiation therapy-HFRT). This study aimed to understand women's preferences for different features of treatments for early-stage breast cancer. MethodsA discrete choice experiment (DCE) with 12 choice tasks was conducted, describing the treatments by: extent of surgery, duration of radiation treatment, need to relocate for treatment, local side effects, changes in breast appearance, costs, and difficulty with daily activities during and after treatment. Participants were women with breast cancer and from the general population. Mixed logit analyses were conducted and trade-offs between attributes estimated. Results420 respondents completed the DCE. The relative importance of attributes varied by respondent characteristics; the most influential attribute for younger women was type of surgery (breast conserving surgery); type of surgery did not influence older women's preferences. Shorter treatment duration, avoiding relocation, fewer local side effects, and less difficulty with daily activities all positively influenced treatment preference. Younger women were willing to accept 32-40 days of radiation treatment before a treatment that included mastectomy was potentially acceptable. Conclusionattributes of treatment such as duration, need for relocation, side effects and impacts on normal daily activities during and after treatment significantly influenced women's preference for treatment, including surgery. Our findings have the potential for real impact for patients and services including supporting one on one clinical discussions, supporting program and patient resource development, and by informing service funding, organisation and delivery.

Breast lymphedema following breast-conserving treatment for breast cancer: current status and future directions.

To examine the current evidence on breast lymphedema (BL) diagnosis and treatment after breast-conserving surgery, identify gaps in the literature, and propose future research directions. A comprehensive literature review was conducted using Ovid, PubMed, and Cochrane, including studies published between 2000 and 2023. References were reviewed manually for eligible studies. Inclusion criteria were as follows: patients who underwent breast conserving treatment (surgery ± radiation) for breast cancer, goals of the paper included analyzing or reviewing BL measurement with ultrasound or tissue dielectric constant, or BL treatment. Twenty-seven manuscripts were included in the review. There is variation in incidence, time course, and risk factors for BL. Risk factors for BL included breast size, primary and axillary surgery extent, radiation, and chemotherapy but require further investigation. Diagnostic methods for BL currently rely on patient report and lack standardized criteria. Tissue dielectric constant (TDC) and ultrasound (US) emerged as promising ambulatory BL assessment tools; however, diagnostic thresholds and validation studies with ICG lymphography are needed to establish clinical utility. The evidence base for treatment of BL is weak, lacking high-quality studies. The natural history of BL is not well defined. TDC and US show promise as ambulatory assessment tools for BL; however, further validation with lymphatic imaging is required. BL treatment is not established in the literature. Longitudinal, prospective studies including pre-radiation measurements and validating with lymphatic imaging are required. These data will inform screening, diagnostic criteria, and evidence-based treatment parameters for patients with BL after breast-conserving surgery and radiation.

The effect of demographic and clinical data on anxiety and depression levels in breast cancer patients receiving radiotherapy.

The aim of this study is to investigate the effects of sociodemographic and clinical data on depression and anxiety levels in patients who undergoing radiotherapy for breast cancer. A total of 111 patients with breast cancer treated in the Radiation Oncology Department of Kayseri City Education and Research Hospital were included in this study. The study was planned prospectively as a survey research based study. Ethics committee approval was obtained. After obtaining the necessary consent for voluntary participation, patients were interviewed face-to-face. The research survey included the Hospital Anxiety and Depression Scale (HADS), as well as demographic and clinical information. Statistical analysis was performed with the collected data. According to the results of repeated measures analysis of variance, the mean difference between the 3-month and 6-month measurements of the depression scale values on the first day of radiotherapy was statistically significant (P &lt; 0.001). Mean differences were statistically notable for age and marital status variables in anxiety and for age, education level, marital status, employment status, family history of cancer, menopause, surgery, chemotherapy and hormone therapy variables in depression. When the change in the presence (&gt; 10 depression scale) or absence (&lt; 10 depression scale) of depression at three different times of radiotherapy (first day, 3 and 6 months) was examined, a statistically notable difference was found between the depression scale values of patients receiving radiotherapy on the first day, 3 months after radiotherapy and 6 months after radiotherapy (P &lt; 0.05). According to the results of our study, the psychological health of women with breast cancer was affected during and after radiotherapy. As a response, psychiatric counseling should be considered as a part of the treatment for depression and anxiety that occur during and after treatment in breast cancer patients.

Pulmonary Function and Lung Fibrosis up to 12 Years After Breast Cancer Radiotherapy

Breast cancer (BC) treatment may affect pulmonary function, but evidence of long-term pulmonary toxicity is scarce. This study aimed to evaluate pulmonary function, radiation fibrosis (RF), and patient-reported dyspnea up to 12 years after different BC treatment modalities. Two hundred fifty patients with BC referred to postoperative radiotherapy (RT) were included in this study. High-resolution computed tomography, pulmonary function tests (PFTs), clinical examinations, and patient-reported dyspnea were assessed before RT and at 3, 6, and 12 months and up to 12 years after RT. Vital capacity (VC), forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and diffusion capacity of the lungs for carbon monoxide (DLCO) declined at 3 months after RT and remained low at long-term follow-up except for DLCO, which increased up to 12 years after RT. VC, FEV1, and FVC changes differed between patients treated with and without chemotherapy, and FEV1 differed between patients treated with locoregional and local RT. An early decline in VC, FEV1, and FVC predicted a late decline in PFT values up to 12 years after RT (P = .020, P = .004, and P = .020, respectively). RF, mainly grade 1, was observed in 91% of patients at long-term follow-up. Few patients reported severe dyspnea at long-term follow-up, and there was no statistically significant association with concurrent RF or decline in PFT values from baseline. Chemotherapy and locoregional RT affected performance in PFTs up to 12 years after RT. Reduction in VC, FVC, and FEV1 3 months after RT predicted a decline in PFT values at long-term follow-up. However, a late decline in PFT values was not associated with long-term RF or patient-reported dyspnea.

VMAT with DIBH in hypofractionated radiotherapy for left-sided breast cancer after breast-conserving surgery: results of a non-inferiority clinical study.

The purpose of this study was to show the safety of volumetric modulated arc therapy (VMAT) with deep inspiration breath-hold (DIBH) in hypofractionated radiotherapy for left-sided breast cancer after breast-conserving surgery in a clinical setting. Twenty-five Japanese women, aged 20-59years, who were enrolled in this prospective non-inferiority study received VMAT under the condition of DIBH with 42.4Gy/16 fractions for whole-breast irradiation (WBI) ± boost irradiation for the tumor bed to show the non-inferiority of VMAT with DIBH to conventional fractionated WBI with free breathing. The primary endpoint was the rate of occurrence of radiation dermatitis of Grade 3 or higher or pneumonitis of Grade 2 or higher within 6months after the start of radiotherapy. This study was registered with UMIN00004321. All of the enrolled patients completed the planned radiotherapy without interruption. The evaluation of adverse events showed that three patients (12.0%) had Grade 2 radiation dermatitis. There was no other Grade 2 adverse event and there was no patient with an adverse event of Grade 3 or higher. Those results confirmed our hypothesis that the experimental treatment method is non-inferior compared with our historical results. There was no patient with locoregional recurrence or metastases. In conclusion, VMAT under the condition of DIBH in hypofractionated radiotherapy for left-sided breast cancer after breast-conserving surgery can be performed safely in a clinical setting.

Application research on reducing radiation-induced lung injury with a trigger operator based on overlap volume histogram (OVH) in breast cancer postoperative radiotherapy

This study aims to develop a trigger operator based on the Overlap Volume Histogram (OVH) and examined its effectiveness in enhancing plan quality to minimize radiation-induced lung injury in postoperative radiotherapy for breast cancer. This trigger operator was applied for plan re-optimization to the previous Volumetric Modulated Arc Therapy (VMAT) plans of 16 left breast conserving surgery cases. These cases were categorized into a Contiguous Group (CG) and a Separated Group (SG) based on the relative position between the target and the Left-Lung (L-Lung). We investigated the changes in Vx, mean dose, and Normal Tissue Complication Probability (NTCP) values of organs-at-risk (OARs) before and after using the trigger operator. The Pairwise Sample T test was employed to evaluate the differences in indices between the two groups before and after optimizations. The trigger operator effectively initiated plan re-optimization. The values of V5, V10, V20, V30, and V40 of the L-Lung, as well as the mean dose of the heart, all decreased after re-optimization. The Pairwise Sample T test results showed statistically significant differences in the V20, V30, and V40 of the L-Lung in the CG (P < 0.01), and in the V5, V10, V20, V30, and V40 of the L-Lung in the SG (P < 0.01). Our findings suggest that the proposed trigger operator can improve plan quality, thereby reducing radiation-induced lung injury in postoperative radiotherapy for breast cancer.

Noninvasive Red Laser Intervention before Radiotherapy of Triple-negative Breast Cancer in a Murine Model.

Radiotherapy is a well-established cancer treatment; it is estimated that approximately 52% of oncology patients will require this treatment modality at least once. However, some tumors, such as triple-negative breast cancer (TNBC), may present as radioresistant and thus require high doses of ionizing radiation and a prolonged period of treatment, which may result in more severe side effects. Moreover, such tumors show a high incidence of metastases and decreased survival expectancy of the patient. Thus, new strategies for radiosensitizing TNBC are urgently needed. Red light therapy, photobiomodulation, has been used in clinical practice to mitigate the adverse side effects usually associated with radiotherapy. However, no studies have explored its use as a radiosensitizer of TNBC. Here, we used TNBC-bearing mice as a radioresistant cancer model. Red light treatment was applied in three different protocols before a high dose of radiation (60 Gy split in 4 fractions) was administered. We evaluated tumor growth, mouse clinical signs, total blood cell counts, lung metastasis, survival, and levels of glutathione in the blood. Our data showed that the highest laser dose in combination with radiation arrested tumor progression, likely due to inhibition of GSH synthesis. In addition, red light treatment before each fraction of radiation, regardless of the light dose, improved the health status of the animals, prevented anemia, reduced metastases, and improved survival. Collectively, these results indicate that red light treatment in combination with radiation could prove useful in the treatment of TNBC.

Trends in Utilization and Medicare Spending on Short-Course Radiation Therapy for Breast and Prostate Cancer: An Episode-Based Analysis From 2015 to 2019

Evidence supports the value of shorter, similarly efficacious, and potentially more cost-effective hypofractionated radiation therapy (RT) regimens in many clinical scenarios for breast cancer (BC) and prostate cancer (PC). However, practice patterns vary considerably. We used the most recent Centers for Medicare and Medicaid Services data to assess trends in RT cost and practice patterns among episodes of BC and PC. We performed a retrospective cohort analysis of all external beam RT episodes for BC and PC from 2015 to 2019 to assess predictors of short-course RT (SCRT) use and calculated spending differences. Multivariable logistic regression defined adjusted odds ratios of receipt of SCRT over longer-course RT (LCRT) by treatment modality, age, year of diagnosis, type of practice, and the interaction between year and treatment setting. Medicare spending was evaluated using multivariable linear regression controlling for duration of RT regimen (SCRT vs LCRT) in addition to the above covariables. Of 143,729 BC episodes and 114,214 PC episodes, 63,623 (44.27%) and 25,955 (22.72%) were SCRT regimens, respectively. Median total spending for SCRT regimens among BC episodes was $9418 (interquartile range [IQR], $7966-$10,983) versus $13,602 (IQR, $11,814-$15,499) for LCRT. Among PC episodes, median total spending was $6924 (IQR, $4,509-$12,905) for stereotactic body RT, $18,768 (IQR, $15,421-$20,740) for moderate hypofractionation, and $27,319 (IQR, $25,446-$29,421) for LCRT. On logistic regression, receipt of SCRT was associated with older age among both BC and PC episodes as well as treatment at hospital-affiliated over freestanding sites (P < .001 for all). In this evaluation of BC and PC RT episodes from 2015 to 2019, we found that shorter-course RT resulted in lower costs than longer-course RT. SCRT was also more common in hospital-affiliated sites. Future research focusing on potential payment incentives encouraging SCRT when clinically appropriate in the 2 most common cancers treated with RT will be valuable as the field continues to prospectively evaluate cost-effective hypofractionation in other disease sites.

Depression and Anxiety Among English- and Spanish-Speaking Patients With Breast Cancer Receiving Radiation Therapy

An estimated 30% and 40% of patients with breast cancer experience depression and anxiety, respectively. However, distress experienced by patients with breast cancer receiving radiation therapy may vary among patients and vary at different time points. This study sought to describe the changes in levels of depression and anxiety experienced by English- and Spanish-speaking patients throughout a course of radiation therapy for breast cancer, along with the effect of different variables to better understand potential gaps. Eligibility criteria included English- and Spanish-speaking females, aged 18 or older, undergoing radiation therapy treatment for breast cancer at 2 institutions. Pre- and posttreatment surveys were completed before and after delivery of radiation therapy. Sociodemographic characteristics collected included race, ethnicity, marital status, education level, longest residency location, religion, housing, and food insecurity. The survey ended with the standardized PHQ-4 questionnaire to assess anxiety and depression. Results were analyzed using the analysis of covariance procedure. A total of 160 participants completed pre- and posttreatment surveys, with an initial response rate of 100% (169 patients), though 9 were lost to follow-up. Most of the participants were nonwhite (50%), primarily married (42.5%), and had a high school or associate's level education (46.9%). The total baseline distress mean (BDM) was 2.96 and the final distress mean was 2.78. English-speaking patients comprised 82.5% (n=132) of the sample and had a BDM of 2.91 with an adjusted change mean decrease of 0.45. Spanish-speaking patients comprised 17.5% (n=28) of the sample, with a baseline distress mean of 3.21 and an adjusted change mean increase of 1.03 (P=.002). Housing (P=.017) and food insecurity (P=.0002) also showed increasing distress with increased insecurity at baseline. Patients who speak Spanish, identify as Hispanic, or are experiencing food and housing insecurity are at an increased risk for depression and anxiety, and could benefit from more support during their course of radiation therapy to minimize distress.

Bayesian Network structure learning algorithm for highly missing and non imputable data: Application to breast cancer radiotherapy data

It is not uncommon for real-life data produced in healthcare to have a higher proportion of missing data than in other scopes. To take into account these missing data, imputation is not always desired by healthcare experts, and complete case analysis can lead to a significant loss of data. The algorithm proposed here, allows the learning of Bayesian Network graphs when both imputation and complete case analysis are not possible. The learning process is based on a set of local bootstrap learnings performed on complete sub-datasets which are then aggregated and locally optimized. This learning method presents competitive results compared to other structure learning algorithms, whatever the mechanism of missing data.

Quality assurance in a phase III, multicenter, randomized trial of POstmastectomy radioThErapy in Node posiTive breast cancer with or without Internal mAmmary nodaL irradiation (POTENTIAL): a planning benchmark case

PurposeTo report the planning benchmark case results of the POTENTIAL trial—a multicenter, randomized, phase 3 trial—to evaluate the value of internal mammary nodal (IMN) irradiation for patients with high-risk breast cancer.MethodsAll participating institutions were provided the outlines of one benchmark case, and they generated radiation therapy plans per protocol. The plans were evaluated by a quality assurance team, after which the institutions resubmitted their revised plans. The information on beams arrangement, skin flash, inhomogeneity corrections, and protocol compliance was assessed in the first and final submission.ResultsThe plans from 26 institutions were analyzed. Some major deviations were found in the first submission. The protocol compliance rates of dose coverage for the planning target volume of chest wall, supraclavicular fossa plus axilla, and IMN region (PTVim) were all significantly improved in the final submission, which were 96.2% vs. 69.2%, 100% vs. 76.9%, and 88.4% vs. 53.8%, respectively. For OARs, the compliance rates of heart Dmean, left anterior descending coronary artery V40Gy, ipsilateral lung V5Gy, and stomach V5Gy were significantly improved. In the first and final submission, the mean values of PTVim V100% were 79.9% vs. 92.7%; the mean values of heart Dmean were 11.5 Gy vs. 9.7 Gy for hypofractionated radiation therapy and 11.5 Gy vs. 11.0 Gy for conventional fractionated radiation therapy, respectively.ConclusionThe major deviations were corrected and protocol compliance was significantly improved after revision, which highlighted the importance of planning benchmark case to guarantee the planning quality for multicenter trials.

Clinical Experience of Axillary Radiotherapy for Node-positive Breast Cancer

AimsPatients with breast cancer who have positive lymph nodes are currently recommended axillary node clearance (ANC) or regional nodal irradiation (RNI). ANC is associated with complications such as lymphoedema, brachial plexopathy and shoulder stiffness. The AMAROS Group showed RNI to be non-inferior to ANC with regards to survival and recurrence, and with a better quality of life. We conducted a large real-world population study to show our centre's experience with the use of RNI and to contribute to the current discussion around the management of node-positive breast cancer. Materials and methodsWe evaluated patients who received RNI as opposed to ANC between 2006 and 2009 (n = 190). Patients had a range of cancer subtypes/grades. All had positive axillary disease, identified by axillary node sampling or sentinel lymph node biopsy. Systemic therapy was given as per standard protocol. Our data were compared with those of patients who had RNI (n = 681) in AMAROS. Patients were followed up retrospectively and overall survival, breast cancer-specific survival, distant metastasis-free survival, locoregional recurrence and toxicity were recorded, including lymphoedema, brachial plexopathy and shoulder stiffness. Survival analysis was performed on R via the Kaplan–Meier method. Univariate and multivariate analyses were also performed. Toxicity data were reported as percentages. Patients meeting POSNOC trial criteria (one to two positive sentinel lymph nodes, macrometastasis, receiving adjuvant chemotherapy) including if oestrogen receptor-positive (stratified POSNOC) were identified for subgroup analysis in the regression model. ResultsLocoregional recurrence was 3.16% versus AMAROS RNI of 1.82%. Overall survival was slightly lower in our population, but cancer-specific survival was higher than AMAROS. Lymphoedema rates were 5.8% versus AMAROS 11% in RNI and 23% in ANC arms, respectively. Brachial plexopathy was 1.6% and arm/shoulder stiffness 7.4%. AMAROS conducted a quality of life survey pertaining to arm/shoulder stiffness, mobility and function, which seemed to affect about 18% in the RNI arm. Univariate analysis revealed POSNOC status, especially if also oestrogen receptor-positive, to be a low risk group with hazard ratio 0.42 (0.20–0.83, P = 0.015). Extracapsular extension of lymph node metastasis was a poor prognostic factor; hazard ratio 4.39 (1.45–14.0, P = 0.009). ConclusionWe support the conclusion of the AMAROS trial with survival and recurrence following RNI being non-inferior to ANC, and with similarly favourable toxicity data. We support the continuing use of RNI as a treatment option for patients with node-positive breast cancer. Further research is required to answer the key questions regarding personalised management for node-positive breast cancer, with regards to de-escalation and also intensification for the patients exhibiting adverse tumour biology.

Benefit of scar boost radiation following postmastectomy radiation in female breast cancer: a retrospective analysis

Background: The use of postmastectomy radiation (PMRT) as a standard of care for female breast cancer is well established, with scar boost radiation being a discretionary choice. However, the efficacy of scar boost radiation remains a subject of debate. Methods: A retrospective analysis was conducted from medical records of female patients diagnosed with breast cancer who have undergone PMRT from January 2012 to January 2015 at Srinagarind Hospital, Khon Kaen University. The primary endpoint was chest wall local control (LC), and the secondary endpoints were risk factors associated with chest wall local recurrence (LR), locoregional recurrence (LRR) and overall survival (OS). Results: A total of 549 female patient records were included. The median follow-up time was 21 months. 31.51% of patients received scar boost radiation. The majority of the patients had ductal carcinoma (98.5%) and were histologically graded as grade 2 (44.6%) or 3 (39.0%). The estimated 10-yr chest wall local control rate was 82.14% (95% CI 68.12 - 99.04%) in scar boost group versus 93.18% (95% CI 89.58 - 96.92%) in no scar boost groups. No significant differences between the two groups were found in LR (HR 0.87, 95% CI 0.35-2.19), LRR (HR 1.20, 95% CI 0.60-2.37), and OS (HR 1.05, 95% CI 0.09-11.54). Subset analysis showed that lobular carcinoma was associated with LR and LRR (HR 11.32, 95% CI 3.24-39.54 and HR 5.65, 95% CI 1.71-18.61) while positive supraclavicular node was associated with LRR (HR 4.51, 95% CI 1.37-14.79). Scar boost radiation also resulted in a higher frequency of skin toxicity (grade 1-3), skin fibrosis (grade 1), and radiation pneumonitis (grade 1). Conclusions: There is no evidence supporting that scar boost radiation following PMRT in female breast cancer patients is superior in chest wall LC. Scar boost radiation is also statistically significantly associated with increased toxicity.

A quality assurance framework for routine monitoring of deep learning cardiac substructure computed tomography segmentation models in radiotherapy.

For autosegmentation models, the data used to train the model (e.g., public datasets and/or vendor-collected data) and the data on which the model is deployed in the clinic are typically not the same, potentially impacting the performance of these models by a process called domain shift. Tools to routinely monitor and predict segmentation performance are needed for quality assurance. Here, we develop an approach to perform such monitoring and performance prediction for cardiac substructure segmentation. To develop a quality assurance (QA) framework for routine or continuous monitoring of domain shift and the performance of cardiac substructure autosegmentation algorithms. A benchmark dataset consisting of computed tomography (CT) images along with manual cardiac substructure delineations of 241 breast cancer radiotherapy patients were collected, including one "normal" image domain of clean images and five "abnormal" domains containing images with artifact (metal, contrast), pathology, or quality variations due to scanner protocol differences (field of view, noise, reconstruction kernel, and slice thickness). The QA framework consisted of an image domain shift detector which operated on the input CT images and a shape quality detector on the output of an autosegmentation model, and a regression model for predicting autosegmentation model performance. The image domain shift detector was composed of a trained denoising autoencoder (DAE) and two hand-engineered image quality features to detect normal versus abnormal domains in the input CT images. The shape quality detector was a variational autoencoder (VAE) trained to estimate the shape quality of the auto-segmentation results. The output from the image domain shift and shape quality detectors was used to train a regression model to predict the per-patient segmentation accuracy, measured by Dice coefficient similarity (DSC) to physician contours. Different regression techniques were investigated including linear regression, Bagging, Gaussian process regression, random forest, and gradient boost regression. Of the 241 patients, 60 were used to train the autosegmentation models, 120 for training the QA framework, and the remaining 61 for testing the QA framework. A total of 19 autosegmentation models were used to evaluate QA framework performance, including 18 convolutional neural network (CNN)-based and one transformer-based model. When tested on the benchmark dataset, all abnormal domains resulted in a significant DSC decrease relative to the normal domain for CNN models ( ), but only for some domains for the transformer model. No significant relationship was found between the performance of an autosegmentation model and scanner protocol parameters ( ) except noise ( ). CNN-based autosegmentation models demonstrated a decreased DSC ranging from 0.07 to 0.41 with added noise, while the transformer-based model was not significantly affected (ANOVA, ). For the QA framework, linear regression models with bootstrap aggregation resulted in the highest mean absolute error (MAE) of , in predicted DSC (relative to true DSC between autosegmentation and physician). MAE was lowest when combining both input (image) detectors and output (shape) detectors compared to output detectors alone. A QA framework was able to predict cardiac substructure autosegmentation model performance for clinically anticipated "abnormal" domain shifts.

Do Barrier Films Impact Long-Term Skin Toxicity following Whole-Breast Irradiation? Objective Follow-Up of Two Randomised Trials.

Purpose: Hydrofilm, a polyurethane-based barrier film, can be used to prevent acute radiation dermatitis (RD) in adjuvant whole-breast irradiation (WBI) for breast cancer. This cost-effective prophylactic measure is currently being recommended to a growing number of patients, yet long-term safety data and its impact on late radiation-induced skin toxicity such as pigmentation changes and fibrosis have not been investigated. Methods: We objectively evaluated patients who were previously enrolled in either of two intrapatient-randomised (lateral versus medial breast halve) controlled trials on the use of Hydrofilm for RD prevention (DRKS00029665; registered on 19 July 2022). Results: Sixty-two patients (47.7% of the initial combined sample size) provided consent for this post-hoc examination, with a median follow-up time (range) of 58 (37-73) months. Following WBI, there was a significant increase in yellow skin tones of the entire breast when compared to baseline measurements before WBI (p < 0.001) and a significant increase of cutis, subcutis, and oedema thickness (p < 0.001, p < 0.001, and p = 0.004, respectively). At follow-up, there were no significant differences in either pigmentation changes or skin fibrosis between the Hydrofilm and standard of care breast halves. Conclusion: These data suggest that Hydrofilm can be safely used in the context of acute RD prevention, without affecting late side effects, supporting its widespread use.

Is FAST FORWARD the Way Forward in Radiotherapy for Locally Advanced Breast Cancer – Learnings From the COVID Pandemic

IntroductionLow middle-income countries (LMICs), including India, have paucity of external beam radiotherapy (RT) machines leading to prolonged wait times for RT. Delay in delivery of RT has been shown to adversely affect outcomes in locally advanced breast cancer (LABC). With the availability of results of multiple randomized controlled trials, hypofractionated RT delivered over 3 to 4 weeks became the standard of care in breast cancer RT. MethodsWe conducted a retrospective audit of 172 LABC patients treated with ultrahypofractionated adjuvant RT (radiotherapy completed in 1 week) during the COVID pandemic. Log rank and Cox-regression model used for univariate and multi-variate analyses. ResultsNo patient developed grade 3 esophagitis. Grade 2 esophagitis requiring short term narcotic analgesics was seen in 12 (6.9%) patients. Grade 2 or higher toxicity peaked between 2 and 3 weeks after RT. The estimated 2 and 3- year recurrence free survival (RFS) for the cohort is 87.1 % and 81.4 %, respectively. The estimated 2 and 3-year overall survival for the cohort is 95% and 91.3%. On multivariate analysis, presence of extra-nodal extension was found to be an independent factor associated with worse RFS (P = .028). ConclusionsFAST FORWARD protocol RT in LABC appears well tolerated.