Definition

Lobules are the part of the breast that produces milk. Lobular carcinoma in situ (LCIS) is when there are abnormal cells in the lobules of the breast. These abnormal cells do not grow in an uncontrolled way or spread to other parts of the body like cancer. But, LCIS is a risk factor for future breast cancer.

Causes

It is not clear what causes LCIS. It is likely due to a change in a gene.

Risk

LCIS is more common in premenopausal women who are between 40-50 years old.

Symptoms

LCIS does not have symptoms.

Diagnosis

LCIS does not appear on imaging tests. It can’t be felt during a breast exam. It is usually found during a biopsy of other nearby breast tissue.

Treatment

LCIS does not require treatment.

Your doctor will monitor your breast for changes with:

  • A physical and breast exam every 6-12 months
  • A yearly mammogram

Prevention

Take these steps to reduce your overall risk of breast cancer:

  • Exercise regularly.
  • Eat a healthful diet.
  • Maintain a healthy weight.
  • Avoid or limit alcohol. This means 1 drink or less a day for women and 2 drinks or less a day for men.
  • Follow your doctor’s guidelines for regular breast cancer screening.