Clinicopathological features and prognostic factors associated with metaplastic carcinoma of the breast / 中华普通外科杂志

ABSTRACT

Objective:To study the clinicopathological features of metaplastic breast cancer (MBC) , and its prognostic factors.Methods:Data of 49 MBC cases and 30 cases of invasive ductal carcinoma (IDC) during the same period as matched control were collected. The immunohistochemistry staining of CK5/6, CK, P63, ER, HER2, Ki67 was performed in all MBC samples.Results:In MBC cases, the median age was 55 years. Median tumor size was 2.5 cm (range, 0.6-19 cm). Fifteen cases were classified as metaplastic carcinoma with heterologous mesenchymal differentiation (8 as matrix-producing carcinoma), 12 as spindle cell carcinoma, 7 as squamous cell carcinoma, 2 as low-grade adenosquamous carcinoma, 2 as fibromatosis-like metaplastic carcinoma, and 11 as mixed metaplastic carcinoma. The 5-, 10-year overall survival rate was 50%, 41%, respectively, lower than those of IDC (76%,63%) (all P<0.05). Lymph node metastasis rate, and expression of ER, PR, HER2 in MBC were lower than those in IDC (all P<0.05). Triple-negative cases in MBC were more than those of IDC ( χ2=26.244, P=0.000). The proliferative index of Ki67 was statistically different between the two groups ( t=2.624, P=0.011). Conclusions:MBC is a rare and heterogenous breast cancer. Compared to IDC, MBCs are usually larger, lower in lymph nodes metastasis, higher in proliferative index of Ki67, more triple-negative, hence with a poorer prognosis.