Clinical Usefulness of Cytokeratin 5/6 as an Immunohistochemical Marker to Predict Prognosis in Triple-negative Breast Cancer

다국어 초록 (Multilingual Abstract)

(PR) and human epidermal growth factor receptor 2. Negative staining for all three markers defines the ‘triple-negative’ phenotype. By adding markers for cytokeratin 5/6 and epidermal growth factor receptor, triple-negative breast cancers can be divided into ‘basal-like’ and ‘non-basal-like’ subgroups. The aim of this study is to asscess the usefulness of cytokeratin 5/6 as a distinguishable marker in the basal-like subgroup of triple-negative breast cancers.
Methods : We examined, by immunohistochemistry, the expression of biological markers cytokeratin 5/6 in triple-negative breast cancers. We classified triple-negative breast cancerpatients into two groups as cytokeratin 5/6-positive and cytokeratin 5/6-negative. The clinicopathological features, such as disease free survival (DFS) and overall survival (OS) for patients with cytokeratin 5/6-positive were compared with those of the cytokeratin 5/6-negative patients.
Results : In the 131 cases of operable triple-negative breast cancer, cytokeratin 5/6-positive group was detected in 15 (11.5%) and cytokeratin 5/6-negative group was detected in 116 (88.5%). Significant correlation was observed between cytokeratin 5/6-positive groupwith tumor size, pathologic lymph-node metastasis and American Joint Committee on Cancer staging (pT, pN and stage, P = 0.001). No association was detected between cytokeratin 5/6-positive cancerand other biological markers. Patients with cytokeratin 5/6-positive showed shorter disease-free survival (P = 0.031) and overall survival (P = 0.018) than patients with cytokeratin 5/6-negative.
Conclusion : Our results show that cytokeratin 5/6 is important markers that can be used to predict prognosis in triple-negative breast cancer. But, there is a need for larger number of cases, more immunohistochemical markers and gene investigation to observe more accurate disease free survivaland overall survival rate

목차 (Table of Contents)

• Introduction
• Materials and methods
• Patients and specimens
• Histology and immunochemistry
• Statistical Analysis
• Results
• Discussion
• Conclusion
• Acknowledgement
• Reference

참고문헌 (Reference)

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