Is overexpression of CD163 and CD47 in tumour cells of breast carcinoma implicated in the recruitment of tumour-associated macrophages (TAMs) in tumour microenvironment? immunohistochemical prognostic study.

Background: Now, targeted therapy and immunotherapy are promoted. tumour -Associated Macrophages (TAMs) are an essential component of immune-response in breast cancer(BC) with prognostic controversy. Additionally, their recruiting factors are still obscure. Purpose:This study aimed to evaluate the prognostic significance of CD163 and CD47 in BC of No Special Type (BC-NST) and to explore their suggested role in recruiting TAMs.

Material and methods: This immunohistochemical study was conducted on 91 archival specimens of breast cases. Immunoreactivity scores were correlated with TAMs density, clinicopathological data, and survival.

Results: Revealed the highest CD163 expression was detected in the pure DCIS group (p = 0.016), while the highest CD47 expression and high TAMs density were reported in the invasive group (p = 0.008, and p = 0.002 respectively) followed by the DCIS group. In IC-NSTs the CD163 and CD47 scores were associated with poor prognostic parameters like(high grade, advanced stage, distant metastasis, ER negativity,Ki67 index, post-surgical chemotherapy, poor NPI group, high mitotic count, dense infiltration of TAMs, shorter OS). Also, CD47 was associated with the dens infiltration of TAMs in DCIS (p = 0.001). There was a significant correlation between tumour cell expression of CD163 and CD47 in IC-NSTs and DCIS (p = 0.002 and p = 0.009 respectively).

Conclusions: High CD163 and CD47 expressions in both DCIS andIBC are intimately associated, significantly associated with poor prognosis and are important provoking factors of TAMs.