International multidisciplinary consensus on the integration of radiotherapy with new systemic treatments for breast cancer: European Society for Radiotherapy and Oncology (ESTRO)-endorsed recommendations

Early toxicity of moderately hypofractionated radiation therapy in breast cancer patients receiving locoregional irradiation: First results of the UNICANCER HypoG-01 phase III trial

PURPOSE

To investigate early adverse events (AEs) in HypoG-01, a randomised, controlled, multicentre, non-inferiority phase 3 trial comparing toxicity and efficacy of adjuvant loco-regional moderately hypofractionated radiation therapy versus 2 Gy daily radiation therapy.

METHODS

Women ≥ 18 years with T1-3 N0-3 M0 breast cancer were randomised 1:1 after surgery +/- systemic therapy to receive either 40 Gy/15 fractions (3-week-RT) or 50 Gy/25 fractions (5-week-RT) +/-tumour-bed boost. AEs at baseline, end of treatment, and 6-month follow-up were graded using CTCAEV4.0, LENT/SOMA and Harris 4-point scales. Competing risk analysis for cumulative incidence of AEs, worst grade dermatitis according to risk factors, and cosmetic assessment were performed in the intention-to-treat (ITT) population.

RESULTS

From September 2016 to March 2020, 29 sites enrolled 1265 women. The ITT population included 1260 patients (3-week-RT: 631, 5-week-RT: 629). The proportion of patients with maximum grade ≥ 2 AEs were 284 (45 %) in 3-week-RT and 326 (51.8 %) in 5-week-RT. Overall, 88 (7 %) grade 3, one grade 4 and no grade 5 AEs were observed. Reported AEs were mostly dermatitis, fatigue, and pain, numerically lower in 3-week-RT than 5-week-RT. Grade ≥ 2 dermatitis was more frequent in patients receiving a tumour-bed boost or with BMI > 30 but numerically less frequent with 3-week-RT than 5-week-RT even in those subgroups. Of the 552 patients with breast-conserving surgery who completed cosmetic evaluation at M6, 88.4 % had excellent to good cosmetic results with no imbalance between groups.

CONCLUSION

Early AEs were mild and do not raise safety concerns for 3-week-RT in women receiving nodal RT.

Heart substructure exposure during left breast cancer radiotherapy: a dosimetric comparison between hybrid VMAT and 3DCRT in free breathing and deep inspiration breath hold (DIBH)

BACKGROUND AND PURPOSE

Radiotherapy plays a pivotal role in breast cancer treatment. Incidental irradiation of the heart can cause cardiac toxicity. We conducted a dosimetric comparison between Hybrid VMAT (H-VMAT) and 3D Conformal Radiotherapy (3DCRT) in both Free Breathing (FB) and Deep inspiration breath hold (DIBH) techniques for left-sided breast cancer patients.

MATERIALS AND METHODS

Thirty-seven patients underwent CT scans in both FB and DIBH positions. Heart substructures were delineated following established guidelines. Subsequently, 3DCRT and H-VMAT plans were generated for each patient in both breath techniques. The dosimetric parameters of heart and its cavities were analysed: Dmean(Gy) and V5Gy(%) for heart substructures, Dmean(Gy), V25Gy(%) and V30Gy(cm3) for heart and D98%(%), D2%(%), D50%(%) and V95%(%) or V90%(%) for PTVs. Statistical analyses were performed.

RESULTS

The analysis revealed statistically significant differences for the heart, and its cavities. The 3DCRT plans generated in DIBH offered a statistically significant lower dose for the heart and its substructures compared to the other techniques. When comparing PTV dosimetry, the H-VMAT plans showed an increase D98%(%) and a decrease D2%(%) relative to the 3DCRT plans, for both breathing techniques employed.

CONCLUSION

Our study demonstrates significant differences in the dosimetric outcomes for the heart substructures among the four evaluated techniques, with 3DCRT in DIBH yielding the lowest parameters for most substructures. Although H-VMAT provided superior target coverage, it resulted in greater low doses incidental exposure of the heart substructures. Notably, 3DCRT plans in the DIBH setting exhibited lower doses compared to H-VMAT in FB, supporting its preferential use for minimising cardiac exposure.

ESMO-ESTRO framework for assessing the interactions and safety of combining radiotherapy with targeted cancer therapies or immunotherapy

With the emergence of targeted therapies and immunotherapy, various cellular pathways are utilized to improve tumor control and patient survival. In patients receiving these new agents, radiotherapy is commonly applied with both radical and palliative intent. Combining radiotherapy with targeted therapies or immunotherapy may improve treatment outcomes, but may also lead to increased toxicity. High-quality toxicity data and evidence-based guidelines regarding combined therapy are very limited. The present framework, developed by ESMO and ESTRO, explores the main biological effects and interaction mechanisms of radiotherapy combined with targeted agents or immunotherapy. It addresses general clinical factors to take into consideration when deciding on whether and/or how to combine radiotherapy with these agents. Furthermore, it provides pragmatic, biological mechanism-based, clinical considerations for combining radiotherapy with various targeted agents or immunotherapy.

Identification of gene signatures associated with lactation for predicting prognosis and treatment response in breast cancer patients through machine learning

As a newly discovered histone modification, abnormal lactation has been found to be present in and contribute to the development of various cancers. The aim of this study was to investigate the potential role between lactylation and the prognosis of breast cancer patients. Lactylation-associated subtypes were obtained by unsupervised consensus clustering analysis. Lactylation-related gene signature (LRS) was constructed by 15 machine learning algorithms, and the relationship between LRS and tumor microenvironment (TME) as well as drug sensitivity was analyzed. In addition, the expression of genes in the LRS in different cells was explored by single-cell analysis and spatial transcriptome. The expression levels of genes in LRS in clinical tissues were verified by RT-PCR. Finally, the potential small-molecule compounds were analyzed by CMap, and the molecular docking model of proteins and small-molecule compounds was constructed. LRS was composed of 6 key genes (SHCBP1, SIM2, VGF, GABRQ, SUSD3, and CLIC6). BC patients in the high LRS group had a poorer prognosis and had a TME that promoted tumor progression. Single-cell analysis and spatial transcriptome revealed differential expression of the key genes in different cells. The results of PCR showed that SHCBP1, SIM2, VGF, GABRQ, and SUSD3 were up-regulated in the cancer tissues, whereas CLIC6 was down-regulated in the cancer tissues. Arachidonyltrifluoromethane, AH-6809, W-13, and clofibrate can be used as potential target drugs for SHCBP1, VGF, GABRQ, and SUSD3, respectively. The gene signature we constructed can well predict the prognosis as well as the treatment response of BC patients. In addition, our predicted small-molecule complexes provide an important reference for personalized treatment of breast cancer patients.

Experimental Investigation of Hematological Toxicity After Radiation Therapy Combined With Immune Checkpoint Inhibitors

PURPOSE

Combining immune checkpoint inhibitors (ICIs) with radiation therapy (RT) has led to significant advancements in cancer treatment. However, evidence from clinical and experimental studies suggests that this combination may increase hematopoietic and lymphatic toxicity. This study aims to investigate the effects of the concurrent application of ICIs (anti-PD-1 and anti-CTLA-4) on radiation-induced hematopoietic and lymphatic injuries under standardized and controlled experimental conditions.

METHODS AND MATERIALS

We used various experimental models in C57BL/6 and BALB/c mice to evaluate the impact of ICIs combined with RT on the hematopoietic system. These models involved different RT doses, regimens, and target sites in both healthy and tumor-bearing mice.

RESULTS

Our findings showed that the concurrent use of ICIs did not meaningfully affect post-RT pancytopenia kinetics or the regeneration of specific blood cell lineages over time. Consistently, combining RT with ICIs did not significantly enhance DNA damage in immune cells within the bloodstream. This outcome was comparable across different RT doses, regimens, and target sites and was reproducible in both tumor-bearing and nontumor-bearing mice. Additionally, there were no significant increases in late side effects, including reductions in bone marrow cell counts or megakaryocyte numbers, after combined radioimmunotherapy.

CONCLUSIONS

These findings suggest that combining ICIs with RT does not exacerbate hematological toxicity. This information is valuable for interpreting adverse events in clinical trials involving radioimmunotherapy and for predicting potential hematological side effects in cancer patients receiving these treatments.

Safety and efficacy of combined trastuzumab-deruxtecan and concurrent radiation therapy in breast cancer. The TENDANCE multicentric French study

PURPOSE

Trastuzumab Deruxtecan (T DXD), a new antibody drug conjugate is a new treatment option for 2nd line metastatic breast cancer (MBC) for HER2 + or HER2 low tumors. Palliative or ablative radiotherapy (RT) may be required in patients who are being treated with T-DXd. However there is a lack of evidence regarding the safety profile of combining T-DXd with RT. TENDANCE study aimed to evaluate safety and efficacy of combined T-DXd and RT.

MATERIALS AND METHODS

This retrospective multicenter study included 54 patients treated concurrently with T-DXd and RT for HER2+ and HER2 low MBC between February 2021 and December 2023. All data were collected from a web-questionnaire, centralized after medical records and validation of the protocol by the local ethical committee. Primary endpoint was the safety of combined therapy.

RESULTS

Median age was 60 years. Patients who received T-DXD were further categorized into HER2+ (40.7 %), HER2 low/hormonal receptors HR+ (40.8 %) or HER2 low/HR- (18.5 %). In the HER2+ patients, T-DXd was administered as 2nd (18.2 %) or 3rd (31.8 %) or 4th (50 %) line therapy. RT was delivered using palliative (72.2 %) or ablative doses (27.8 %). Indications consisted mostly of palliative bone irradiation (46.3 %) and stereotactic radiosurgery (SRS) (25.9 %). With the median follow-up of 9 months, 22.2 % of patients had a complete response and 77.8 % had either a partial response or stable disease. Grade 1 or 2 asthenia was observed in 51.8 % of patients, while only 16.6 % experienced other grade 1 or 2 adverse effects. There was no T-DXd therapy discontinuation related to RT.

CONCLUSION

To our knowledge, TENDANCE is the largest study evaluating concurrent T-DXd and RT. This preliminary report suggests the feasibility of the combination of RT and T-DXd with manageable toxicity rate. Longer follow-up and further prospective studies are required to confirm these results.

Endogenous Protein-Modified Gold Nanorods as Immune-Inert Biomodulators for Tumor-Specific Imaging and Therapy

Engineered modifications of nanomaterials inspired by nature hold great promise for disease-specific imaging and therapies. However, conventional polyethylene glycol modification is limited by immune system rejection. The manipulation of gold nanorods (Au NRs) modified by endogenous proteins (eP@Au) is reported as an engineered biomodulator for enhanced breast tumor therapy. The results show that eP@Au NRs neither activate inflammatory factors in vitro nor elicit rejection of immune responses in vivo. Tumor-specific eP@Au NRs exhibit a dual-modal imaging capability and trigger a mild photothermal effect under near-infrared light irradiation, enabling highly efficient imaging and therapy of tumors. Transcriptome sequencing and confirmatory experiments reveal that the antitumor effect is mainly attributed to the repression of PI3K-Akt/MAPK signaling pathways at the molecular level. This powerful and surprising in situ eP-regulated biomodulation demonstrates the advantages of convenient fabrication, inert immunogenicity, and biocompatibility, providing an alternative strategy for biomedical imaging and therapy.

Palliative radiation therapy for locally advanced breast cancer

PURPOSE OF REVIEW

Globally, breast cancer is the most commonly diagnosed cancer in women. Locally advanced breast cancers (LABCs) may necessitate palliative radiation therapy (RT) due to the severity of the patients' symptoms, inoperability, or other reasons precluding curative-intent treatment such as poor performance status and patient comorbidities. This review aims to discuss current evidence on palliative RT in LABC.

RECENT FINDINGS

Advanced targeted RT techniques have led to improvements in local control with reduced treatment-related toxicities. Emerging short-course palliative RT prescriptions offer feasible options that avoid delay in systemic therapy. Additionally, recent studies also highlight approaches for integrating palliative RT with systemic therapies.

SUMMARY

Palliative RT plays a vital role in managing symptoms and enhancing quality of life for LABC patients. However, there is currently no consensus on the optimal prescriptions for palliative RT in these patients. Standardized reporting of palliative RT studies is needed for robust comparison of efficacy and toxicity between various treatment regimens. Furthermore, future research on the optimal integration of RT with novel systemic agents is needed.

Navigating through recent evidence on locoregional breast cancer radiotherapy: an initiative by the scientific association of Swiss radiation oncology

PURPOSE

Breast cancer (BC) is the most prevalent cancer in women and radiotherapy (RT) is an integral part of its treatment. High-level evidence guides clinical decisions, but given the abundance of guidelines, a need to navigate within the evidence has been identified by the board of the Scientific Association of Swiss Radiation Oncology (SASRO). A pilot project was initiated aiming to create an overview of recent clinically relevant evidence for BC RT, to make it easily available to (radiation) oncologists and radiation oncologists in training.

METHODS

A panel of 10 radiation oncology experts for BC RT, one expert in BC surgery, and one expert in BC medical oncology critically reviewed the relevant literature. The panel comprehensively represented different geographical regions of Switzerland as well as university, cantonal, and private institutions. We sought to create a consensual overview of the most relevant questions in BC RT today, accompanied by the most recent and relevant available evidence.

RESULTS

From January 2023 to January 2024, the panel met four times to review and work on an initial draft. The final draft was reviewed and accepted by all panelists. We hereby publish this work to make it available to international audiences. After publication, the work will be made available to all SASRO members on the SASRO website. This work is to be updated every 2 years.

CONCLUSION

The identified need was addressed with a successful pilot project and will be further expanded upon in other tumor pathologies.

The integration of radiotherapy with systemic therapy in advanced triple-negative breast cancer

Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer, with high aggressiveness and poor prognosis. For patients who have undergone multiple treatments, systemic drug therapy often presents challenges with limited efficacy and significant side effects. Radiotherapy, a pivotal local treatment, has shown substantial local control benefits in patients with inoperable locally advanced or metastatic disease. Clinical evidence suggests that integrating systemic therapy with locoregional radiotherapy can confer survival advantages in advanced malignancies. Within multidisciplinary treatment, the synergy between radiotherapy and systemic therapies shows promise for enhancing outcomes and extending survival. This review synthesizes recent advances in combining radiotherapy and systemic therapy in managing advanced TNBC, focusing on preclinical and clinical evidence regarding efficacy and safety. By reviewing these advancements, we aim to identify novel therapeutic strategies and integrate clinical evidence to inform best practices in TNBC management, ultimately improving patient outcomes.

Prognostic nomograms for young breast cancer: A retrospective study based on the SEER and METABRIC databases

Background

Young breast cancer (YBC) is a subset of breast cancer that is often more aggressive, but less is known about its prognosis. In this study, we aimed to generate nomograms to predict the overall survival (OS) and breast cancer-specific survival (BCSS) of YBC patients.

Methods

Data of women diagnosed with YBC between 2010 and 2020 were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. The patients were randomly allocated into a training cohort (n = 15,227) and internal validation cohort (n = 6,526) at a 7:3 ratio. With the Cox regression models, significant prognostic factors were identified and used to construct 3-, 5-, and 10-year nomograms of OS and BCSS. Data from the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) database were used as an external validation cohort (n = 90).

Results

We constructed nomograms incorporating 10 prognostic factors for OS and BCSS. These nomograms demonstrated strong predictive accuracy for OS and BCSS in the training cohort, with C-indexes of 0.806 and 0.813, respectively. The calibration curves verified that the nomograms have good prediction accuracy. Decision curve analysis demonstrated their practical clinical value for predicting YBC patient survival rates. Additionally, we provided dynamic nomograms to improve the operability of the results. The risk stratification ability assessment also showed that the OS and BCSS rates of the low-risk group were significantly better than those of the high-risk group.

Conclusions

Here, we generated and validated more comprehensive and accurate OS and BCSS nomograms than models previously developed for YBC. These nomograms can help clinicians evaluate patient prognosis and make clinical decisions.

Associations between breast radiation dermatitis and post-mastectomy pain syndrome in patients with breast cancer: A multicenter retrospective study

Objective

This study explores the relationship between breast radiation dermatitis (BRD) and post-mastectomy pain syndrome (PMPS) among patients with breast cancer. Both BRD and PMPS significantly impact quality of life, yet their correlation and risk factors require further investigation.

Methods

We conducted a multicenter retrospective analysis of 784 patients with breast cancer who underwent postoperative radiotherapy between 2017 and 2023. Clinical data on BRD and PMPS were collected through patient questionnaires and hospital records, examining risk factors and evaluating the prevalence of PMPS among those with BRD.

Results

BRD affected 81.25% of patients, with higher incidence among older and obese individuals. PMPS was observed in 23.4% of the BRD group versus 13.6% in non-BRD patients (P=0.009). Early BRD onset during radiotherapy (P=0.004) and larger dermatitis areas (P=0.000) were strongly associated with increased PMPS risk.

Conclusions

This study highlights the significant relationship between BRD and PMPS, underscoring the need for early interventions to manage BRD and reduce chronic pain risk. Tailored care strategies could improve outcomes for high-risk patients.

The effect of sleep quality on attitudes toward death in breast cancer survivors

PURPOSE

The aim of this study was to determine the levels of sleep quality and attitudes toward death among breast cancer survivors and to examine the impact of sleep quality on attitudes toward death.

METHODS

This descriptive and correlational study was conducted with 117 patients who had been treated for breast cancer in radiation oncology. Data were collected using a Demographic Information Form, the Pittsburgh Sleep Quality Index, and the Death Attitude Profile-Revised Scale.

RESULTS

The mean score for sleep quality among breast cancer survivors was 15.17 ± 3.96, while the mean score for the Death Attitude Profile-Revised was 137.65 ± 30.74. Sleep quality was associated with marital status, place of residence, perception of economic status, presence of social support, time since diagnosis, body mass index, and other factors (p < 0.05). Attitudes toward death were associated with age, educational level, occupation, place of residence, perception of economic status, comorbidity, histopathological stage, chemotherapy status, type of breast surgery, and other factors (p < 0.05). Additionally, a moderately positive correlation was found between sleep quality and attitudes toward death among women undergoing breast cancer treatment (r = 0.368, p < 0.001). It was determined that patients' sleep quality, education status, and comorbidity had a significant effect on attitudes toward death and the variables explained 29.4% of the variance (R2 = 0.294) (p < 0.001).

CONCLUSION

This study shows that there is a significant relationship between sleep quality and attitudes toward death in cancer patients and that sleep quality affects attitudes toward death. In addition, when evaluating the sleep quality and attitudes toward death of women treated for breast cancer, taking into account their sociodemographic characteristics and treatment characteristics may contribute positively to the recovery process and quality of life.

Escalation and De-Escalation of Adjuvant Radiotherapy in Early Breast Cancer: Strategies for Risk-Adapted Optimization

Postoperative radiotherapy (RT) is recommended after breast-conserving surgery and mastectomy (with risk factors). Consideration of pros and cons, including potential side effects, demands the optimization of adjuvant RT and a risk-adapted approach. There is clear de-escalation in fractionation-hypofractionation should be considered standard. For selected low-risk situations, PBI only or even the omission of RT might be appropriate. In contrast, tendencies toward escalating RT are obvious. Preoperative RT seems attractive for patients in whom breast reconstruction is planned or for defining the tumor location more precisely with the potential of giving ablative doses. Dose escalation by a (simultaneous integrated) boost or the combination with new compounds/systemic treatments may increase antitumor efficacy but also toxicity. Despite low evidence, RT for oligometastatic disease is becoming increasingly popular. The omission of axillary dissection in node-positive disease led to an escalation of regional RT. Studies are ongoing to test if any axillary treatment can be omitted and which oligometastatic patients do really benefit from RT. Besides technical improvements, the incorporation of molecular risk profiles and also the response to neoadjuvant systemic therapy have the potential to optimize the decision-making concerning if and how local and/or regional RT should be administered.

6th and 7th International consensus guidelines for the management of advanced breast cancer (ABC guidelines 6 and 7)

This manuscript describes the Advanced Breast Cancer (ABC) international consensus guidelines updated at the last two ABC international consensus conferences (ABC 6 in 2021, virtual, and ABC 7 in 2023, in Lisbon, Portugal), organized by the ABC Global Alliance. It provides the main recommendations on how to best manage patients with advanced breast cancer (inoperable locally advanced or metastatic), of all breast cancer subtypes, as well as palliative and supportive care. These guidelines are based on available evidence or on expert opinion when a higher level of evidence is lacking. Each guideline is accompanied by the level of evidence (LoE), grade of recommendation (GoR) and percentage of consensus reached at the consensus conferences. Updated diagnostic and treatment algorithms are also provided. The guidelines represent the best management options for patients living with ABC globally, assuming accessibility to all available therapies. Their adaptation (i.e. resource-stratified guidelines) is often needed in settings where access to care is limited.

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.

Revolutionizing cancer treatment: Harnessing the power of terrestrial microbial polysaccharides

Cancer treatment faces numerous challenges, such as inadequate drug targeting, steep price tags, grave toxic side effects, and limited therapeutic efficacy. Therefore, there is an urgent need for a safe and effective new drug to combat cancer. Microbial polysaccharides, complex and diverse biological macromolecules, exhibit significant microbial variability and uniqueness. Studies have shown that terrestrial microbial polysaccharides possess a wide range of biological activities, including immune enhancement, antioxidant properties, antiviral effects, anti-tumour potential, and hypoglycemic functions. To delve deeper into the structure-activity relationship of these land-based microbial polysaccharides against cancer, we conducted a comprehensive review and analysis of anti-cancer literature published between 2020 and 2024. The anticancer efficacy of terrestrial microbial polysaccharides is influenced by multiple factors, including the microbial species, existing form, chemical structure, and polysaccharide purity. According to the literature, an optimal molecular weight and good water solubility are essential for demonstrating anticancer activity. Furthermore, the addition of mannose and galactose has been found to significantly enhance the anticancer properties of these polysaccharides. These insights will serve as a valuable reference for future research and progress in the field of cancer drug therapy, particularly with regards to terrestrial microbial polysaccharides.

Locoregional Radiotherapy in Patients with Advanced Breast Cancer Treated with Cyclin-Dependent Kinase 4/6 Inhibitors Based on Real-World Data

BACKGROUND

The use of locoregional radiotherapy (RT) in patients with advanced ER-positive, HER2-negative breast cancer remains a topic of ongoing debate. In this study, we aimed to evaluate the efficacy of locoregional RT in advanced breast cancer patients treated with cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) in a first-line setting.

METHODS

We conducted a retrospective analysis of patients diagnosed with advanced breast cancer between 2018 and 2023 who received treatment with CDK4/6i and underwent locoregional radiotherapy.

RESULTS

Among the 371 patients treated with CDK4/6i as part of their first-line therapy, 23 received locoregional RT either concurrently or sequentially with CDK4/6 inhibitors. Disease progression within the breast occurred in 19 patients (5.1%). Among these cases, five patients had previously undergone breast RT (5/23, 21.7%), while 14 did not (14/348, 4.0%, p = 0.004). All cases of local progression after RT followed palliative doses and were accompanied by early systemic progression. The 2-year PFS in the entire cohort of patients treated with locoregional RT was 65.7% (95% CI: 40.5-82.3%). Notably, patients who received higher RT doses had longer 2-year PFS (83.3%, 95% CI: 27.3-97.5%) than those with palliative RT doses (59.3%, 95% CI: 30.7-79.3%); however, the results were not statistically significant (p = 0.58). Furthermore, the 2-year local control in the entire cohort with locoregional RT was 73.0% (95% CI: 46.5-87.9%). Importantly, no local progression was observed after RT when using high doses.

CONCLUSIONS

The addition of locoregional radiotherapy to first-line CDK4/6 inhibitors warrants further investigation across various clinical scenarios in advanced breast cancer. Palliative radiation regimens delivered early in breast oligoprogression may not always suffice, emphasizing the need for comprehensive studies in this context.

Impact of concurrent antibody-drug conjugates and radiotherapy on symptomatic radiation necrosis in breast cancer patients with brain metastases: a multicenter retrospective study

AIM

We aimed to investigate the impact of concurrent antibody-drug conjugates (ADC) and radiotherapy on symptomatic radiation necrosis (SRN) in breast cancer patients with brain metastases (BM).

METHODS

This multicenter retrospective study uses four institutional data. Eligibility criteria were histologically proven breast cancer, diagnosed BM with gadolinium-enhanced MRI, a Karnofsky performance status of 60 or higher, and radiotherapy for all BM lesions between 2017 and 2022. Patients with leptomeningeal dissemination were excluded. Concurrent ADC was defined as using ADC within four weeks before or after radiotherapy. The cumulative incidence of SRN until December 2023 with death as a competing event was compared between the groups with and without concurrent ADC. Multivariable analysis was performed using the Fine-Gray model.

RESULTS

Among the 168 patients enrolled, 48 (29%) received ADC, and 19 (11%) had concurrent ADC. Of all, 36% were HER2-positive, 62% had symptomatic BM, and 33% had previous BM radiation histories. In a median follow-up of 31 months, 18 SRNs (11%) were registered (11 in grade 2 and 7 in grade 3). The groups with and without concurrent ADC had 5 SRNs in 19 patients and 13 SRNs in 149, and the two-year cumulative incidence of SRN was 27% vs. 7% (P = 0.014). Concurrent ADC was associated with a higher risk of SRN on multivariable analysis (subdistribution hazard ratio, 3.0 [95% confidence interval: 1.1-8.3], P = 0.030).

CONCLUSIONS

This study suggests that concurrent ADC and radiotherapy are associated with a higher risk of SRN in HER2-positive breast cancer patients.

Bridging Discoveries and Treatments: The New Landscape of Breast Cancer Research

Welcome to our Special Issue, "Advances in Breast Cancer Research and Treatment" of Life, where we have embarked on a comprehensive exploration of groundbreaking studies that advance our understanding and management of breast cancer [...].

The Safety and Efficacy of the Combination of Sacituzumab Govitecan and Palliative Radiotherapy-A Retrospective Multi-Center Cohort Study

Sacituzumab govitecan (SG) is a new treatment option for patients with metastatic triple-negative and hormone receptor-positive, HER2-negative breast cancer. This antibody-drug conjugate is currently approved as monotherapy. Palliative radiotherapy is frequently used to treat symptomatic metastases locally. Concurrent use of SG and irradiation was excluded in clinical trials of SG, and there are currently limited published data. We report here a systematic review, as well as a retrospective multi-center study of 17 patients with triple-negative breast cancer who received concurrent SG and radiotherapy. In these patients, concurrent use was found to be efficient, safe and well tolerated. There were no apparent differences in moderate or severe acute toxicity according to the timing of SG administration.