CD4 and breast carcinoma: The proportion of eTregs and non-Tregs among CD4 + TILs was significantly higher in breast cancer TILs compared to those of PBMC or LNBT (mean eTreg of breast cancer TILs: 25.6% [IQR: 312.2–29.1%] vs PBMC: 4.2% [IQR: 3.5–5.2%] and LNBT: 4.0% [IQR: 3.9–5.1%]; mean non-Treg of breast cancer TILs: 5.2% [IQR: 3.2–9.8%] vs PBMC: 2.4% [IQR: 2.1–3.1%] and LNBT: 4.9% [IQR: 3.6–7.1%]) (Fig. 1c).