Prognostic impact of tumor-associated neutrophils in breast cancer.

OBJECTIVES

Neutrophils are the most common type of leukocyte in mammals and play an essential role in the innate immune system and anti-cancer responses. However, recent studies identified the presence of tumor-associated neutrophils (TANs) as a poor prognostic factor. The present study investigated whether relationships exist between TANs and the clinicopathological factors and genetic status of breast cancer.

METHODS

A total of 196 breast cancer patients with sufficient biopsy, breast-conserving surgery, or mastectomy specimens between 2014 and 2021 in Hokuto Hospital were included.

RESULTS

TANs were individually counted in the tumor stroma (TS) and tumor nest (TN). A higher density of TANs in both TS and TN correlated with tumor size (TS = 0.010; TN = 0.001), a high histological grade (TS < 0.001; TN < 0.001), the histological type (TS = 0.009; TN = 0.034), a high ratio of lymph node metastasis (TS < 0.001; TN < 0.001), an advanced stage of cancer (TS < 0.001; TN = 0.002), intrinsic subtypes (TS < 0.001; TN < 0.001), (TS < 0.001; TN < 0.001), (TS = 0.002; TN = 0.023), and (TS < 0.001; TN < 0.001). A higher density of TANs in TS and TN also correlated with shorter disease-free survival and overall survival ( < 0.001).

CONCLUSION

The present results suggest that a higher density of TANs correlates with unfavorable prognostic factors in breast cancer. Further research on clinicopathological and genetic factors associated with TANs in breast cancer is needed.