The Relationship Between the Expression of Cytokeratin 5/6 and Clinicopathologic Factors in Invasive Breast Carcinoma

The document reports on a study that investigated the relationship between cytokeratin 5/6 (CK 5/6) expression and clinicopathologic factors in invasive breast carcinoma. The study involved an immunohistochemical analysis of tissue microarrays constructed with 91 invasive carcinoma samples from a total of 179 invasive breast carcinomas collected from 2005 to 2008. The results showed that 13.2% (12/91) of the cases were basal-like tumors, which were significantly associated with negative estrogen receptor (ER) status, negative progesterone receptor (PR) status, and high histologic grade (p=0.001, 0.001, and 0.004, respectively). Other factors such as patient age, tumor size, lymph node involvement, stage, and HER2/neu expression were not significantly associated with this subtype (p>0.05). The study concluded that CK 5/6 expression was more likely to be found in tumors with negative ER status and high histologic grade, which limits the range of adjuvant therapies available. The authors suggested that further research with more specimens is needed to assist in treatment and studies of this tumor subtype and to explore the relationship between CK 5/6 expression and breast cancer stem cells.