Some studies by Diadone, Gennari and another by Fischer in 1997 [46,47,48] have shown that older patients had tumours with more favourable biological features such as a lower proliferation rate, normal p53 and higher expression of oestrogen and progesterone receptor status and the proportion of ER positive tumours in older women being more than 80%. This evidence concerns the gene ESR1 and neoplasm.