Lobules are a normal part of the breast which produces milk. Lobular carcinoma in situ (LCIS) occurs when abnormal cells grow in these lobules of the breast. These abnormal cells do not grow in an uncontrolled manner or spread to other areas of the body like cancer. However, LCIS is considered a risk factor for future breast cancer.
It is not clear exactly what causes LCIS. It is probably a combination of genetics and environment.
LCIS is more common in premenopausal women, generally between 40-50 years old. Other factors that may increase your chance of LCIS include:
LCIS does not appear on imaging tests, nor can it be felt during a manual breast exam. It is generally found by accident during biopsy of other nearby breast tissue.
LCIS does not require treatment.
Frequent follow-up visits and tests to monitor any changes in the breast tissue may be recommended because of the increased risk of breast cancer. If you detect any changes in either breast, call your doctor right away for an appointment.
Other breast cancer prevention treatments may be recommended based on your overall risk of developing breast cancer. If you have a high risk of developing future breast cancer, your doctor may recommend:
Talk to your doctor about the risks and benefits of having these treatments.
American Cancer Society
National Cancer Institute
Canadian Cancer Society
Lobular carcinoma in situ. American Cancer Society website. Available at: http://www.cancer.org/healthy/findcancerearly/womenshealth/non-cancerousbreastconditions/non-cancerous-breast-conditions-lobular-carcinoma-in-situ. Updated August 24, 2012. Accessed January 24, 2014.
Lobular carcinoma in situ. EBSCO DynaMed Plus website. Available at: http://www.dynamed.com/topics/dmp~AN~T114068/Lobular-carcinoma-in-situ. Updated August 18, 2016. Accessed October 3, 2016.
Lobular carcinoma in situ. National Cancer Institute website. Available at: http://www.cancer.gov/cancertopics/pdq/treatment/breast/healthprofessional/page5. Updated November 19, 2013. Accessed January 24, 2014.
Venkitaraman, R. Lobular neoplasia of the breast. Breast J. 2010;16(5):519-528.
Last reviewed December 2014 by Michael Woods, MD
Please be aware that this information is provided to supplement the care provided by your physician. It is neither intended nor implied to be a substitute for professional medical advice. CALL YOUR HEALTHCARE PROVIDER IMMEDIATELY IF YOU THINK YOU MAY HAVE A MEDICAL EMERGENCY. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with any questions you may have regarding a medical condition.