Background: This study aimed to develop and externally validate ultrasound radiomics models for preoperative prediction of high axillary nodal burden in nodepositive breast cancer and to compare the value of intratumoral and peritumoral features. Methods: This retrospective dualcenter study included 404 patients with pathologically confirmed breast cancer and axillary lymph node metastasis, including 294 patients in the training cohort and 110 in the external validation cohort. Axillary nodal burden was categorized as low burden (1-2 metastatic lymph nodes) or high burden (>= 3 metastatic lymph nodes) according to postoperative pathology. Intratumoral and 3mm peritumoral ultrasound radiomics features were extracted. To avoid information leakage, the training and validation cohorts were separated before preprocessing and model development. Six prespecified models were developed in the training cohort and independently evaluated in the external validation cohort. Results: Cortical thickening, hilum status, and ultrasoundreported axillary lymph node status were independent clinical predictors of high nodal burden. In external validation, all models showed limited discrimination, with areas under the receiver operating characteristic curve (AUCs) ranging from 0.585 to 0.621. The intratumoral radiomics model achieved the numerically highest validation AUC of 0.621, with a sensitivity of 0.762 and specificity of 0.382, followed by the combined models (AUC = 0.613), clinical model (AUC = 0.597), and peritumoral model (AUC = 0.585). Bootstrap comparisons showed no significant differences between models. Calibration performance was suboptimal in the external validation cohort. Conclusions: Under a leakagefree external validation framework, ultrasound radiomics showed limited but exploratory value for predicting high axillary nodal burden in nodepositive breast cancer. The current models should not be used as standalone tools for axillary management.
Background: Breast Imaging Reporting and Data System (BI-RADS) 4a breast lesions are considered low suspicion for malignancy (2-10%), yet current guidelines recommend biopsy for definitive diagnosis, leading to a high rate of unnecessary invasive procedures. Contrast-enhanced ultrasound (CEUS) provides real-time microvascular perfusion information that may improve risk stratification in this indeterminate category. This study aimed to evaluate the diagnostic performance of CEUS in differentiating benign from malignant BI-RADS 4a lesions, with a focus on its potential to reduce avoidable biopsies. Methods: In this prospective diagnostic study, consecutive patients with BI-RADS 4a lesions identified on conventional ultrasound underwent CEUS examination using a sulfur-hexafluoride microbubble contrast agent. CEUS cine loops were independently reviewed by two blinded readers. Lesions were classified as CEUS-positive (suspicious for malignancy) if they exhibited >= 2 predefined malignant perfusion features (e.g., heterogeneous hyper-enhancement, centripetal filling, perfusion defects, fast wash-in/wash-out). Histopathology from biopsy or surgery served as the reference standard. Diagnostic accuracy metrics-sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), accuracy, and area under the receiver-operating-characteristic curve (AUC)-were calculated. Results: A total of 149 BI-RADS 4a lesions were included. Histopathology revealed 129 benign and 20 malignant/high-risk lesions. CEUS demonstrated a sensitivity of 85.0% (95% confidence interval [CI] 62.1-96.8%), specificity of 89.9% (95% CI 83.3-94.6%), PPV of 47.2% (32.9%-62.0%), and NPV of 98.2% (95% CI 93.8-99.6%). The overall accuracy was 89.3% (95% CI 83.2-93.7%), with an AUC of 0.88 (95% CI 0.81-0.94). Malignant lesions showed significantly higher frequencies of heterogeneous hyper-enhancement, centripetal perfusion, perfusion defects, and fast wash-in/wash-out kinetics (all p < 0.001). Inter-observer agreement for CEUS classification was substantial (kappa=0.76). Conclusion: CEUS exhibits high diagnostic performance, especially a high NPV, in the evaluation of BI-RADS 4a breast lesions. It can reliably identify a subset of lesions with a very low probability of malignancy, suggesting that CEUS may help identify a subset of patients in whom immediate biopsy could be considered for deferral within a shared decision-making framework, though prospective validation in larger cohorts is needed. These findings support the integration of CEUS as a valuable adjunctive triage tool to reduce unnecessary biopsies in low-suspicion breast lesions.
Background: Thyroid-stimulating hormone (TSH) suppression therapy remains an important treatment option for patients with low-risk differentiated thyroid cancer. This study aimed to analyze the potential influencing factors affecting TSH suppression outcomes in patients with postoperative low-risk papillary thyroid cancer (PTC). Methods: A total of 223 low-risk PTC patients were enrolled in this single-center cross-sectional study between September 2024 and February 2025. Based on the TSH level measured at 4-6 months post-lobectomy, the patients were divided into three groups: an excessive TSH suppression group (TSH < 0.5 mU/L), optimal TSH suppression group (TSH 0.5-2.0 mU/L), and insufficient TSH suppression group (TSH > 2.0 mU/ L). The clinicopathological data of the patients, including demographic, clinical laboratory, pathological, and lifestyle characteristics, were analyzed to investigate the factors influencing TSH suppression therapy. Results: There were no statistically significant differences in age, marital status, preoperative freetriiodothyronine (FT3), freethyroxine (FT4), thyroglobulin antibody (TG-Ab), thyroid peroxidase antibody (TPO-Ab), thyroglobulin (Tg) level, longest tumor diameter, lesion site, central lymph node metastasis, Hashimoto's thyroiditis, BRAF V600E mutation, levothyroxine intake habits, dietary habits, or sleep habits among the three groups (all P > 0.05). The distributions of sex, body mass index (BMI), comorbidities, preoperative TSH levels, multifocal lesions, levothyroxine dose, physical activity, and sedentary time differed significantly among the three groups (all P < 0.05). Multivariate logistic regression analyses demonstrated that excessive TSH suppression was significantly associated with female sex, a higher levothyroxine dose (>= 1.6 & micro;g/kg/day), lower preoperative TSH levels, lower physical activity, and higher sedentary time. Conversely, insufficient TSH suppression was independently associated with higher BMI and lower levothyroxine dose ( < 1.6 & micro;g/kg/day). Conclusions: A complex interplay exists among demographic, clinical, and lifestyle factors in postoperative TSH management. Prospective studies with objective lifestyle measurements are needed to confirm these associations before clinical implementation.
