External validation of a prognostic model based on total tumor load of sentinel lymph node for early breast cancer patients

Background: A prognostic model based on the results of molecular analysis of sentinel lymph nodes (SLN) is needed to replace the information that staging the entire axilla provided. The aim of the study is to conduct an external validation of a previously developed model for the prediction of 5-year DFS in a group of breast cancer patients that had undergone SLN biopsy assessed by the One Step Nucleic Acid Amplification (OSNA) method. Methods: We collected retrospective data of 889 patients with breast cancer, who had not received systemic treatment before surgery, and who underwent SLN biopsy and evaluation of all SLN by OSNA. The discrimination ability of the model was assessed by the area under the ROC curve (AUC ROC), and its calibration by comparing 5-years DFS Kaplan–Meier estimates in quartile groups of model predicted probabilities (MPP). Results: The AUC ROC ranged from 0.78 (at 2 years) to 0.73 (at 5 years) in the training set, and from 0.78 to 0.71, respectively, in the validation set. The MPP allowed to distinguish four groups of patients with heterogeneous DFS (log-rank test p < 0.0001). In the highest risk group, the HR were 6.04 [95% CI 2.70, 13.48] in the training set and 4.79 [2.310, 9.93] in the validation set. Conclusions: The model for the prediction of 5-year DFS was successfully validated using the most stringent form of validation, in centers different from those involved in the development of the model. The external validation of the model confirms its utility for the prediction of 5-year DFS and the usefulness of the TTL value as a prognostic variable.This study was supported by Sysmex España S.L

Prognostic and Predictive Effects of Tumor and Plasma miR-200c-3p in Locally Advanced and Metastatic Breast Cancer

While the role of miR-200c in cancer progression has been established, its expression and prognostic role in breast cancer is not completely understood. The predictive role of miR-200c in response to chemotherapy has also been suggested by some studies, but only limited clinical evidence is available. The purpose of this study was to investigate miR-200c-3p in the plasma and primary tumor of BC patients. The study design included two cohorts involving women with locally advanced (LABC) and metastatic breast cancer. Tumor and plasma samples were obtained before and after treatment. We found that miR-200c-3p was significantly higher in the plasma of BC patients compared with the controls. No correlation of age with plasma miR-200c-3p was found for controls or for BC patients. MiR-200c-3p tumor expression was also associated with poor overall survival in LABC patients treated with neoadjuvant chemotherapy, independently of pathological complete response or clinical stage. Our findings suggest that plasmatic miR-200c-3p levels could be useful for BC staging, while the tumor expression of miR-200c-3p might provide further prognostic information beyond residual disease in BC treated with neoadjuvant chemotherapy