Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 20 de 18.301
1.
Radiat Oncol ; 19(1): 68, 2024 May 31.
Article En | MEDLINE | ID: mdl-38822369

BACKGROUND: Approximately 25-50% of patients undergoing radiotherapy (RT) experience psychological distress and anxiety, which can detrimentally affect both their quality of life and treatment outcomes. While previous research has demonstrated that relaxation exercises can enhance the tolerability of RT and alleviate associated stress and anxiety, the specific needs for such therapies in radiation oncology remain under-explored. This study aims to investigate the demand for and preferences toward relaxation exercises among radiotherapy patients, addressing a critical gap in patient-centered care. METHODS: A prospective pseudonymized survey study using a one-time paper-based questionnaire was conducted from 2022 to 2023 among patients undergoing curative-intent RT for breast cancer or patients undergoing palliative RT for bone metastases. Patients were asked in a 11-item questionnaire about their anxiety, pre-existing practice of relaxation exercises/interventions, their interest in relaxation exercises, and preferences on the type and format of instruction. Data were analyzed descriptively. RESULTS: 100 patients (74 female and 26 male) responded, of whom 68 received curative-intent adjuvant RT and 32 palliative RT. Median age was 62 years. 78% of patients indicated a desire to be actively involved in their radiotherapy, but only 27% had used relaxation exercises prior to RT. 44.8% of both curatively and palliatively treated patients who wanted to be actively involved in their therapy desired to learn how to best relax. 56.4% of respondents were willing to spend extra time learning offered exercises. CONCLUSION: The survey indicates that patients undergoing RT, both for curative or palliative intent, desire relaxation exercises to relieve stress and anxiety from RT. It is therefore important to assess the need for relaxation interventions in individual patients and to develop suitable programs or collaborate with other healthcare professionals to meet these needs.


Breast Neoplasms , Relaxation Therapy , Humans , Female , Middle Aged , Breast Neoplasms/radiotherapy , Breast Neoplasms/pathology , Breast Neoplasms/psychology , Male , Prospective Studies , Aged , Surveys and Questionnaires , Adult , Quality of Life , Aged, 80 and over , Anxiety/etiology , Palliative Care , Bone Neoplasms/secondary , Bone Neoplasms/radiotherapy , Bone Neoplasms/psychology , Exercise Therapy/methods
2.
Front Immunol ; 15: 1373497, 2024.
Article En | MEDLINE | ID: mdl-38720889

Introduction: Intraoperative radiation therapy (IORT) delivers a single accelerated radiation dose to the breast tumor bed during breast-conserving surgery (BCS). The synergistic biologic effects of simultaneous surgery and radiation remain unclear. This study explores the cellular and molecular changes induced by IORT in the tumor microenvironment and its impact on the immune response modulation. Methods: Patients with hormone receptor (HR)-positive/HER2-negative, ductal carcinoma in situ (DCIS), or early-stage invasive breast carcinoma undergoing BCS with margin re-excision were included. Histopathological evaluation and RNA-sequencing in the re-excision tissue were compared between patients with IORT (n=11) vs. non-IORT (n=11). Results: Squamous metaplasia with atypia was exclusively identified in IORT specimens (63.6%, p=0.004), mimicking DCIS. We then identified 1,662 differentially expressed genes (875 upregulated and 787 downregulated) between IORT and non-IORT samples. Gene ontology analyses showed that IORT was associated with the enrichment of several immune response pathways, such as inflammatory response, granulocyte activation, and T-cell activation (p<0.001). When only considering normal tissue from both cohorts, IORT was associated with intrinsic apoptotic signaling, response to gamma radiation, and positive regulation of programmed cell death (p<0.001). Using the xCell algorithm, we inferred a higher abundance of γδ T-cells, dendritic cells, and monocytes in the IORT samples. Conclusion: IORT induces histological changes, including squamous metaplasia with atypia, and elicits molecular alterations associated with immune response and intrinsic apoptotic pathways. The increased abundance of immune-related components in breast tissue exposed to IORT suggests a potential shift towards active immunogenicity, particularly immune-desert tumors like HR-positive/HER2-negative breast cancer.


Breast Neoplasms , Immunomodulation , Intraoperative Care , Mastectomy, Segmental , Tumor Microenvironment , Humans , Female , Breast Neoplasms/radiotherapy , Breast Neoplasms/immunology , Breast Neoplasms/pathology , Middle Aged , Tumor Microenvironment/immunology , Tumor Microenvironment/radiation effects , Immunomodulation/radiation effects , Aged , Adult , Combined Modality Therapy
3.
Radiat Oncol ; 19(1): 62, 2024 May 27.
Article En | MEDLINE | ID: mdl-38802888

BACKGROUND: The effectiveness and safety of moderately hypofractionated radiotherapy (HFRT) in patients undergoing breast-conserving surgery (BCS) has been demonstrated in several pivotal randomized trials. However, the feasibility of applying simultaneous integrated boost (SIB) to the tumor bed and regional node irradiation (RNI) using modern radiotherapy techniques with HFRT needs further evaluation. METHODS: This prospective, multi-center, randomized controlled, non-inferiority phase III trial aims to determine the non-inferiority of HFRT combined with SIB (HFRTsib) compared with conventional fractionated radiotherapy with sequential boost (CFRTseq) in terms of five-year locoregional control rate in breast cancer patients undergoing upfront BCS. A total of 2904 participants will be recruited and randomized in a 1:1 ratio into the HFRTsib and CFRTseq groups. All patients will receive whole breast irradiation, and those with positive axillary nodes will receive additional RNI, including internal mammary irradiation. The prescribed dose for the HFRTsib group will be 40 Gy in 15 fractions, combined with a SIB of 48 Gy in 15 fractions to the tumor bed. The CFRTseq group will receive 50 Gy in 25 fractions, with a sequential boost of 10 Gy in 5 fractions to the tumor bed. DISCUSSION: This trial intends to assess the effectiveness and safety of SIB combined with HFRT in early breast cancer patients following BCS. The primary endpoint is locoregional control, and the results of this trial are expected to offer crucial evidence for utilizing HFRT in breast cancer patients after BCS. TRIAL REGISTRATION: This trial was registered at ClincalTrials.gov (NCT04025164) on July 18, 2019.


Breast Neoplasms , Mastectomy, Segmental , Radiation Dose Hypofractionation , Humans , Breast Neoplasms/radiotherapy , Breast Neoplasms/surgery , Breast Neoplasms/pathology , Female , Prospective Studies , Adult , Middle Aged , Aged , Radiotherapy, Intensity-Modulated/methods , Radiotherapy, Adjuvant/methods , Young Adult
4.
Asian Pac J Cancer Prev ; 25(5): 1559-1566, 2024 May 01.
Article En | MEDLINE | ID: mdl-38809627

INTRODUCTION: Circulating tumor cells (CTCs) and Programmed death-ligand 1 (PD-L1) play pivotal roles in cancer biology and therapy response. This exploratory study aimed to elucidate the influence of neoadjuvant radiotherapy on PD-L1 expression in tumor tissues and CTCs of patients with inoperable locally advanced breast cancer. METHODS: We conducted a prospective cohort study at Universitas Andalas Hospital Padang from January to December 2022 with 27 patients. Biopsies and blood draws were executed before and after the tenth fractions of neoadjuvant radiotherapy. Following radiotherapy, CTCs were isolated using magnetic beads enrichment, followed by an RT-PCR analysis for PD-L1 expression. Correlations between PD-L1 expression and tumor response, evaluated via local response and RECIST criteria before and after radiotherapy breast CT scan, were examined using Fisher's exact and chi-square tests. RESULTS: Our data revealed no significant alterations in PD-L1 expression in either tumor tissues or CTCs during radiotherapy (p=0.848 for tissue, p=0.548 for CTCs). Notably, PD-L1 expression in tumor tissue before treatment was significantly associated with RECIST (p=0.021), while other correlations with local response and RECIST were not statistically significant. CONCLUSION: The study implies radiotherapy may not significantly influence PD-L1 expression in tumor tissue and CTCs. However, pre-treatment PD-L1 expression in tumor tissue correlates with RECIST criteria. These findings highlight the need for additional, comprehensive studies to elucidate further the interplay between PD-L1, CTCs, and radiotherapy response.


B7-H1 Antigen , Biomarkers, Tumor , Breast Neoplasms , Neoplastic Cells, Circulating , Humans , B7-H1 Antigen/metabolism , Neoplastic Cells, Circulating/metabolism , Neoplastic Cells, Circulating/pathology , Neoplastic Cells, Circulating/radiation effects , Female , Prospective Studies , Breast Neoplasms/radiotherapy , Breast Neoplasms/pathology , Breast Neoplasms/metabolism , Middle Aged , Biomarkers, Tumor/metabolism , Biomarkers, Tumor/blood , Follow-Up Studies , Prognosis , Aged , Adult , Neoadjuvant Therapy
5.
Phys Med Biol ; 69(11)2024 May 30.
Article En | MEDLINE | ID: mdl-38729212

Objective.Online adaptive radiotherapy (OART) is a promising technique for delivering stereotactic accelerated partial breast irradiation (APBI), as lumpectomy cavities vary in location and size between simulation and treatment. However, OART is resource-intensive, increasing planning and treatment times and decreasing machine throughput compared to the standard of care (SOC). Thus, it is pertinent to identify high-yield OART candidates to best allocate resources.Approach.Reference plans (plans based on simulation anatomy), SOC plans (reference plans recalculated onto daily anatomy), and daily adaptive plans were analyzed for 31 sequential APBI targets, resulting in the analysis of 333 treatment plans. Spearman correlations between 22 reference plan metrics and 10 adaptive benefits, defined as the difference between mean SOC and delivered metrics, were analyzed to select a univariate predictor of OART benefit. A multivariate logistic regression model was then trained to stratify high- and low-benefit candidates.Main results.Adaptively delivered plans showed dosimetric benefit as compared to SOC plans for most plan metrics, although the degree of adaptive benefit varied per patient. The univariate model showed high likelihood for dosimetric adaptive benefit when the reference plan ipsilateral breast V15Gy exceeds 23.5%. Recursive feature elimination identified 5 metrics that predict high-dosimetric-benefit adaptive patients. Using leave-one-out cross validation, the univariate and multivariate models classified targets with 74.2% and 83.9% accuracy, resulting in improvement in per-fraction adaptive benefit between targets identified as high- and low-yield for 7/10 and 8/10 plan metrics, respectively.Significance.This retrospective, exploratory study demonstrated that dosimetric benefit can be predicted using only ipsilateral breast V15Gy on the reference treatment plan, allowing for a simple, interpretable model. Using multivariate logistic regression for adaptive benefit prediction led to increased accuracy at the cost of a more complicated model. This work presents a methodology for clinics wishing to triage OART resource allocation.


Breast Neoplasms , Machine Learning , Radiotherapy Planning, Computer-Assisted , Humans , Breast Neoplasms/radiotherapy , Radiotherapy Planning, Computer-Assisted/methods , Female , Radiosurgery/methods
6.
Arch Dermatol Res ; 316(6): 223, 2024 May 24.
Article En | MEDLINE | ID: mdl-38787423

Treatments for breast cancer can have an array of adverse effects, including hair loss, scarring, and irritated skin. These physical outcomes can, in turn, lead to body image concerns, anxiety, and depression. Fortunately, there is growing evidence that certain cosmetic therapies can improve patient self-image. Here we review various cosmetic treatment options including hair camouflage, eyebrow and eyelash camouflage, treatments for hirsutism, nipple and areola tattooing, post-mastectomy scar tattooing, treatments for dry skin/xerosis, removal of post-radiation telangiectasias, and lightening of post-radiation hyperpigmentation. For each patient concern, we report potential procedures, clinical evidence of impact on quality of life, special considerations, and safety concerns. This article aims to equip dermatologists with resources so that they may effectively counsel breast cancer survivors who express treatment-related cosmetic concerns.


Breast Neoplasms , Quality of Life , Humans , Breast Neoplasms/therapy , Breast Neoplasms/surgery , Breast Neoplasms/radiotherapy , Female , Cosmetic Techniques/adverse effects , Mastectomy/adverse effects , Body Image/psychology , Cicatrix/etiology , Cicatrix/psychology , Cicatrix/therapy , Cancer Survivors/psychology , Tattooing/adverse effects
7.
Radiat Oncol ; 19(1): 59, 2024 May 21.
Article En | MEDLINE | ID: mdl-38773616

PURPOSE: Malignant phyllodes tumor of the breast (MPTB) is a rare type of breast cancer, with an incidence of less than 1%. The value of adjuvant radiotherapy (RT) for MPTB has been controversial. The aim of the study was to explore the effect of radiotherapy on the long-term survival of female patients with MPTB at different ages. METHODS: Female MPTB patients were selected from the Surveillance, Epidemiology, and End Results (SEER) database between 2000 and 2020. A Kaplan-Meier survival analysis was conducted to investigate the value of RT for the long-term survival of MPTB patients in different age groups. Additionally, univariate and multivariate Cox regression analyses were performed for overall survival (OS) and breast cancer-specific survival (BCSS) of MPTB patients. Furthermore, propensity score matching (PSM) was also performed to balance the differences in baseline characteristics. RESULTS: 2261 MPTB patients were included in this study, including 455 patients (20.12%) with RT and 1806 patients (79.88%) without RT. These patients were divided into four cohorts based on their ages: 18-45, 46-55, 56-65, and 65-80. Before adjustment, there was a statistically significant difference in long-term survival between RT-treated and non-RT-treated patients in the younger age groups (age group of 18-45 years: OS P = 0.019, BCSS P = 0.016; age group of 46-55 years: OS P < 0.001, BCSS P < 0.001). After PSM, no difference was found in long-term survival of patients in both younger and older groups regardless of whether they received RT (age group of 18-45 years: OS P = 0.473, BCSS P = 0.750; age group of 46-55 years: OS P = 0.380, BCSS P = 0.816, age group of 56-65 years: OS P = 0.484, BCSS P = 0.290; age group of 66-80 years: OS P = 0.997, BCSS P = 0.763). In multivariate COX regression analysis, RT did not affect long-term survival in patients with MPTB. CONCLUSION: There is no evidence that long-term survival of MPTB patients in specific age groups can benefit from RT.


Breast Neoplasms , Phyllodes Tumor , SEER Program , Humans , Female , Middle Aged , Breast Neoplasms/radiotherapy , Breast Neoplasms/mortality , Breast Neoplasms/pathology , Phyllodes Tumor/radiotherapy , Phyllodes Tumor/mortality , Phyllodes Tumor/pathology , Adult , Radiotherapy, Adjuvant/mortality , Retrospective Studies , Aged , Young Adult , Adolescent , Aged, 80 and over , Age Factors , Survival Rate
8.
Rev Med Liege ; 79(S1): 56-61, 2024 May.
Article Fr | MEDLINE | ID: mdl-38778651

To accept the toxic side effects of any treatment, whether medical, surgical or radiotherapeutic, cannot be avoided but implies to evaluate them taking into account the severity and prognosis of the disease that is concerned. Screening, preventing and treatment of these side effects are an integral aspect of the treatment of cancers. We will here review the contribution of the cardio-oncology, a recently emerged medical specialty. Cardiac irradiation cannot be avoided when treating several cancers, most frequently left sided breast cancer. As soon as radiotherapy is considered, it is of prime importance to evaluate each patient's risk factors and to handle them. If technical progresses have led to the complete disappearance of acute side effects of radiotherapy, this is not true for the delayed ones that may occur many years after the irradiation. Hence the need for «red flags¼ and for a systematic follow-up. Cardiac complications of left breast irradiation concern all aspects of cardiology: diseases of cardiac rhythm, valvulopathies, heart failure, coronary and pericardial disorders.


Admettre les effets secondaires d'un traitement, qu'il soit médical, chirurgical ou radiothérapique, est inévitable, mais impose de les évaluer en intégrant la gravité de l'affection pour laquelle ils sont prescrits. Leur dépistage, leur prévention et leur prise en charge font partie intégrante du traitement d'un cancer. Dans cette revue, nous ferons la synthèse de l'apport à cette démarche d'une discipline récente, la cardio-oncologie. L'irradiation cardiaque est incontournable lors du traitement de plusieurs cancers au premier rang desquels le cancer du sein gauche. Dès qu'elle est envisagée, il est essentiel d'évaluer les facteurs de risque de chaque patient et d'organiser leur prise en charge éventuelle. En effet, si les progrès techniques ont permis la disparition des complications cardiaques aiguës de la radiothérapie, ce n'est encore pas le cas des complications différées qui peuvent survenir de nombreuses années après l'irradiation. D'où la nécessité de «drapeaux rouges¼ et d'un suivi régulier systématique. Ces complications, rarement isolées, concernent tous les aspects de la cardiologie : troubles du rythme, valvulopathies, insuffisance cardiaque, maladies coronaires et atteintes péricardiques.


Cardiotoxicity , Radiotherapy , Humans , Breast Neoplasms/radiotherapy , Cardiotoxicity/prevention & control , Cardiotoxicity/etiology , Follow-Up Studies , Heart Diseases/prevention & control , Heart Diseases/etiology , Neoplasms/radiotherapy , Radiation Injuries/prevention & control , Radiation Injuries/etiology , Radiotherapy/adverse effects , Female
9.
J Therm Biol ; 121: 103859, 2024 Apr.
Article En | MEDLINE | ID: mdl-38714147

Plasmonic photothermal therapy (PPTT) is a potential technique to treat tumors selectively. However, during PPTT, issue of high temperature region and damage to the surrounding healthy is still need to be resolved. Also, treatment of deeper tumors non-invasively is a challenge for PPTT. In this paper, the effect of periodic irradiation and incident beam radius (relative to tumor size) for various gold nanorods (GNRs) concentrations is investigated to avoid much higher temperatures region with limiting thermal damage to the surrounding healthy tissue during PPTT of subsurface breast tumors located at various depths. Lattice Boltzmann method is used to solve Pennes' bioheat model to compute the resulting photothermal temperatures for the subsurface tumor embedded with GNRs subjected to broadband near infrared radiation of intensity 1 W/cm2. Computation revealed that low GNRs concentration leads to uniform internal heat generation than higher GNRs concentrations. The results show that deeper tumors, due to attenuation of incident radiation, show low temperature rise than shallower tumors. For shallower tumors situated 3 mm deep, 70% irradiation period resulted in around 20 °C reduction (110 °C-90 °C) of maximum temperature than that with the continuous irradiation. Moreover, 70% beam radius (i.e., beam radius as 70% of the tumor radius) causes less thermal damage to the nearby healthy tissue than 100% beam radius (i.e., beam radius equal to the tumor radius). The thermal damage within the healthy tissue is minimized to the 1 mm in radial direction and 3 mm in axial direction for 70% beam radius with 70% irradiation period. Overall, periodic heating and changing beam radius of the incident irradiation lead to reduce high temperature and limit healthy tissue damage. Hence, discussed results are useful for selection of the irradiation parameters for PPTT of sub-surface tumors.


Gold , Nanotubes , Photothermal Therapy , Photothermal Therapy/methods , Humans , Female , Breast Neoplasms/radiotherapy , Breast Neoplasms/therapy , Models, Biological , Infrared Rays/therapeutic use
10.
Eur J Med Res ; 29(1): 282, 2024 May 12.
Article En | MEDLINE | ID: mdl-38735974

BACKGROUND: Radiation induced acute skin toxicity (AST) is considered as a common side effect of breast radiation therapy. The goal of this study was to design dosiomics-based machine learning (ML) models for prediction of AST, to enable creating optimized treatment plans for high-risk individuals. METHODS: Dosiomics features extracted using Pyradiomics tool (v3.0.1), along with treatment plan-derived dose volume histograms (DVHs), and patient-specific treatment-related (PTR) data of breast cancer patients were used for modeling. Clinical scoring was done using the Common Terminology Criteria for Adverse Events (CTCAE) V4.0 criteria for skin-specific symptoms. The 52 breast cancer patients were grouped into AST 2 + (CTCAE ≥ 2) and AST 2 - (CTCAE < 2) toxicity grades to facilitate AST modeling. They were randomly divided into training (70%) and testing (30%) cohorts. Multiple prediction models were assessed through multivariate analysis, incorporating different combinations of feature groups (dosiomics, DVH, and PTR) individually and collectively. In total, seven unique combinations, along with seven classification algorithms, were considered after feature selection. The performance of each model was evaluated on the test group using the area under the receiver operating characteristic curve (AUC) and f1-score. Accuracy, precision, and recall of each model were also studied. Statistical analysis involved features differences between AST 2 - and AST 2 + groups and cutoff value calculations. RESULTS: Results showed that 44% of the patients developed AST 2 + after Tomotherapy. The dosiomics (DOS) model, developed using dosiomics features, exhibited a noteworthy improvement in AUC (up to 0.78), when spatial information is preserved in the dose distribution, compared to DVH features (up to 0.71). Furthermore, a baseline ML model created using only PTR features for comparison with DOS models showed the significance of dosiomics in early AST prediction. By employing the Extra Tree (ET) classifiers, the DOS + DVH + PTR model achieved a statistically significant improved performance in terms of AUC (0.83; 95% CI 0.71-0.90), accuracy (0.70), precision (0.74) and sensitivity (0.72) compared to other models. CONCLUSIONS: This study confirmed the benefit of dosiomics-based ML in the prediction of AST. However, the combination of dosiomics, DVH, and PTR yields significant improvement in AST prediction. The results of this study provide the opportunity for timely interventions to prevent the occurrence of radiation induced AST.


Breast Neoplasms , Machine Learning , Humans , Female , Breast Neoplasms/radiotherapy , Middle Aged , Adult , Aged , Skin/radiation effects , Skin/pathology , Radiation Injuries/etiology , Radiation Injuries/diagnosis , Radiotherapy Dosage
11.
Front Immunol ; 15: 1355130, 2024.
Article En | MEDLINE | ID: mdl-38742103

Pre-operative radiation therapy is not currently integrated into the treatment protocols for breast cancer. However, transforming immunological "cold" breast cancers by neoadjuvant irradiation into their "hot" variants is supposed to elicit an endogenous tumor immune defense and, thus, enhance immunotherapy efficiency. We investigated cellular and immunological effects of sub-lethal, neoadjuvant irradiation of ER pos., HER2 pos., and triple-negative breast cancer subtypes in-vitro and in-vivo in humanized tumor mice (HTM). This mouse model is characterized by a human-like immune system and therefore facilitates detailed analysis of the mechanisms and efficiency of neoadjuvant, irradiation-induced "in-situ vaccination", especially in the context of concurrently applied checkpoint therapy. Similar to clinical appearances, we observed a gradually increased immunogenicity from the luminal over the HER2-pos. to the triple negative subtype in HTM indicated by an increasing immune cell infiltration into the tumor tissue. Anti-PD-L1 therapy divided the HER2-pos. and triple negative HTM groups into responder and non-responder, while the luminal HTMs were basically irresponsive. Irradiation alone was effective in the HER2-pos. and luminal subtype-specific HTM and was supportive for overcoming irresponsiveness to single anti-PD-L1 treatment. The treatment success correlated with a significantly increased T cell proportion and PD-1 expression in the spleen. In all subtype-specific HTM combination therapy proved most effective in diminishing tumor growth, enhancing the immune response, and converted non-responder into responder during anti-PD-L1 therapy. In HTM, neoadjuvant irradiation reinforced anti-PD-L1 checkpoint treatment of breast cancer in a subtype -specific manner. According to the "bench to bedside" principle, this study offers a vital foundation for clinical translating the use of neoadjuvant irradiation in the context of checkpoint therapy.


B7-H1 Antigen , Immune Checkpoint Inhibitors , Neoadjuvant Therapy , Receptor, ErbB-2 , Triple Negative Breast Neoplasms , Animals , Female , Triple Negative Breast Neoplasms/immunology , Triple Negative Breast Neoplasms/radiotherapy , Triple Negative Breast Neoplasms/therapy , Neoadjuvant Therapy/methods , Mice , Humans , Receptor, ErbB-2/metabolism , Immune Checkpoint Inhibitors/therapeutic use , Immune Checkpoint Inhibitors/pharmacology , Cell Line, Tumor , Receptors, Estrogen/metabolism , Disease Models, Animal , Xenograft Model Antitumor Assays , Breast Neoplasms/immunology , Breast Neoplasms/radiotherapy , Breast Neoplasms/therapy
18.
Biomed Phys Eng Express ; 10(4)2024 May 17.
Article En | MEDLINE | ID: mdl-38714180

Radiotherapy (RT) is one of the major treatment modalities among surgery and chemotherapy for carcinoma breast. The surface dose study of modified reconstructive constructive Mastectomy (MRM) breast is important due to the heterogeneity in the body contour and the conventional treatment angle to save the lungs and heart from the radiation. These angular entries of radiation beam cause an unpredictable dose deposition on the body surface, which has to be monitored. Thermoluminescent dosimeter (TLD) or optically stimulated luminescent dosimeter (nano OSLD) are commonly preferable dosimeters for this purpose. The surface dose response of TLD and nano OSLD during MRM irradiation has been compared with the predicted dose from the treatment planning system (TPS). The study monitored 100 MRM patients by employing a total 500 dosimeters consisting of TLD (n = 250) and nano OSLD (n = 250), during irradiation from an Elekta Versa HD 6 MV Linear accelerator. The study observed a variance of 3.9% in the dose measurements for TLD and 3.2% for nano OSLD from the planned surface dose, with a median percentage dose of 44.02 for nano OSLD and 40.30 for TLD (p value 0.01). There was no discernible evidence of variation in dose measurements attributable to differences in field size or from patient to patient. Additionally, no variation was observed in dose measurements when comparing the placement of the dosimeter from central to off-centre positions. In comparison, a minor difference in dose measurements were noted between TLD and nano OSLD, The study's outcomes support the applicability of both TLD and nano OSLD as effective dosimeters during MRM breast irradiation for surface dose evaluation.


Breast Neoplasms , Mastectomy , Radiotherapy Dosage , Thermoluminescent Dosimetry , Humans , Female , Thermoluminescent Dosimetry/methods , Breast Neoplasms/radiotherapy , Breast Neoplasms/surgery , Radiotherapy Planning, Computer-Assisted/methods , Optically Stimulated Luminescence Dosimetry/methods , Middle Aged , Radiation Dosage , Adult , Breast/radiation effects , Breast/surgery
19.
Radiat Oncol ; 19(1): 66, 2024 May 29.
Article En | MEDLINE | ID: mdl-38811994

OBJECTIVES: Accurate segmentation of the clinical target volume (CTV) of CBCT images can observe the changes of CTV during patients' radiotherapy, and lay a foundation for the subsequent implementation of adaptive radiotherapy (ART). However, segmentation is challenging due to the poor quality of CBCT images and difficulty in obtaining target volumes. An uncertainty estimation- and attention-based semi-supervised model called residual convolutional block attention-uncertainty aware mean teacher (RCBA-UAMT) was proposed to delineate the CTV in cone-beam computed tomography (CBCT) images of breast cancer automatically. METHODS: A total of 60 patients who undergone radiotherapy after breast-conserving surgery were enrolled in this study, which involved 60 planning CTs and 380 CBCTs. RCBA-UAMT was proposed by integrating residual and attention modules in the backbone network 3D UNet. The attention module can adjust channel and spatial weights of the extracted image features. The proposed design can train the model and segment CBCT images with a small amount of labeled data (5%, 10%, and 20%) and a large amount of unlabeled data. Four types of evaluation metrics, namely, dice similarity coefficient (DSC), Jaccard, average surface distance (ASD), and 95% Hausdorff distance (95HD), are used to assess the model segmentation performance quantitatively. RESULTS: The proposed method achieved average DSC, Jaccard, 95HD, and ASD of 82%, 70%, 8.93, and 1.49 mm for CTV delineation on CBCT images of breast cancer, respectively. Compared with the three classical methods of mean teacher, uncertainty-aware mean-teacher and uncertainty rectified pyramid consistency, DSC and Jaccard increased by 7.89-9.33% and 14.75-16.67%, respectively, while 95HD and ASD decreased by 33.16-67.81% and 36.05-75.57%, respectively. The comparative experiment results of the labeled data with different proportions (5%, 10% and 20%) showed significant differences in the DSC, Jaccard, and 95HD evaluation indexes in the labeled data with 5% versus 10% and 5% versus 20%. Moreover, no significant differences were observed in the labeled data with 10% versus 20% among all evaluation indexes. Therefore, we can use only 10% labeled data to achieve the experimental objective. CONCLUSIONS: Using the proposed RCBA-UAMT, the CTV of breast cancer CBCT images can be delineated reliably with a small amount of labeled data. These delineated images can be used to observe the changes in CTV and lay the foundation for the follow-up implementation of ART.


Breast Neoplasms , Cone-Beam Computed Tomography , Radiotherapy Planning, Computer-Assisted , Humans , Cone-Beam Computed Tomography/methods , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/radiotherapy , Breast Neoplasms/pathology , Female , Radiotherapy Planning, Computer-Assisted/methods , Uncertainty , Image Processing, Computer-Assisted/methods , Algorithms
...