Radiotherapy For Breast Cancer Research Articles

Editorial Comment to: Lung-heart Toxicity in a Randomized Clinical Trial of Hypofractionated Image-guided Radiation Therapy for Breast Cancer

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Factors influencing pathological complete response and tumor regression in neoadjuvant radiotherapy and chemotherapy for high-risk breast cancer

BackgroundPathological complete response (pCR) is a well-established prognostic factor in breast cancer treated with neoadjuvant systemic therapy (naST). The determining factors of pCR are known to be intrinsic subtype, proliferation index, grading, clinical tumor and nodal stage as well as type of systemic therapy. The addition of neoadjuvant radiotherapy (naRT) to this paradigm might improve response, freedom from disease, toxicity and cosmetic outcome compared to adjuvant radiotherapy. The factors for pCR and primary tumor regression when neoadjuvant radiation therapy is added to chemotherapy have not been thoroughly described.MethodsWe performed a retrospective analysis of 341 patients (cT1-cT4/cN0-N+) treated with naRT and naST between 1990 and 2003. Patients underwent naRT to the breast and mostly to the supra-/infraclavicular lymph nodes combined with an electron or brachytherapy boost. NaST was given either sequentially or simultaneously to naRT using different regimens. We used the univariate and multivariate regression analysis to estimate the effect of different subgroups and treatment modalities on pCR (ypT0/Tis and ypN0) as well as complete primary tumor response (ypT0/Tis; bpCR) in our cohort. Receiver operating characteristic (ROC) analysis was performed to evaluate the interval between radiotherapy (RT) and resection (Rx) as well as radiotherapy dose.ResultsOut of 341 patients, pCR and pbCR were achieved in 31% and 39%, respectively. pCR rate was influenced by resection type, breast cancer subtype, primary tumor stage and interval from radiation to surgery in the multivariate analysis. Univariate analysis of bpCR showed age, resection type, breast cancer subtype, clinical tumor stage and grading as significant factors. Resection type, subtype and clinical tumor stage remained significant in multivariate analysis. Radiation dose to the tumor and interval from radiation to surgery were not significant factors for pCR. However, when treatment factors were added to the model, a longer interval from radiotherapy to resection was a significant predictor for pCR.ConclusionsThe factors associated with pCR following naST and naRT are similar to known factors after naST alone. Longer interval to surgery might to be associated with higher pCR rates. Dose escalation beyond 60 Gy did not result in higher response rates.

Outcomes of Radiotherapy in Oligoprogressive Breast Cancer

Introduction: Radiotherapy (RT) shows potential for improving local control in cases of oligoprogressive metastatic breast cancer (mBC). This retrospective analysis aims to evaluate the advantages of RT in such a clinical scenario. Methods: We conducted a retrospective analysis including patients with mBC who received radiation therapy (RT) for up to three sites of oligoprogression while continuing systemic therapy. The study took place between January 2014 and December 2021. Our endpoints were progression-free survival after radiotherapy (PFS-AR), the rate of discontinuation of systemic therapy (RDT) at three months post-RT, and overall survival (OS). We used Cox regression analysis to perform multivariate analysis for PFS-AR. Results: Fifty-nine patients met the inclusion criteria. The PFS-AR was 13 months (95% CI 8.5–18.8 months). At three months, the RDT was 3% (two patients). A significant difference in median PFS-AR was observed between patients in the first + second-line group and those in the subsequent line group (p = 0.03). In the multivariate analysis conducted for PFS-AR, the biologically effective dose (BED) with α/β = 4 > 100 Gy emerged as the sole significant variable (p = 0.0017). The median overall survival (OS) was 24.4 months (95% CI 17–24.4 months). Conclusions: This study is the first report on the outcomes of radiotherapy in a cohort of over 50 patients with oligoprogressive metastatic breast cancer (mBC). Our findings emphasize the significant relationship between PFS-AR, the number of ongoing lines of systemic therapy, and the BED of radiotherapy.

Palliative Radiotherapy for Symptomatic Primary Tumors in Patients With Locally Advanced Breast Cancer.

Breast cancer remains a significant health concern for women, with a significant number of women facing unresectable, symptomatic, and advanced disease that severely affects their quality of life. Palliative radiotherapy (RT) is a well-established modality for managing such cases and alleviating symptoms. Recent advancements in systemic therapies and the resulting increase in long-term survival rates have not only heightened the need for retreatment in certain patients, but have also emphasized the importance of achieving durable local control. Additionally, inconsistencies in RT referral timing and variations in disease severity and extent contribute to diverse RT objectives and expected outcomes. The optimal dose fractionation for RT remains underexplored. Furthermore, a deeper understanding of breast radiobiology, along with the introduction of ultra- and moderately hypofractionated regimens and the widespread adoption of conformal techniques such as intensity-modulated RT, has diversified the approaches in RT dose and target volume. This review aimed to provides a comprehensive summary of the current evidence on the efficacy, outcomes, and toxicity profiles of palliative RT for symptomatic breast cancer. It highlights the need for more optimized regimens and further research to address the evolving treatment landscape and differing expectations of patients and physicians regarding RT.

Validation of Spanish-Language Surveys Utilized for the Navigator-Assisted Hypofractionation (NAVAH) Program to Aid Hispanic-American Breast Cancer Patients.

Cancer accounts for 22% of all mortality and is the leading cause of death among Hispanic and/or Latinx patients in the United States. The disparities in access to radiation therapy (RT), mortality rates, and treatment outcomes among Hispanic-American breast cancer patients compared with other populations highlight the urgent need for targeted interventions. The Navigator-Assisted Hypofractionation (NAVAH) program, with its innovative patient navigation approach and culturally sensitive survey, aims to better identify the specific barriers faced by this population. This study is a report of the NAVAH program experience piloting a Spanish-language culturally sensitive survey in Hispanic-American volunteers. Hispanic-American volunteers with fluency in Spanish were recruited to participate in survey conduction, identified from local networks. Survey information was assessed by topic category, and survey responses were amalgamated into a representative score for each category. Survey categories include acceptability (comfort and prejudice among interactions with the system), accessibility (transportation, distance to care, and health care literacy), accommodation (access to the internet, navigating transportation), affordability (financial considerations, employment, and level of education), and availability (access to a medical center, coordinating care, and overall quality of care). A total of 6 volunteers meeting inclusion criteria completed the survey; 4 in person and 2 by telephone. The median survey completion time was 12 minutes 38 seconds. Respondents noted satisfaction and trust in their interactions with medical providers; however, responses in the acceptability category highlighted a high perception of disparities in the medical system, including a high prevalence of racial and ethnic prejudice and a high prevalence of treatment differences between high-income and low-income patients in clinical settings. In the first Spanish-language survey of its kind, our findings indicate that this survey design is feasible in the Hispanic-American population. Implementation of this survey in breast cancer patients will provide more definitive and comprehensive answers regarding other categories in the survey, including financial challenges during treatment, access to accommodations, and perception of treatment during cancer care. The investigation involving patients actively receiving breast cancer RT is currently underway.

A feasibility study of dosimetry for breast cancer radiotherapy based on body surface changes.

The requirement for precise and effective delivery of the actual dose to the patient grows along with the complexity of breast cancer radiotherapy. Dosimetry during treatment has become a crucial component of guaranteeing the efficacy and security. To propose a dosimetry method during breast cancer radiotherapy based on body surface changes. A total of 29 left breast cancer radiotherapy cases were retroactively retrieved from an earlier database for analysis. Non-rigid image registration and dose recalculation of the planning computed tomography (CT) referring to the Cone-beam computed tomography were performed to obtain dose changes. The study used 3D point cloud feature extraction to characterize body surface changes. Based on the correlation proof, a mapping model is developed between body surface changes and dose changes using neural network framework. The MSE metrics, the Euclidean distances of feature points and the 3D gamma pass rate metric were used to assess the prediction accuracy. A strong correlation exist between body surface changes and dose changes (first canonical correlation coefficient=0.950). For the dose deformation field and dose amplitude difference in the test set, the MSE of the predicted and actual values were 0.136 pixels and 0.229 cGy, respectively. After deforming the planning dose into a deformed one, the feature points' Euclidean distance between it and the recalculated dose changes from 9.267±1.879mm to 0.456±0.374mm. The 3D gamma pass rate of 90% or higher for the 2mm/2% criteria were achieved by 80.8% of all cases, with a minimum pass rate of 75.9% and a maximum pass rate of 99.6%. Pass rate for the 3mm/2% criteria ranged from 87.8% to 99.8%, with 92.3% of the cases having a pass rate of 90% or higher. This study provides a dosimetry method that is non-invasive, real-time, and requires no additional dose for breast cancer radiotherapy.

Scar Decompression in Managing Breast Cancer-Related Lymphedema: Is it Needed?

Mastectomy, axillary lymph node dissection, and irradiation for breast cancer commonly result in perivascular and axillary scarring. This scarring is thought to cause functional venous stenosis that leads to downstream venous hypertension in the affected extremity. Standard surgical practice is to decompress perivascular scarring at the time of physiologic lymphedema surgery in patients with breast cancer-related lymphedema (BCRL). However, it is unknown whether this scar release influences surgical outcomes. The purpose of this study is to evaluate prevalence of functional venous stenosis in patients with BCRL and determine whether scar decompression is a necessary step in physiologic lymphedema surgery. The authors conducted a retrospective review of 64 patients with unilateral BCRL that presented to our lymphedema center between January 2020 and October 2022. Radiologist reports of venous duplex ultrasound for the bilateral upper extremities identified any disturbances in venous flow or indications of venous stenosis. Of the 64 patients with BCRL, 78% (n=50) had prior axillary lymph node dissection. Forty-seven (73%) patients completed ultrasound imaging, of which, one patient (2%) had venous stenosis in the affected lymphedematous extremity identified on duplex ultrasound that may have suggested functional scarring. Vascularized lymph node transfer (VLNT) without scar decompression was performed in six patients (9%). Average preoperative lymphedema life impact scale (LLIS) and L-dex scores were 35 and 19 units, with a mean decrease of 23 (67%) and 6 (30%) units postoperatively. Most patients with BCRL did not have identifiable functional venous stenosis on duplex ultrasound, apart from one patient with suspected post-thrombotic changes. All six patients that received VLNT without scar decompression had a successful outcome with decreased measures of lymphedema postoperatively. Scar decompression may therefore be unnecessary in physiologic lymphedema surgery, reducing operative times and avoiding risk of injury to neurovascular structures of the axilla.

Concurrent Use of Trastuzumab Deruxtecan and Radiation Therapy in HER2-positive and HER2-low Metastatic Breast Cancer: A Single-center Experience and Review of the Literature.

Recent DESTINY-Breast trials have demonstrated trastuzumab deruxtecan's effectiveness in HER2-positive and HER2-low metastatic breast cancer. However, safety concerns remain regarding its combination with radiation therapy (RT). The purpose of this work is to assess the toxicity profile of combining trastuzumab deruxtecan and RT in patients with HER2-positive and HER2-low metastatic breast cancer to address these concerns. We conducted a retrospective study which included patients treated at Institut Curie Paris between November 2020 and January 2024. Patients with HER2-positive and HER2-low metastatic breast cancer who received concurrent trastuzumab deruxtecan and RT were identified. Data on patient demographics, treatment regimens, radiation doses, toxicity profiles, and treatment discontinuations were collected. Follow-up was conducted from the last day of radiotherapy until death or the last examination and toxicities were graded using the CTCAE V5.0. The studied population includes all 33 patients with HER2-positive and HER2-low metastatic breast cancer who underwent concurrent treatment with trastuzumab deruxtecan and radiotherapy. The median follow-up was 11 months. The most common acute grade 1 toxicity was nausea. Grade 2 toxicities affected 21.2% of patients, including asthenia, mucositis, cardiac decompensation, and diarrhea. Trastuzumab deruxtecan discontinuation occurred in 5 patients due to systemic treatment-related toxicities, including nausea, thrombocytopenia, neutropenia, and cardiac decompensation. There were 21.2% reported with late toxicities, with nausea being the most prevalent. Our series of patients who received concurrent treatment of radiotherapy and trastuzumab deruxtecan are showing acceptable toxicity. Larger prospective studies are needed to evaluate the toxicity and efficacy of this combination.

Preliminary Experience with a Cleansing Mousse and a Non-Steroidal Emulsion for the Prevention and Treatment of Acute Radiation Dermatitis in Breast Cancer Patients Undergoing Adjuvant Radiotherapy

Background: Radiation dermatitis (RD) is the most frequent side effect in patients undergoing adjuvant radiotherapy (RT) for breast cancer. Despite the skin-sparing benefits of new RT techniques, most patients develop RD. There is currently no standard treatment to prevent and soothe RD, which is generally managed with emollients, moisturizers, or corticosteroids. We conducted a prospective observational study to evaluate the rate and grade of RD with the application of a cleansing mousse and a non-steroidal emulsion during the adjuvant RT program in patients with breast cancer submitted to surgery. Materials and Methods: A cleansing mousse containing vegetable glycerin (12%), phytoextract of chamomile (0.5%), yarrow phytoextract (0.5%), sweet almond (0.1%), Oenothera oil (0.1%), and rice protein hydrolyzate (0.1%), and an emulsion containing micronized zinc oxide (3.7%), rapeseed phytosterols (1.7%), aloe (0.5%), 18-beta glycyrrhetinic acid (0.5%), alpha bisabolol (0.5%), and zanthalene (0.5%) were offered to breast cancer patients undergoing adjuvant RT to prevent the onset of RD and mitigate its severity. These specific ingredients were selected for their well-known anti-inflammatory, antioxidant, and moisturizing properties. Skin toxicities were recorded photographically and graded according to the RTOG scoring system. Results: From March 2023 to July 2023, a total of 24 patients with a median age of 59 years (range 42–75) were enrolled. Halfway through the RT treatment, 20 patients (83.3%) had G0 skin toxicity, three (12.5%) G1, one (4.2%) G2. None showed G3–G4 toxicity. At the end of RT, seven patients (29.2%) exhibited G0 skin toxicity, 14 (58.3%) G1, two (8.3%) G2, one (4.2%) G3. No patient developed G4 toxicity. Fifteen days after the end of RT, 13 patients (54.2%) had G0 skin toxicity, 10 (41.1%) G1, one (4.2%) G2, with none showing G3–G4 toxicity. Conclusions: Our data suggest that the tested topicals might be an effective option for preventing and alleviating RD. Further prospective randomized studies are needed to confirm our findings.

Post-Operative Radiation in Early Breast Cancer with N1 Disease: 10-Year Follow-Up.

Post-operative radiotherapy for post-menopausal women with early breast cancer and N1 disease is controversial. Although locoregional control is improved, overall survival (OS) benefit is unclear. The clinical benefit of post-operative irradiation in this group of patients over 10 years was reviewed. We aimed to evaluate the OS, disease-free survival (DFS), and factors affecting OS and DFS. A retrospective review of 191 post-menopausal women with early breast cancer and N1 disease from 2004 to 2011 was performed. Demographics, post-operative histology, adjuvant treatment, OS, and DFS were evaluated. Post-operative radiation was given to 95 of 191 women (49.7%). Younger age at diagnosis (p < 0.001), a greater number of involved nodes (p = 0.004), lymphovascular invasion (LVI), and a higher tumor grade (p = 0.001) were more likely in women who received post-operative radiation. Nodal radiation did not improve 10-year DFS (p = 0.084) or OS (p = 0.203). Post-operative nodal radiation was associated with significant improvement in 10-year OS in women who received only hormonal therapy (p = 0.047) and no other systemic therapy. Women with unfavorable risk factors were more likely to receive post-operative radiation, likely due to a perceived higher risk of recurrence. Nodal radiation did not significantly improve 10-year DFS or OS in early breast cancer patients with N1 disease, and the benefit was not clearly demonstrated. However, in those who were on hormonal therapy, radiotherapy was beneficial in improving overall survival.

Laterality of Radiation Therapy in Breast Cancer is Not Associated with Increased Risk for Coronary Artery Disease in the Contemporary Era

BackgroundExternal beam radiation therapy (EBRT) is a critical component of breast cancer (BC) therapy. Given the improvement in technology in the contemporary era, we hypothesize there is no difference the development of or worsening of existing coronary artery disease (CAD) in patients with BC receiving left vs right sided radiation. MethodsFor the meta-analysis portion of our study, we searched PubMed, Web of Science, and Scopus and included studies from January 1999 to September 2022. CAD was identified using a homogenous metric across multiple studies included. We computed the risk ratio (RR) for included studies using a random effects model. For the institutional cohort portion of our study, we selected high cardiovascular risk patients diagnosed with BC between 2010-2022 if they met our inclusion criteria. We performed a Cox proportional hazards model with stepwise adjustment. ResultsA pooled random effects model with 9 studies showed that patients with left-sided BC receiving EBRT had a 10% increased risk of CAD when compared to patients with right-sided BC receiving EBRT (RR: 1.10, 95% CI: 1.02 - 1.18, p = 0.01). However, subgroup analysis of 6 studies that included patients diagnosed after 1980 did not show a significant difference in CAD based on BC laterality (RR: 1.07, 95% CI: 0.95 – 1.20, p = 0.27). For the institutional cohort portion of the study, we found that patients with left-sided BC who received EBRT did not have a significantly higher risk for CAD when compared to their right-sided counterparts (HR = 0.73, 95% CI: 0.34 - 1.54, p = 0.402). ConclusionOur study suggests a historical trend of increased CAD in BC patients receiving left-sided EBRT. Data from patients diagnosed after 2010 in our institutional cohort did not show a significant difference, emphasizing that modern EBRT regimens are safe, and laterality of BC does not affect CAD outcomes in the short term after a breast cancer diagnosis.

Dosimetric Study and Robustness Analysis of Base Note Intensive Locked Field Radiotherapy for Left Breast Cancer.

The locked vision plan can make the left breast cancer heart and lung organs dose. The aim of the present study was to compare the dosimetric differences between field-locked and field-split plans in intensity-modulated radiotherapy for left-sided breast cancer, to explore the effect of field-locking on the low-dose region, and to evaluate its robustness to the radiotherapy target, in order to provide a reference for the selection of clinical radiotherapy protocols. A total of 30 patients were selected after radical left breast cancer surgery, and 7-field locked-field and split-field plans were developed to compare the dose difference (∆D) between the target area and each organ at risk, and to introduce offsets of 3, 5 and 7 mm in six directions and recalculate the perturbed dose distributions, and to compare the ∆D between the original and the perturbed plans according to the robustness of the plans. The results revealed that the D98%, D95% and Dmean values of the planning target volume (PTV) of the two plans differed little and were not statistically different. The locked field plan provided better protection for the left lung, right lung, heart, right breast and left anterior descending coronary artery. For PTV∆D98%, PTV∆D95%, PTV∆Dmean, the ∆D was higher for the Locked Fields plan, and for LungL∆5, LungL∆20 and Heart∆mean, the ∆D was higher for the original plan. It was concluded that the field-locking plan could reduce the low-dose area of the affected lung and provide improved protection to the remaining critical organs, and the field-locking plan was more robust in protecting critical organs. Meanwhile, the field-locking plan showed higher sensitivity to positional deviation for target PTV.

Personalized Deep Learning Model for Clinical Target Volume on Daily Cone-beam Computed Tomography in Breast Cancer Patients

PurposeHerein, we developed a deep learning algorithm to improve the segmentation of the clinical target volume (CTV) on daily cone-beam computed tomography (CBCT) scans in breast cancer radiotherapy. By leveraging the Intentional Deep Overfit Learning (IDOL) framework, we aimed to enhance personalized image-guided radiotherapy (IGRT) based on patient-specific learning. MethodsWe utilized 240 CBCT scans from 100 breast cancer patients and employed a two-stage training approach. The first stage involved training a novel general deep learning model (Swin UNETR, UNET, and SegResNET) on 90 patients. The second stage utilized intentional overfitting on the remaining 10 patients for patient-specific CBCT outputs. Quantitative evaluation was conducted using the Dice Similarity Coefficient (DSC), Hausdorff Distance (HD), mean surface distance (MSD), and independent samples t-test with expert contours on CBCT scans from the 1st to 15th fractions. ResultsIDOL integration significantly improved CTV segmentation, particularly with the Swin UNETR model (p-values <0.05). Using patient-specific data, IDOL enhanced the DSC, HD, and MSD metrics. The average DSC for the 15th fraction improved from 0.9611 to 0.9819, the average HD decreased from 4.0118 mm to 1.3935 mm, and the average MSD decreased from 0.8723 to 0.4603. Incorporating CBCT scans from the initial treatments and 1st to 3rd fractions further improved results, with an average DSC of 0.9850, an average HD of 1.2707 mm, and an average MSD of 0.4076 for the 15th fraction, closely aligned with physician-drawn contours. ConclusionCompared with a general model, our patient-specific deep learning-based training algorithm significantly improved CTV segmentation accuracy of CBCT scans in patients with breast cancer. This approach, coupled with continuous deep learning training using daily CBCT scans, demonstrated enhanced CTV delineation accuracy and efficiency. Future studies should explore the adaptability of the IDOL framework to diverse deep learning models, datasets, and cancer sites.

Role of AURKB Inhibition in Reducing Proliferation and Enhancing Effects of Radiotherapy in Triple-Negative Breast Cancer.

Breast cancer is a leading cause of cancer-related deaths in females. Triple-negative breast cancer (TNBC) subtype is the most aggressive form of breast cancer that lacks biomarkers and effective targeted therapies. Its high degree of heterogeneity as well as innate and acquired resistance to treatment creates further barriers in achieving positive clinical outcomes in TNBC. Thus, development of novel treatment approaches in TNBC is of high clinical significance. Multimodality approaches with targeted agents and radiotherapy (RT) are promising for increasing efficacy of treatment and circumventing resistance. Here we examined anticancer effects of the Aurora Kinase B (AURKB) inhibitor AZD1152 as a single agent and in combination with RT using various TNBC cell lines, MDA-MB-468, MDA-MB-231 and SUM-159. We observed that AZD1152 alone effectively inhibited colony formation in TNBC cell lines. The combination of AZD1152 at IC50 concentrations together with ionizing radiation further reduced colony formation as compared to the single agent treatment. Our data support the notion that inhibition of the AURKB pathway is a promising strategy for treatment and radiosensitization of TNBC and warrants further translational studies.

Role of AURKB Inhibition in Reducing Proliferation and Enhancing Effects of Radiotherapy in Triple-Negative Breast Cancer

Role of AURKB Inhibition in Reducing Proliferation and Enhancing Effects of Radiotherapy in Triple-Negative Breast Cancer

Ultrahypofractionation in postoperative radiotherapy for breast cancer: A single-institution retrospective cohort series.

The 'FAST-forward', study published in April 2020, demonstrated the effectiveness of an extremely hypofractionated radiotherapy schedule, delivering the total radiation dose in five sessions over the course of 1 week. We share our department's experience regarding patients treated with this regimen in real-world clinical settings, detailing outcomes related to short-term toxicity and efficacy. A descriptive observational study was conducted on 160 patients diagnosed with breast cancer. Between July 2020 and December 2021, patients underwent conservative surgery followed by a regimen of 26 Gy administered in five daily fractions. The median age was 64 years (range: 43-83), with 82 patients (51.3%) treated for left-sided breast cancer, 77 patients (48.1%) for right-sided breast cancer, and 1 instance (0.6%) of bilateral breast cancer. Of these, 66 patients had pT1c (41.3%), 70.6% were infiltrative ductal carcinomas, and 11.3% were ductal carcinoma insitu. Most tumours exhibited intermediate grade (41.9%), were hormone receptor positive (81.3%), had low Ki-67 (Ki-67 < 20%; 51.9%) and were Her 2 negative (85%). The majority of surgical margins were negative (99.4%). Among the patients, 72.5% received hormonotherapy, and 23.8% received chemotherapy. Additionally, 26 patients (16.3%) received an additional tumour boost following whole breast irradiation (WHBI) of 10 Gy administered in five sessions of 2 Gy over a week. The median planning target volume (PTV) was 899 cm3 (range: 110-2509 cm3). Early toxicity was primarily grade I radiodermatitis, affecting 117 patients (73.1%). During a median follow-up of 15 months (range: 3.9-28.77), only one patient experienced a local relapse, which required mastectomy. The implementation of this highly hypofractionated regimen in early-stage breast cancer appears feasible and demonstrates minimal early toxicity. However, a more extended follow-up duration would be required to evaluate long-term toxicity and efficacy accurately.

Echocardiographic Functional Outcomes Following Regional Nodal Irradiation for Breast Cancer Using Volumetric Modulated Arc Therapy

Echocardiographic Functional Outcomes Following Regional Nodal Irradiation for Breast Cancer Using Volumetric Modulated Arc Therapy

Hypofractionated versus Conventional Postmastectomy Irradiation for Breast Cancer: Comparison of Acute Skin Toxicity.

Breast cancer is the leading cause of cancer mortality among women. Radiotherapy can reduce recurrence and prolong survival of patients accepting breast-conserving surgery (BCS). This study aims to compare acute skin reactions in patients receiving hypofractionated versus conventional radiotherapy at a single institution and to summarize the relevant influencing factors. This study analyzed 152 patients who underwent either hypofractionated or conventional whole-breast irradiation (WBI) after BCS. Acute skin toxicity was assessed according to the Radiation Therapy Oncology Group (RTOG) criteria. Predictive factors for acute skin toxicity were identified using multivariate analysis and visualized using a forest spot. Grade 0 reactions occurred in 75.34% vs 70.89%, grade 1 in 16.44% vs 15.19%, grade 2 in 8.22% vs 12.66%, and grade 3 in 0% vs 1.27% of patients receiving hypofractionated and conventional WBI, respectively. There was no statistically significant difference in acute skin reaction in patients treated with hypofractionated radiation compared with conventional radiation (P = 0.62). Multivariate analysis revealed that metastatic lymph nodes (P = 0.021), whole-breast planning target volume (PTV-WB) (P < 0.001), and tumor bed planning target volume (PTV-TB) (P = 0.002) were significantly correlated with higher rates of acute skin toxicity. Hypofractionated WBI demonstrated similar acute skin adverse reactions compared to conventional WBI. These findings indicate that hypofractionated radiotherapy offers comparable tolerance, equivalent curative effect, convenience, andeconomic benefits, supporting its clinicalpromotion.

Dosimetric risk factors for radiation esophagitis in patients with breast cancer following regional nodal radiation

BACKGROUND Radiation esophagitis (RE) is one of the most common clinical symptoms of regi-onal lymph node radiotherapy for breast cancer. However, there are fewer studies focusing on RE caused by hypofractionated radiotherapy (HFRT). AIM To analyze the clinical and dosimetric factors that contribute to the development of RE in patients with breast cancer treated with HFRT of regional lymph nodes. METHODS Between January and December 2022, we retrospectively analysed 64 patients with breast cancer who met our inclusion criteria underwent regional nodal intensity-modulated radiotherapy at a radiotherapy dose of 43.5 Gy/15F. RESULTS Of the 64 patients in this study, 24 (37.5%) did not develop RE, 29 (45.3%) developed grade 1 RE (G1RE), 11 (17.2%) developed grade 2 RE (G2RE), and none developed grade 3 RE or higher. Our univariable logistic regression analysis found G2RE to be significantly correlated with the maximum dose, mean dose, relative volume 20-40, and absolute volume (AV) 20-40. Our stepwise linear regression analyses found AV30 and AV35 to be significantly associated with G2RE (P &lt; 0.001). The optimal threshold for AV30 was 2.39 mL [area under the curve (AUC): 0.996; sensitivity: 90.9%; specificity: 91.1%]. The optimal threshold for AV35 was 0.71 mL (AUC: 0.932; sensitivity: 90.9%; specificity: 83.9%). CONCLUSION AV30 and AV35 were significantly associated with G2RE. The thresholds for AV30 and AV35 should be limited to 2.39 mL and 0.71 mL, respectively.

Concurrent Use of Abemaciclib and Radiotherapy in Metastatic Breast Cancer Patients: A Single-Center Experience.

There is little evidence regarding the safety and efficacy of the combination of abemaciclib plus radiotherapy (RT). The majority of studies investigated the combination of RT with palbociclib or ribociclib reporting that hematological toxicity is common. Given the unique toxicity profile of abemaciclib with greater gastrointestinal toxicity compared to hematological toxicity, we wanted to evaluate the toxicity of the combination with RT in metastatic breast cancer (BC) patients. Patients with histologically proven metastatic or locally advanced BC treated with RT and concurrent abemaciclib were selected. Toxicity was assessed according to the NCI-CTCAE V4.0. Thirty-two metastatic sites were treated in 19 patients and analyzed. All patients received abemaciclib during the RT course. A total of 68% of patients received a full dose of abemaciclib during RT. Also, 71.9% of patients received a palliative intent (median dose = 30 Gy, range = 8-30 Gy), and 26.3% were treated for 9 oligo-metastatic or oligo-progressive sites of disease with stereotactic body RT (median dose = 30 Gy, range 21-30 Gy, given in 3-5 fractions). Overall, the rate of G3 toxicity was 15.7%. The rate of G3 hematological toxicity was 10.6% (2/19 patients, one G3 neutropenia and one G3 anemia). No patient presented diarrhea, including those treated for RT sites close to the bowel. One patient developed G3 skin toxicity. Pain significantly improved after RT (mean value NRS pre-RT = 3.9, SD = 3.07; mean value NRS after RT = 0.9, SD = 0.46; p &lt; 0.0001). Abemaciclib and concomitant RT seem well tolerated showing acceptable toxicity.