Moreover, high TILs density and high stromal PDL1+ expression could categorise high risk DCIS defined as high grade DCIS and >15 mm in size into two distinct groups with different outcome; whereas high TILs and stromal PDL1 + cells were associated with shorter LRFI in these patients (HR = 3.2, 95%CI = 1.1–9.5, p = 0.039, and HR = 2.5, 95%CI = 1.1–6.3, p = 0.044, respectively) (Supplementary Fig. 4). This evidence concerns the gene CD274 and ductal breast carcinoma in situ.