When investigating OC, it is crucial to consider oestrogen levels within both serum and tumour tissues as postmenopausal women’s normal or neoplastic ovarian tissues exhibit median concentrations ∼100 times higher (ranging from 9.25 to 16.44 pmol/g) than serum levels (ranging from 0.07 to 0.10 pmol/g), and while tumoral E2 concentrations were lower in borderline and cancerous tumours than normal or benign, the opposite was true for serum concentration levels [141]. The gene discussed is BGLAP; the disease is neoplasm.