This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Endocrinology and breast, Subject name: Surgery
[{'content': 'Tamoxifen given in breast carcinoma for \nSelect and explain. \nA. 2 years, B. 3 years, C. 5 years, D. Lifelong', 'role': 'user'}, {'content': 'Answer: C \nExplanation: Women with hormone receptor-positive tumours will obtain a wohwhile benefit from at least 5 years of endocrine therapy, either 20 mg daily of tamoxifen if premenopausal or the Aromatase Inhibitors (anastrozole, letrozole, and exemestane) if postmenopausal. Recent trials have shown that longer durations of endocrine therapy provide a small extra benefit but with increased toxicity.It is no longer appropriate to give hormone therapy to women who do not have oestrogen or progesterone receptor-positive disease. Ref: Bailey and Love, 27e, page: 878', 'role': 'assistant'}]