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Macmillan and Cancerbackup merged in 2008. Together we provide free, high quality information for people affected by cancer through our publications, website and phone service. Find out more| .
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This information is about lobular carcinoma in situ (LCIS). It should ideally be read with our general information about breast cancer| .
Lobular carcinoma in situ (LCIS) is not a cancer, but women who have LCIS have an increased risk of developing breast cancer in the future. Even so, most women with LCIS don't develop breast cancer.
LCIS may be in one or both breasts. The cancer risk is the same for both breasts regardless of which breast LCIS is found in.
Each breast contains hundreds of tiny lobules where milk is produced. With LCIS, there are changes in the cells lining the lobules or lobes of the breast. It is often present in both breasts. LCIS is more common in women who have not reached their menopause (change of life).
The structure of the breast
LCIS doesn't show up on a mammogram| (breast x-ray). It is usually discovered as a chance finding, when a sample of breast tissue is taken and examined under a microscope (biopsy| ), or when a breast lump is removed.
If you had a fine needle aspiration or a core needle biopsy (the doctor used a needle to take a small piece of tissue from the abnormal area) you may need an operation to remove a larger area of tissue. This is called an excision biopsy. It may be done to make sure that there are no other changes within the breast tissue such as precancerous changes (called DCIS) or an invasive cancer.
The abnormal area is removed under a general or local anaesthetic and sent to a laboratory for examination under a microscope. This may mean an overnight stay in hospital, but it is done as day surgery in some hospitals.
If a lump is too small to be felt but has shown up on an ultrasound, the radiologist may need to mark the area for the surgeon before the excision biopsy. This is done by inserting a very small wire (a guide wire) under local anaesthetic, using x-ray or ultrasound guidance. The procedure is known as wire localisation.
Women don't usually need any treatment when LCIS is diagnosed. And, because the majority of women with LCIS don't develop breast cancer, most will never need treatment.
Doctors recommend that women with LCIS have breast examinations every 6–12 months, and mammograms every 1–2 years. This is so that if there are any changes in the breast they are detected at the earliest stage and treated if appropriate.
A recent research study found that the hormonal therapy tamoxifen can reduce the risk of breast cancer developing in women with LCIS. But, it's still not clear if the benefits of taking it outweigh the possible risks and side effects it can cause.
A second research trial, known as IBIS2, is being carried out to see whether another type of hormonal therapy, called anastrozole| (Arimidex®), can also reduce the risk of breast cancer developing in post-menopausal women who have an increased risk. This trial includes women with LCIS.
Rarely, a woman with LCIS may decide to have both breasts removed (bilateral mastectomy| ). This tends to happen where there is a strong family history| of breast cancer, or the woman is extremely anxious about her risk of developing breast cancer.
Research into treatments for LCIS is ongoing, and advances are being made. Cancer doctors useclinical trials| to assess new treatments. Before any trial is allowed to take place, an ethics committee must have approved it and agreed that the trial is in the interest of patients.
You may be asked to take part in a clinical trial. Your doctor must discuss the treatment with you so that you have a full understanding of the trial and what it involves. You may decide not to take part, or withdraw from a trial at any stage.
You may experience many different emotions| , including anger, resentment, guilt, anxiety and fear. These are all normal reactions, and are part of the process many people go through in trying to come to terms with their illness.
This section has been compiled using information from a number of reliable sources, including:
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