Using IHC, low Ki67 (<10 %) was associated with a reduced risk of recurrence, with a HR of 0.88 (95 %CI: 0.38–2.04, Fig. 6a) and a corresponding HR of 0.71 (95 %CI: 0.26–1.94) after adjusting for baseline PgR status, tumor size, and age. This evidence concerns the gene PGR and neoplasm.