Triple‐negative breast cancer (TNBC) is the most aggressive breast cancer subtype, and is characterized by an early metastatic tendency, marked biological heterogeneity, and poor clinical outcomes. Among all distant metastatic sites, the brain represents one of the most devastating locations, as brain metastasis is associated with substantial neurological morbidity, limited therapeutic options, and short survival. TNBC displays a disproportionate propensity for brain metastasis compared with hormone receptor‐positive disease, yet effective systemic treatment remains challenging because of the blood–brain barrier (BBB), the distinct brain tumor microenvironment (TME), and the absence of broadly applicable molecular targets. In this review, we summarize the molecular basis of TNBC brain metastasis with an emphasis on four major aspects: tumor microenvironmental remodeling, BBB interaction, oncogenic signaling pathways, and metabolic reprogramming. We discuss how reactive astrocytes, microglia, inflammatory cytokines, and tumor‐intrinsic programs collectively facilitate brain colonization and therapeutic resistance. In addition, we review current and emerging treatment strategies, including chemotherapy, antibody–drug conjugates, targeted therapy, immunotherapy, and novel drug‐delivery systems. Particular attention is given to the translational gap between preclinical promise and clinical benefit, the frequent exclusion of patients with active brain metastases from clinical trials, and the need for more rigorous intracranial efficacy assessment. A better understanding of the dynamic interaction between TNBC cells and the brain niche may support the development of more effective and biologically informed therapeutic strategies for this high‐risk population.
Objective To evaluate whether targeted ultrasound (TUS) combined with contrast‐enhanced ultrasound (CEUS) can safely reclassify MRI‐detected BI‐RADS 4 nonmass enhancement (NME) lesions to reduce unnecessary biopsies while maintaining high diagnostic sensitivity for breast cancer. Materials and Methods In this prospective study (2017–2023), we enrolled 169 MRI‐detected BI‐RADS 4 NME lesions in 167 women (23–84 years). All patients underwent TUS and CEUS within one week after MRI, followed by surgical pathology. We evaluated whether TUS combined with CEUS could reclassify lesions to avoid biopsy without compromising cancer detection. Results Among 169 lesions (83 benign, 86 malignant), TUS detected 97.0%. Using predefined CEUS benign criteria, 36/83 benign lesions (43.4%) and 39/169 overall (23.1%) could have safely avoided biopsy. Diagnostic sensitivity remained high (96.5%, 83/86). CEUS significantly improved detection of DCIS, upgrading 87.5% (21/24) of MRI‐BI‐RADS 4a DCIS/DCIS with microinvasion to BI‐RADS ≥4b. False‐negative cases were limited to three lesions in challenging anatomical locations (subareolar or occult). Biopsy reduction was highest in asymptomatic patients, lesions ≤ 2 cm, homogeneous enhancement, and MRI BI‐RADS 4a. Conclusions TUS combined with CEUS can substantially reduce unnecessary biopsies for MRI‐detected BI‐RADS 4 NME while maintaining excellent sensitivity. This approach is particularly effective for MRI BI‐RADS 4a lesions and small homogeneous NME and may provide a clinically practical strategy for improving diagnostic efficiency in breast cancer care.
Objectives Breast cancer is the most diagnosed cancer among women worldwide, yet important epidemiological differences exist between premenopausal and postmenopausal disease. Updated global estimates stratified by menopausal status are limited. This study aimed to quantify the global, regional, and national burden of premenopausal and postmenopausal breast cancer in 2022 and to project future trends through 2050. Methods Breast cancer incidence and mortality data for 2022 were obtained from the International Agency for Research on Cancer GLOBOCAN database. Women aged 15–49 years were classified as premenopausal and those aged ≥ 50 years as postmenopausal. Age‐standardized incidence rates (ASIRs), age‐standardized mortality rates (ASMRs), cumulative risk, and mortality‐to‐incidence ratios (MIRs) were estimated for 185 countries. Countries were further stratified by the Human Development Index (HDI) published by the United Nations Development Programme. Temporal trends were assessed using estimated annual percentage change (EAPC), and projections to 2050 were derived using the World Health Organization Cancer Tomorrow tool. Results In 2022, an estimated 2,296,607 new breast cancer cases and 666,061 deaths occurred globally. Premenopausal women accounted for 668,417 cases (29.1%) and 141,338 deaths (21.2%), while postmenopausal women accounted for 1,628,190 cases (70.9%) and 524,723 deaths (78.8%). Global ASIRs were 32.7 and 153.9 per 100,000 for premenopausal and postmenopausal women, respectively. Incidence rates were highest in very high‐HDI countries, whereas mortality and MIR were markedly higher in low‐HDI countries. Africa showed the highest MIRs for both premenopausal (40.3%) and postmenopausal (51.8%) breast cancer. HDI was positively correlated with cumulative incidence risk but strongly inversely correlated with MIR. By 2050, global cases are projected to increase to 795,908 for premenopausal and 2,756,889 for postmenopausal breast cancer. Conclusions Substantial global disparities exist in breast cancer burden and outcomes. While high‐income countries experience higher incidence, low‐resource settings bear disproportionately higher mortality. Strengthening early detection, treatment access, and cancer control systems is essential to reduce global inequities and address the growing burden of breast cancer.
Breast cancer (BC) remains the most common malignancy among women worldwide, with incidence and mortality rates continuing to rise. Alongside tumor heterogeneity and diverse clinical outcomes, increasing attention has been directed toward the role of the intratumoral microbiome as a regulator of breast tumorigenesis. Recent evidence demonstrates that breast tissue harbors one of the most diverse microbial communities compared with other cancer types, with marked differences between normobiota and malignant tissue. Intratumoral microorganisms are potentially associated with BC progression through multiple mechanisms, including modulation of inflammation, steroid hormone metabolism, and extracellular matrix remodeling. Specific taxa, including Staphylococcus , Bacillus , Fusobacterium , and Paenibacillus , have been associated with tumor aggressiveness, molecular subtypes, and patient prognosis. Moreover, the microbiome actively shapes the tumor microenvironment by altering immune infiltration, inducing resistance to anticancer therapy, and regulating immune checkpoint signaling, including PD‐1/PD‐L1 pathways. Microbial proteases and bacterial analogs of matrix metalloproteinases further contribute to extracellular matrix degradation and stromal remodeling, enhancing metastatic potential. Despite rapid advances, the clinical utility of intratumoral microbial signatures as predictive biomarkers of BC aggressiveness remains under investigation. Comprehensive characterization of microbial profiles across clinical and molecular subgroups may offer novel diagnostic, prognostic, and therapeutic opportunities in BC management.
Objective This study aims to compare and evaluate the dosimetric characteristics of five radiotherapy techniques in left-sided breast cancer patients following breast-conserving surgery. The five radiotherapy techniques include three-dimensional conformal radiation therapy (3D-CRT), fixed-field intensity-modulated radiation therapy (ff-IMRT), volumetric modulated arc therapy (VMAT), hybrid 3D-CRT with IMRT (CRT + IMRT), and hybrid 3D-CRT with VMAT (CRT + VMAT). Patients and Methods Ten patients with left-sided breast cancer who received postlumpectomy radiotherapy at the Department of Radiation Oncology, First Hospital of Qinhuangdao, between June 1, 2020, and June 1, 2021, were randomly enrolled in this study. For each patient, five distinct treatment plans were designed using the five aforementioned techniques (3D-CRT, ff-IMRT, VMAT, CRT + IMRT, and CRT + VMAT) based on identical computed tomography (CT) imaging datasets. Dosimetric parameters for the tumor target volume, organs at risk (OARs), and normal tissues (defined as body minus planning target volume [PTV], termed B-P) were analyzed and compared using dose-volume histograms (DVHs) and isodose distributions. Results The CRT + VMAT technique demonstrated superior PTV dose coverage, conformity, and homogeneity compared to 3D-CRT, ff-IMRT, VMAT, and CRT + IMRT (p < 0.05). In contrast, the VMAT technique achieved significantly lower V-30 (%) values for bilateral lungs and ipsilateral lung than 3D-CRT, ff-IMRT, CRT + IMRT, and CRT + VMAT (p < 0.05). The CRT + IMRT technique reduced V-5 (%) values for bilateral lungs, ipsilateral lung, and heart compared to 3D-CRT, ff-IMRT, VMAT, and CRT + VMAT (p < 0.05). Finally, 3D-CRT required the fewest monitor units (MUs) and shortest treatment time among all techniques (p < 0.05). Conclusion Clinicians may tailor radiotherapy plans to individual patients based on the distinct dosimetric profiles of each technique. For patients requiring optimal PTV dose distribution, the CRT + VMAT technique is suggest. For enhanced cardiopulmonary protection (e.g., reduced lung/heart doses), ff-IMRT or CRT + IMRT may be prioritized. Additionally, 3D-CRT should be the first choice for patients needing rapid fractionated treatment due to its efficiency in minimizing MUs and treatment time.
