The use of longitudinal CT-based radiomics and clinicopathological features predicts the pathological complete response of metastasized axillary lymph nodes in breast cancer.

BACKGROUND: Accurate assessment of axillary status after neoadjuvant therapy for breast cancer patients with axillary lymph node metastasis is important for the selection of appropriate subsequent axillary treatment decisions. Our objectives were to accurately predict whether the breast cancer patients with axillary lymph node metastases could achieve axillary pathological complete response (pCR). METHODS: We collected imaging data to extract longitudinal CT image features before and after neoadjuvant chemotherapy (NAC), analyzed the correlation between radiomics and clinicopathological features, and developed models to predict whether patients with axillary lymph node metastasis can achieve axillary pCR after NAC. The clinical utility of the models was determined via decision curve analysis (DCA). Subgroup analyses were also performed. Then, a nomogram was developed based on the model with the best predictive efficiency and clinical utility and was validated using the calibration plots. RESULTS: A total of 549 breast cancer patients with metastasized axillary lymph nodes were enrolled in this study. 42 independent radiomics features were selected from LASSO regression to construct a logistic regression model with clinicopathological features (LR radiomics-clinical combined model). The AUC of the LR radiomics-clinical combined model prediction performance was 0.861 in the training set and 0.891 in the testing set. For the HR + /HER2 - , HER2 + , and Triple negative subtype, the LR radiomics-clinical combined model yields the best prediction AUCs of 0.756, 0.812, and 0.928 in training sets, and AUCs of 0.757, 0.777 and 0.838 in testing sets, respectively. CONCLUSIONS: The combination of radiomics features and clinicopathological characteristics can effectively predict axillary pCR status in NAC breast cancer patients.

Clinical significance of topoisomerase 2A expression and gene change in operable invasive breast cancer.

This study aims to investigate clinical significance of topoisomerase 2A (TOP2A) expression and TOP2A gene change in operable invasive breast cancer. This is a retrospective analysis, which includes 256 patients diagnosed as operable invasive breast cancer. All postoperational waxed specimens were subjected to resectioning for staining. Estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER-2), KI-67, TOP2A expression, and TOP2A gene changes were detected by immunohistochemistry (IHC) and fluorescent in situ hybridization technique (FISH), respectively. Correlation between TOP2A expression and clinicopathological characteristics was also investigated. Effects of TOP2A protein or gene changes on survival rate were detected. Results indicated that 165 were TOP2A positive (64.5 %), and 31 were gene amplification positive (12.1 %). Positive rate of TOP2A expression showed significant correlations with ER, KI-67, and HER-2. The difference of 5-year overall survival (OS) between TOP2A-positive and TOP2A-negative groups did not reach statistical significance (OS: P = 0.321, 85.9 vs. 79.6 %; disease-free survival [DFS]: P = 0.247, 83.3 vs. 75.3 %). Five-year OS in TOP2A amplification group was 68.8 %, which is lower than deficiency and control group (P > 0.05). Subgroup analysis showed no significant differences of OS and DFS either between TOP2A-positive and TOP2A-negative groups or between TOP2A amplification and control group in population of patients with HER-2 amplification, triple negative breast cancer, or hormone-positive breast cancer. In conclusion, positive rate of TOP2A expression correlates significantly with ER, KI-67, and HER-2. However, prognostic significance of either TOP2A expression or TOP2A gene changes in breast cancer and its various subtypes is limited.