Lobular carcinoma in situ

If you've been diagnosed with lobular carcinoma in situ (LCIS), you'll need expert advice on your situation. The following general information may not cover your situation exactly.

What is lobular carcinoma in situ?

Lobular carcinoma in situ (LCIS) is an uncommon condition where benign (non-cancer) change is seen within the lobules of the breast.

The lobes or lobules are the milk-producing glands that cluster like bunches of grapes at the far end of the milk ducts in the breast. Under a microscope, normal lobes look empty. When a number of the lobes appear crowded with cells, the condition is called lobular carcinoma in situ.

Although the term 'carcinoma in situ' can arouse anxiety and thoughts of cancer, LCIS is considered a benign condition that doesn't usually require treatment. There are a number of reasons for this. The multiple cells in the lobes are regular in shape, unlike cancer cells. In addition, the cells are confined to the lobes ('in situ' means in place). However, long-term follow-up is recommended after a diagnosis of LCIS.

lobular carcinoma in situ

Finding lobular carcinoma in situ

LCIS doesn't usually form a lump or show up on a mammogram. It's found by chance when a sample of breast tissue is removed to investigate a breast symptom of some kind. When a pathologist examines the tissue under a microscope, a number of the lobes appear packed with cells.

Lobular carcinoma in situ and the risk of breast cancer

LCIS is not invasive breast cancer. However, research has shown that some women diagnosed with LCIS may later develop breast cancer, which can occur in either breast, sometimes many years later. If breast cancer does occur after a diagnosis of LCIS, it can be either ductal or lobular cancer. The risk is a moderate one, and most women with LCIS will not develop breast cancer.

So, although LCIS itself doesn't usually require treatment, it's a marker for increased risk. For this reason, your doctor will advise you about regular, long-term follow-up. Usually this will mean annual mammograms as well as regular breast checks by a doctor. You may want to learn to check your own breasts for signs of unusual change, or improve your technique—ask your doctor about this.

Hormone replacement therapy

Women with a diagnosis of LCIS may think about taking hormone replacement therapy (HRT) if they're troubled by symptoms arising from menopause. Although the risks are unclear, the benefits of HRT can be important for individual women. If you're considering taking HRT, discuss your situation with your doctor. In particular, ask about the appropriate dosage, the length of time to continue taking HRT, and any other preparations that may help with problems arising from menopause.

You can also ring the Cancer Council on 13 11 20 to discuss questions of concern to you.

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