FOXP3 and breast cancer: Both CD8/FOXP3 and CD8/eTreg values were significantly decreased in breast cancer TILs compared to those of PBMC and LNBT (CD8/FOXP3 ratios: PBMC 38.11 [IQR: 26.23–53.2], LNBT 44.28 [IQR: 39.89–56.94] vs breast cancer TILs 3.16 [IQR: 2.69–4.90]; CD8/eTreg ratios: PBMC 113.82 [IQR: 89.43–145.2], LNBT 136.64 [IQR: 99.12–163.18) vs breast cancer TILs 7.86 [IQR: 4.08–12.80], all P < 0.05) (Fig. 1a).