RESUMEN
BACKGROUND: Metaplastic breast cancer (MBC) is a rare and heterogeneous breast cancer subtype, and there are critical gaps in our understanding of its long-term outcomes. This retrospective cohort study aimed to address these gaps by scrutinizing the pathological and clinical aspects of MBC to enhance clinical decision-making and refine patient care strategies. METHODS: This registry-based retrospective cohort study included females aged ≥21 years diagnosed with MBC or matrix-producing carcinoma. The data were obtained from January 2001-August 2020 from the XXXX Registry of XXXX, which included 23,935 patients. Demographic and clinicopathological characteristics, neoadjuvant chemotherapy responses, and survival outcomes were analyzed. Statistical assessments involved univariate and multivariate Cox proportional hazards models and Kaplan-Meier survival analyses. RESULTS: This study enrolled 170 patients; 87.1% had non-metastatic disease and 12.9% had metastatic disease. The age of patients at diagnosis ranged from 46 to 65 years (median, 56 years). The cohort's predominant characteristics were advanced clinical stage (77.6%), node negativity (67.6%), and grade 3 disease (74.1%). In patients receiving curative intent treatment, neoadjuvant chemotherapy yielded a pathological complete response of 19.2% and a disease progression rate of 46.2%. Multivariate analysis showed that adjuvant radiation therapy significantly improved overall survival (OS) and disease-free survival (DFS), with hazard ratios (HRs) of 0.29 (95% confidence interval [CI], 0.13 - 0.62; p < 0.005) and 0.23 (95% CI, 0.10-0.50; p < 0.005), respectively. Clinical T3 and T4 stages, and nodal involvement were associated with poor outcomes. Stable disease after neoadjuvant chemotherapy was associated with poor OS and DFS. CONCLUSION(S): This study sheds light on the complex landscape of MBC and emphasizes the pivotal role of adjuvant radiotherapy in enhancing patient outcomes. Despite advancements, challenges persist that warrant continued research to refine neoadjuvant chemotherapy strategies and delve into the nuanced factors that influence treatment responses.
RESUMEN
Triple-negative breast cancer (TNBC) has a poor prognosis with limited therapeutic options available for affected patients. Efforts are ongoing to identify surrogate markers for tumor-specific CD8+ T cells that can predict the response to immune checkpoint inhibitor (ICI) therapies, such as programmed cell death protein 1 or programmed cell death ligand-1 blockade. We have previously identified tumor-specific CD39+CD8+ T cells in non-small cell lung cancer that might help predict patient responses to programmed cell death protein 1 or programmed cell death ligand-1 blockade. Based on this finding, we conducted a comparative interrogation of TNBC in an Asian cohort to evaluate the potential of CD39 as a surrogate marker of tumor-specific CD8+ T cells. Using ICI-treated TNBC mouse models (n = 24), flow cytometric analyses of peripheral blood mononuclear cells and tumor-infiltrating lymphocytes revealed that >99% of tumor-specific CD8+ T cells also expressed CD39. To investigate the relationship between CD39+CD8+ T-cell density and CD39 expression with disease prognosis, we performed multiplex immunohistochemistry staining on treatment-naive human TNBC tissues (n = 315). We saw that the proportion of CD39+CD8+ T cells in human TNBC tumors correlated with improved overall survival, as did the densities of other CD39+ immune cell infiltrates, such as CD39+CD68+ macrophages. Finally, increased CD39 expression on CD8+ T cells was also found to predict the response to ICI therapy (pembrolizumab) in a separate cohort of 11 TNBC patients. These findings support the potential of CD39+CD8+ T-cell density as a prognostic factor in Asian TNBC patients.
