Lobular carcinoma in situ (LCIS) is a rare condition where you have abnormal cells in your lobules—the glands that produce breast milk. Lobular carcinoma in situ (LCIS) isn’t breast cancer. But it is a marker or indication that you have greater risk for developing breast cancer than those who don’t have LCIS.
Lobular carcinoma in situ (LCIS) is a rare condition that happens when you have abnormal cells in your lobules — the glands that produce breast milk. These abnormal cells are in situ, meaning they haven’t spread to surrounding breast tissue.
Lobular carcinoma in situ (LCIS) isn’t breast cancer. But it’s a marker or indication that you have greater risk for developing breast cancer than someone who doesn’t have LCIS. If you have lobular carcinoma in situ, you are 10 times more likely to develop breast cancer than someone who doesn’t have LCIS.
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Lobular carcinoma in situ is relatively rare, occurring in between four and 11 females per 100,000. It’s even less common in males. Approximately one male in 100,000 male develops breast cancer, and LCIS represents 2% of those breast cancer cases.
LCIS is most often diagnosed in people ages 40 to 60.
Lobular carcinoma in situ (LCIS) is not considered pre-cancerous or a pre-cancer. That’s because abnormal cells in your breast lobules rarely spread to surrounding breast tissue. Lobular carcinoma in situ does increase your risk of developing breast cancer.
Ductal carcinoma in situ (DCIS) is abnormal cells in your breast ducts. Like LCIS, it is a marker or indication for breast cancer. But DCIS is more likely than LCIS to spread from your breast ducts into surrounding breast tissue.
Lobular carcinoma in situ doesn’t have symptoms. It can’t be felt during breast examinations or detected by mammograms. Instead, LCIS is often discovered during tests for other conditions. For example, your healthcare provider might find LCIS while performing a biopsy to evaluate a lump in your breast.
Lobular carcinoma in situ is abnormal cells in your breasts’ milk glands. Researchers don’t know what triggers the change from a normal cell to an abnormal cell.
Many times lobular carcinoma in situ is discovered during tests for other conditions. If providers find suspected abnormal cells while doing a biopsy, they will remove the abnormal cells for additional examination.
Your treatment depends on the kind of LCIS you have, your personal health and medical history and your personal choice. Treatments include:
You might consider prophylactic surgery if you have a family history of breast cancer, meaning your parents, siblings or children were diagnosed with cancer in both breasts or were diagnosed before age 50. You might also consider a prophylactic mastectomy if several family members have had breast or ovarian cancer.
Unfortunately, researchers don’t have enough information about LCIS to recommend ways to prevent it. But there are steps you can take to reduce their risk for developing breast cancer:
Unfortunately, being diagnosed with LCIS means you’ll live with an elevated risk for breast cancer for the rest of your life. That risk increases over time. For example, one study showed that 8% of women with LCIS developed invasive breast cancer five years after diagnosis. That percentage increased to 20% 15 years after diagnosis.
There are treatment options that might reduce the risk your LISC will become breast cancer. Talk to your healthcare provider about treatment options. Understanding your options will help you feel more confident about your plan for living with LCIS.
There’s a lot you can do to take care of yourself if you have LCIS:
You should contact your healthcare provider when you notice changes in your breasts.
Lobular carcinoma in situ is a rare disease that increases your risk for developing breast cancer. Understanding your risk and your options can help you feel more confident and in control of your situation. Start with asking the following questions:
A note from Cleveland Clinic
Lobular carcinoma in situ (LCIS) isn’t breast cancer. Being diagnosed with LCIS doesn’t mean you will develop breast cancer. It does mean you live with an increased risk for developing breast cancer. You might feel frustrated and frightened because you don’t have a clear idea what to expect. If that happens, ask your healthcare provider for help understanding what it means to live with LCIS. They will have insight into your individual situation, and they can make recommendations for programs and services that might be helpful.
Last reviewed by a Cleveland Clinic medical professional on 09/20/2021.
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