RESUMO
Objective To elucidate the differences between invasive micropapillary carcinoma (IMPC) and invasive ductal carcinoma(IDC),and explore the clinicopathological and immunohistochemistry characteristics of invasive micropapillary carcinoma of the breast.Methods Invasive micropapillary carcinoma was identified in 51 patients by retrospective review of database from October 2004 to November 2007.Data were compared with 102 patients identified as invasive ductal carcinoma available in this hospital during the same period.Results Significant differences were observed in mammilla invasion,lymphatic vessel invasion,positivity of lymph node,lymph node metastatic level,extranodal extension,estrogen receptor,progestin receptor,triple negative between the two groups; while there was no significant differences between the two groups as to amenorrhea status,lesion laterality,number of metastatic lymph nodes,human epidermal growth factor receptor-2,local recurrence and distant organ metastasis.The median follow-up time of the invasive micropapillary carcinoma group were 46 months ( 16 - 75 months),and the 3-year overall survival and disease free survival was 90.2％ and 84.3％,respectively.Conclusions Invasive micropapillary carcinoma is a unique subtype of breast cancer which manifests an aggressive behavior tending to involve lymph node and extranodal soft tissues.Invasive micropapillary carcinoma of the breast had high expression of hormonal receptors,and triple negative breast cancer is less common in this type of breast cancer.