Key facts about lobular carcinoma in situ (LCIS) and atypical ductal or lobular hyperplasia: ⭐️ What they are and how they increase breast cancer risk ⭐️ Do they need surgery? ⭐️ When do we think about endocrine therapy (tamoxifen or aromatase inhibitors) Bottom line: these are conditions that can increase your breast cancer  risk in the future and we think about using endocrine therapy to lower that risk. Endocrine therapy can reduce risk of future breast cancer by 50% when given for LCIS or a