Lee J, et al. J Breast Cancer. 2025 Jun;28:e24. https://doi.org/10.4048/jbc.2024.0303

Background: Artificial intelligence-based computer-aided diagnosis (AI-CAD) systems are increasingly used in breast ultrasonography; however, their diagnostic performance may vary with breast density. Given that dense breasts are highly prevalent among Asian women, understanding this relationship is essential for optimizing AI-assisted imaging strategies. Therefore, this study aims to evaluate the effect of breast density on the diagnostic accuracy of an AI-CAD ultrasound system in BI-RADS category 4 (C4) breast lesions. Methods: Overall, 110 consecutive BI-RADS C4 lesions were reviewed between January and December 2023. An AI-CAD ultrasound system automatically assigned BI-RADS categories and calculated the probability of malignancy (POM) using static ultrasound images. Histopathology served as the reference standard, with atypia and malignancy combined into a non-benign category. Diagnostic performance—including sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and overall accuracy—was analyzed based on breast density (BI-RADS B–D), determined using AI-assisted mammography. Results: Overall, the sensitivity and NPV were 81.3% and 87.5%, respectively, while the specificity and PPV were lower at 53.8% and 41.9%. All diagnostic performance metrics improved with increasing breast density. In the density D category, sensitivity (92.3%), specificity (61.5%), NPV (96.0%), and accuracy (69.2%) were highest. Additionally, concordance between AI-assigned BI-RADS categories and histopathologic diagnoses increased with density (B: 50.0%, C: 57.5%, D: 67.3%). Across all density groups, non-benign lesions consistently demonstrated higher POM values. Conclusions: Breast density significantly affects the diagnostic performance of AI-CAD ultrasound in BI-RADS C4 lesions. The AI system demonstrates higher accuracy and concordance in dense breasts, suggesting more consistent lesion interpretation in high-density environments. These findings highlight the potential utility of AI-assisted ultrasound as a diagnostic adjunct, particularly for Asian women, who commonly have dense breast composition. Further multicenter, real-time validation studies are warranted to validate these findings.

Background: Breast cancer requires long-term surveillance, as recurrence and mortality risks extend beyond 10 years. Mammography (MMG) is the standard imaging modality; however, its effectiveness is reduced in Asian women owing to dense breast tissue. The optimal timing of surveillance MMG after breast-conserving surgery remains unclear, particularly the value of routine 6-month MMG. We evaluated the roles of MMG and ultrasound in detecting ipsilateral and contralateral breast cancer recurrence after breast-conserving surgery. Methods: This retrospective study included 961 patients with operable breast cancer who underwent breast-conserving surgery with or without axillary surgery between 2011 and 2015 at Kyungpook National University Chilgok Hospital. Surveillance consisted of biannual imaging for the first 2 years, followed by annual imaging for up to 10 years. Ipsilateral and contralateral breast cancer recurrences were analyzed according to detection modality, including MMG and ultrasound. Multivariate Cox proportional hazards regression analysis was performed to identify independent risk factors for recurrence. Results: During a mean follow-up of 139 months, 56 patients (5.8%) experienced locoregional recurrence, and 41 (4.3%) developed distant metastasis. Among 35 in-breast recurrences, 14 (40.0%) were ipsilateral and 21 (60.0%) contralateral. Ipsilateral recurrences were more often detected via either MMG or ultrasound alone, whereas contralateral cancers were typically detected through both modalities. During the first postoperative year, all ipsilateral and contralateral recurrences were detected exclusively by ultrasound, with no cancers identified by 6-month MMG (95% CI for 6-month detection: 0–0.38%). Multivariate analysis identified positive axillary lymph node status as the only independent predictor of locoregional recurrence (HR 2.52, 95% CI 1.14–5.54, p = 0.022). Detection patterns showed no significant differences across molecular subtypes (p = 0.665). Conclusions: Annual MMG remains appropriate for breast cancer surveillance in accordance with current guidelines. However, MMG at 6 months post-surgery may be unnecessary, as early detection during the first year was achieved solely by ultrasound. The complementary role of MMG and ultrasound is consistent regardless of molecular subtype.

Background/Objectives: Considering the increasing importance placed on the quality of life among those who survive cancer, breast reconstruction is no longer limited to only compensating for breast loss; achieving the patient’s preferences is now considered. However, the optimal surgical approach (subpectoral plane vs. prepectoral plane) in single-stage direct-to-implant breast reconstruction (DTIBR) has not been established. The aim of this study was to summarize the principles for selecting between the subpectoral and prepectoral planes in DTIBR. Methods: In this retrospective study, we evaluated 543 patients with breast cancer who underwent DTIBR between March 2018 and October 2025. Postmastectomy reconstruction was performed in the subpectoral plane when the defect showed greater breast height than width, whereas the prepectoral plane was used when breast width exceeded height. Complications requiring reoperation were analyzed. Patient satisfaction was evaluated based on overall satisfaction, esthetic outcome, physical symptoms, psychosocial impact, and decision satisfaction using a visual analog scale. Results: The subpectoral dual-plane approach was most commonly used between 2018 and 2019, while the prepectoral plane became predominant after 2020. Overall, 83 (14.4%) patients developed major complications. The overall satisfaction score was 4.1 ± 0.80 in the subpectoral group and 4.35 ± 0.70 in the prepectoral group, showing a statistically significant difference (p value = 0.012). Conclusions: The subpectoral and prepectoral planes have distinct advantages and limitations. Ultimately, the reconstructive surgeon should determine the most appropriate option in DTIBR. Selecting the surgical plane based on the postmastectomy defect reduces complications while improving patient satisfaction.

Triple-negative breast cancer (TNBC) lacks effective targeted therapies, and the mechanisms by which developmental endothelial locus-1 (EDIL3/Del-1) promotes TNBC remain incompletely defined. We profiled Del-1 and AMPK subunits in TNBC cell lines by RT-PCR and immunoblotting, performed functional assays in CRISPR/Cas9 Del-1 knockout and AMPKβ-manipulated cells, and evaluated AMPKβ in early-stage TNBC tumors using tissue microarrays (TMA) (immunohistochemistry; n = 100) and AMPKβ2 mRNA quantification. Del-1 and AMPKβ were enriched in TNBC cells, most prominently in the mesenchymal stem-like subtype, whereas AMPKα levels were relatively stable. Increased Del-1 and activated AMPKβ enhanced proliferation and invasion, while Del-1 deletion reduced AMPKβ expression and suppressed tumor-promoting phenotypes. Mechanistically, Del-1 increased AMPKβ phosphorylation at serine 108, and a phospho-mimetic AMPKβ mutant further amplified oncogenic effects. In the pilot TMA study, high AMPKβ protein expression showed a trend toward poorer DFS in Kaplan–Meier analysis, while multivariate analysis identified high AMPKβ protein expression as an independent factor associated with poorer DFS in patients with early TNBC. These data support AMPKβ as a key mediator of Del-1-driven signaling and suggest AMPKβ could be a therapeutic target in aggressive TNBC subsets.

Background: Phyllodes tumors (PTs) are rare fibroepithelial breast neoplasms spanning a benign-to-malignant spectrum, and the extent of surgery and reconstruction differs markedly by histologic grade. The primary aim of this study was to derive a grade-stratified surgical and reconstructive algorithm. Methods: The charts of patients diagnosed with phyllodes tumor at Kyungpook National University Chilgok Hospital between January 2011 and February 2026 were retrospectively reviewed. Tumors were classified by World Health Organization criteria as benign, borderline, or malignant, and the treatment protocols, extent of surgery, and immediate reconstruction after mastectomy were analyzed. Results: Of 417 patients charted, 401 were confirmed to have phyllodes tumors and 334 carried a definitive histologic grade. Together, they formed the analyzed cohort: 251 benign (75.1%), 55 borderline (16.5%), and 28 malignant (8.4%). Benign tumors were managed predominantly by breast-conserving surgery (BCS). Twenty-six patients formed the surgical cohort, defined by the reconstructive requirement of the resection defect: all total mastectomies (n = 19) together with all breast-conserving resections reconstructed by the plastic surgical team (oncoplastic breast-conserving surgery, n = 7). Reconstruction was performed in 21 (80.8%) with latissimus dorsi-based flaps, local flaps, or direct-to-implant reconstruction. Adjuvant radiotherapy was confined to malignant disease (7 of 15 malignant PTs, 46.7%; p = 0.010). Over a median follow-up of 32.7 months, local recurrence developed in four patients (15.4%) and two malignant tumors were fatal. In an illustrative case of recurrent malignant PT with rib metastasis, a widely opened pleural cavity was sealed with a single sheet of non-fenestrated acellular dermal matrix (ADM), which was found to be fully incorporated and still sealing the pleura at later implant explantation. Conclusions: A grade-stratified strategy (BCS for benign tumors and mastectomy with reconstruction for borderline/malignant disease) balances oncologic safety with aesthetic outcome.