In this BC cohort, the extent of TIL was associated with histological grade, the presence of in situ carcinoma, estrogen receptor (ER), and progesterone receptor (PR) negativity, a TLS presence and PD-L2-positivity after adjustment for multiple comparisons (Table S4 in Supplementary Material). The gene discussed is PDCD1LG2; the disease is in situ carcinoma.