PGR and ductal breast carcinoma in situ: The Tlsty group has analysed the expression of p16, COX2 and Ki67 to identify an IHC based predictor for the likelihood of recurrence.17 In a multivariable model, DCIS lesions that were p16+/COX2+/Ki67+ or those detected by palpation were statistically significantly associated with subsequent invasive cancer.17 Based on these initial analyses, they have identified a panel of IHC biomarkers (PR, HER2, Ki67, COX2, p16/INK4A, FOXA1 and SIAH2), which is commercially available through Prelude’s CLIA-approved lab as DCIS on RTTM (Decision score (DS)).