Radiotherapy For Breast Cancer Research Articles

Locoregional Ablative Radiation Therapy for Patients With Breast Cancer Unsuitable for Surgical Resection

Breast cancer patients unsuitable for surgical resection are typically managed with palliative systemic therapy alone. We report outcomes of 5-fraction ablative radiotherapy for non-resected breast cancers. Retrospective analysis of an institutional registry of breast cancer patients unsuitable for resection who underwent 35-40 Gy/5 fractions to the primary breast tumour and/or regional lymph nodes from 2014-2021. Primary outcomes were cumulative incidence of local failure (LF) and grade ≥3 toxicity (CTCAE v5.0). We reviewed 57 patients who received 61 treatment courses (median age of 81 years, range 38-99). Unresectable tumour (10%), patient refusal (18%), medical inoperability (35%), and metastatic disease (37%) were the causes of not having surgery. Five patients (8%) had previously undergone adjuvant locoregional radiotherapy. Fifty-four percent (n=33/61) of treatment courses targeted the breast only, 31% (n=19/61) both the breast and lymph nodes, and 15% (n=9/61) the lymph nodes only. Sixty-seven percent (n=35/52) of the courses that targeted the breast were delivered with partial breast irradiation and 33% (n=17/52) with whole breast radiotherapy (median dose of 25Gy in 5 fractions) ± simultaneous integrated boost to the primary tumour. Most primary tumours (65%, n=34/52) and target lymph nodes (61%, n=17/28) were treated with a dose of 35 Gy in 5 fractions. Most treatments (52%) were delivered with intensity-modulated radiotherapy (IMRT). Radiotherapy was delivered daily (20%), every other day (18%), twice weekly (36%) or weekly (26%). The 2-year cumulative incidence of LF was 11.4% and grade≥3 toxicity was 15.1%. The grade ≥3 toxicity was 6.5% for IMRT treatments, versus 7.7% for non-IMRT treatments targeting partial breast and/or lymph nodes (HR 1.13, P=0.92), versus 38.9% for non-IMRT treatments targeting the entire breast (HR 6.91, P=0.023). All grade ≥3 toxicity cases were radiation dermatitis. No cases of brachial plexopathy were observed. 35-40 Gy in 5 fractions is a safe and effective breast stereotactic body radiotherapy regimen and may be an attractive option for patients who are not surgical candidates. Highly conformal techniques (i.e. IMRT or partial breast irradiation) were associated with a reduced risk of toxicity and should be the preferred treatment approaches.

Intraoperative Radiation Therapy Delivered by Brachytherapy in Breast Cancer: An Interim Analysis of a Phase 2 Trial

PurposeIntraoperative breast cancer radiotherapy (IORT) offers an alternative to external beam radiotherapy (EBRT) after breast-conserving surgery (BCS). The Intraoperative brachytherapy (IOBT) trial applies high dose rate (HDR) brachytherapy with a new applicator prototype as IORT after BCS. In this interim analysis of the IOBT trial, we present the oncological safety and toxicity of the method MethodsEligible patients were women, ≥ 50 years old with an unifocal nonlobular, estrogen-receptor-positive, HER2-negative breast cancer, cN0, ≤ 3 cm, treated with BCS and sentinel node biopsy (SNB). Toxicity was registered according to the LENT-SOMA scale. Cumulative incidence of local (LR) and regional recurrence (RR) were calculated through cumulative incidence function whereas overall survival (OS) was illustrated through Kaplan–Meier curve. ResultsUntil February 2023, 155 women (median age 68 years) were included in the trial. Twenty-nine women (18.7%) received supplemental EBRT, mostly due to positive SNB. Three-year cumulative incidence of LR and RR were 1.0% (CI 95 % 0.1%-2.3%) and 2.1% (CI 95% 0.8%-4.2%) respectively. Five- year cumulative incidence of LR and RR were 3.9% (CI 95% 1.8%-6.4%) and 2.1% (CI 95% 0.8%-4.2%) respectively. Five-year OS was 96.3% (CI 95% 93.6%-98.4%). Side effects were limited, low grade, and transient. ConclusionAcknowledging the short median follow-up time at interim analysis, our initial results indicate that delivering IORT through HDR brachytherapy in carefully selected breast cancer patients is feasible and oncological safe so far. A long-term follow-up is essential to confirm the initial results.

Evaluation of the theranostic characteristics of chitosan-decorated bismuth oxide nanoparticles conjugated curcumin and 5-aminolevulinic acid as a biocompatible targeted nanoplatform in CT and breast cancer radiation therapy

Developing safe and effective multifunctional nanomaterials for cancer therapy is crucial. A highly effective contrast agent is necessary for optimal results in CT scans during radiotherapy.we synthesized bismuth oxide using the sol-gel method, coated it with chitosan, and added layers of 5-aminolevulinic acid and curcumin. The curcumin in the nano complex makes it ideal for targeted applications.Bi2O3/CS@5-ALA-CUR NPs with a size of about 80 nm and exceptional stability were synthesized and fully characterized through FTIR, XRD, DLS, and TEM analysis. An MTT assay showed that Bi2O3/CS@5-ALA-CUR NPs had the highest cytotoxicity at 160 μg/mL with radiation after 48 h incubation time on SKBr-3 cells, with no significant cytotoxicity on normal cells. Bi2O3/CS@5-ALA-CUR NPs increased the generation of reactive oxygen species (ROS) and enhanced radiosensitization effects by up to 450 %. SKBr-3 cells were CT scanned after 48 h incubation with 400 μM concentration, revealing the highest X-ray attenuation at 80 kVp. Bi2O3/CS@5-ALA-CUR NP injection and 2 Gy radiation exposure at 6 MV significantly reduced tumor size in female BALB/c mice compared to controls.These exciting findings suggest that Bi2O3/CS@5-ALA-CUR nanoparticles have immense potential as theranostic agents for diagnosing and treating tumors, with the added benefit of being guided by CT imaging during radiotherapy.

Large institutional experience of early outcomes and dosimetric findings with postoperative stereotactic partial breast irradiation in breast cancer

PurposeTo analyze the dosimetric and toxicity outcomes of patients treated with postoperative stereotactic partial breast irradiation (S-PBI). MethodsWe identified 799 women who underwent S-PBI at our institution between January 2016 and December 2022. The most commonly used dose-fraction and technique were 30 Gy in 5 fractions (91.7 %) and a robotic stereotactic radiation system with real-time tracking (83.7 %). The primary endpoints were dosimetric parameters and radiation-related toxicities. For comparison, a control group undergoing ultra-hypofractionated whole breast irradiation (UF-WBI, n = 468) at the same institution was selected. ResultsA total of 815 breasts from 799 patients, with a median planning target volume (PTV) volume of 89.6 cm3, were treated with S-PBI. Treatment plans showed that the mean and maximum doses received by the PTV were 96.2 % and 104.8 % of the prescription dose, respectively. The volume of the ipsilateral breast that received 50 % of the prescription dose was 32.3 ± 8.9 %. The mean doses for the ipsilateral lung and heart were 2.5 ± 0.9 Gy and 0.65 ± 0.39 Gy, respectively. Acute toxicity occurred in 175 patients (21.5 %), predominantly of grade 1. Overall rate of late toxicity was 4 % with a median follow-up of 31.6 months. Compared to the UF-WBI group, the S-PBI group had comparably low acute toxicity (21.5 % vs. 25.2 %, p = 0.12) but significantly lower dosimetric parameters for all organs-at-risks (all p < 0.05). ConclusionIn this large cohort, S-PBI demonstrated favorable dosimetric and toxicity profiles. Considering the reduced radiation exposure to surrounding tissues, external beam PBI with advanced techniques should at least be considered over traditional WBI-based approaches for PBI candidates.

Cardiac structure, function, and coronary anatomy 10 years after isolated contemporary adjuvant radiotherapy in breast cancer patients with low cardiovascular baseline risk.

The effects of isolated contemporary low-dose breast cancer (BC) radiotherapy (RT) on the heart remain poorly understood. This study aims to assess the long-term impacts of BC-RT on cardiac structure and function. Seventy-six women (62 ± 7 years) without history of prior heart disease, who had undergone RT for either first left (n = 36) or right (n = 40) BC, without additional medical oncology therapy apart from hormonal treatment 11 ± 1 years earlier, underwent transthoracic echocardiography, cardiac magnetic resonance imaging (CMR), computed tomography coronary angiography (CTCA), NT-proBNP, and a 6-min walk test (6MWT). They were compared with 54 age-matched healthy female controls. By CTCA, 68% of BC patients exhibited no or very mild coronary disease, while only 11% had moderate stenosis (50-69%) and 3% had significant stenosis (>70%). Despite slightly reduced regional echocardiographic midventricular strains, BC patients exhibited similar global left and right ventricular volumes, ejection fractions, and global strains by echocardiography and CMR as controls. Mitral E/e' ratios were slightly higher, and mitral deceleration times were slightly lower, but NT-proBNP was similar to controls. Also, 6MWT was normal. None had late gadolinium enhancement, and extracellular volume fraction was similar in BC (28 ± 3 vs. 29 ± 3, P = 0.15) and controls. No differences were observed relative to dose or side of RT. Aside from minor alterations of regional strains and diastolic parameters, women who received isolated RT for BC had low prevalence of coronary disease, normal global systolic function, NT-proBNP, and exercise capacity and showed no structural changes by CMR, refuting significant long-term cardiotoxicity in such low-risk patients.

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.

Retracted: Value Analysis of Neoadjuvant Radiotherapy for Breast Cancer after Modified Radical Mastectomy Based on Data Mining.

[This retracts the article DOI: 10.1155/2022/6257536.].

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.