CYP19A1 and lung cancer: This implies that late menopause increases susceptibility to lung cancer.[14–16] In recent studies, menopausal women aged >60 years with lung cancer were shown to have a higher expression of aromatase (up to 84.76%), which is a key enzyme for synthesis of estrogen.[17] Especially, serum concentration of estrogen in patients with lung cancer was significantly higher than those in healthy controls.[18] Female menopause entails a decline in ovarian function, a change that gradually develops over the last few periods.