What to expect from risk-reducing endocrine therapy for lobular carcinoma in situ

Lobular carcinoma in situ, or LCIS, is an abnormal change in cells inside the breast lobules. It is a marker of increased future breast cancer risk rather than an invasive cancer. Endocrine therapy acts on hormone-sensitive pathways and can be offered as part of a wider risk-reduction plan. It does not remove existing breast tissue or replace breast imaging.

Before starting, your clinician may review menstrual or menopause status, medicines, clotting history, bone health and other conditions. Possible effects vary by medicine and may include hot flushes, night sweats, vaginal symptoms, mood changes, joint discomfort or changes in bone strength. Discuss any new symptom rather than stopping treatment without advice.

Ask which medicine is being proposed, how it is taken, and how long the planned course may last. Keep an up-to-date list of prescriptions, supplements and allergies. Arrange the breast examination and imaging follow-up recommended for your risk profile. A symptom diary can help you and your clinician decide whether an adjustment, supportive measure or different option is appropriate.

You can read more about the approach in [Risk-Reducing Endocrine Therapy](/treatments/risk-reduction-and-prevention/risk-reducing-endocrine-therapy/).

Contact your care team promptly for unusual bleeding, a new breast change, severe or persistent mood symptoms, or troublesome pain. Seek urgent help for sudden chest pain, difficulty breathing, coughing blood, or one-sided leg swelling and pain, because these symptoms can signal a serious problem.

Which endocrine therapy fits my medical history? What benefits and side effects should I weigh? How will you monitor bone health or other risks? What should I do if I miss a dose or want to stop? Which breast imaging schedule is right for me?