Therefore the aims of this study are to assess the importance of LRH-1 in situ and invasive breast cancer, in particular to investigate (1) NR5A2 transcript expression in invasive breast cancers (2) the role of DNA methylation in regulating the expression of NR5A2, (3) the level and pattern of expression of LRH-1 protein in a cohort of ductal carcinoma in situ (DCIS) and invasive breast carcinomas to assess its potential role in tumour progression and (4) the relationship between LRH-1 expression and clinicopathological features. The gene discussed is NR5A2; the disease is invasive breast carcinoma.