ABSTRACT
BACKGROUND: Epithelial tumor cells with a CD44(+)/CD24(-/low) immunoprofile may have the ability to cause breast cancer. We studied these cells and their clinicopathological significance. METHODS: The clinicopathologic findings of 100 invasive ductal carcinoma (IDC) cases and 45 ductal carcinoma in situ (DCIS) cases were reviewed. CD44(+)/CD24(-/low) tumor cells were identified by immunohistochemistry, and their clinicopathological implications in IDC and DCIS were analyzed. RESULTS: IDC with a high prevalence of CD44(+)/CD24(-/low) tumor cells was significantly associated with larger mass, higher grade, estrogen receptor (ER) negativity, and tumor cells with a higher frequency of metastasis. The proportion of CD44(+)/CD24(-/low) tumor cells in IDC, and its DCIS components was not significantly different, whereas the proportion of CD44(+)/CD24(-/low) tumor cells was higher in DCIS than in the DCIS component of IDC (p < 0.001). CONCLUSIONS: IDC with a high prevalence of CD44(+)/CD24(-/low) tumor cells might correlate with aggressive features, such as ER and higher grades. Moreover, the proportion of CD44(+)/CD24(-/low) tumor cells in the DCIS components of IDC and DCIS might harbor different biology, which may lead to differences in cancer progression and early carcinogenesis.