To investigate the relationship of breast cancer associated macrophages (TAMs) with clinicopathological characteristics in breast cancer, including tumor invasion and metastasis.

Eighty breast cancer tissues and matched tumor adjacent breast tissues were collected from patients treated at the Tumor Hospital of Shaanxi Province from January 2015 to August 2016. All the tissue samples were subjected to immunohistochemical staining for CD68, TGF-β1, uPA, and MMP-9, and their relationship or correlation with clinicopathological characteristics was identify by the chi-square test or Fisher exact test.

The positive expression rates of CD68, TGF-β1, uPA, and MMP-9 in breast cancer were 65.00% (52/80), 57.50% (46/80), 56.25% (45/80), and 48.75% (39/80), respectively, all of which were significantly higher than those in matched tumor adjacent breast tissues [8.75% (7/80), 10% (8/80), 12.5% (10/80), and 11.25% (9/80), respectively; P<0.001]. The positive expression rates of CD68, TGF-β1, uPA, and MMP-9 were related closely to tumor TNM stage and lymph node metastasis (P=0.038, 0.033, 0.017, and 0.025; P=0.004, 0.037, 0.005, and 0.038), respectively, but were not associated with patient age or tumor clinicaopathological type. The correlation analysis showed that there was a positive correlation between the expression of CD68, TGF-β1, and uPA in breast cancer tissues (r=0.588, P<0.001; r=0.357, P=0.001).

TAMs are highly expressed in breast cancer tissues and closely related to tumor invasion and lymph node metastasis. TAMs may be important in tumor invasion and metastasis and can be an important marker of poor prognosis in breast cancer.