Lobular neoplasia

What is lobular neoplasia? 

Breasts are made up of lobules (milk-producing glands) and ducts (tubes that carry milk to the nipple) which are surrounded by glandular, fibrous and fatty tissue. When lobular neoplasia occurs, there is an increase in the number of cells contained in the lobules, together with a change in their appearance and behaviour.

The term ‘lobular neoplasia’ describes a range of changes within the breast lobules including atypical lobular hyperplasia (ALH) and lobular carcinoma in situ (LCIS). In situ means the changes only occur in the breast lobules and do not affect the surrounding tissue.

The features of lobular neoplasia

Both ALH and LCIS are conditions where cells lining the lobules of the breast look different and multiply differently from normal cells. The appearance of ALH and LCIS under the microscope is very similar and the diagnosis depends on the degree of change that the cells have undergone and how extensive the area of abnormal cells is within the lobules. LCIS involves a more extensive area. However, it‘s sometimes difficult for even experienced pathologists to separate the two conditions and in this case it will be reported as lobular neoplasia.

Very rarely, LCIS may be made up of larger, more abnormal cells, known as pleomorphic LCIS. Pleomorphic LCIS behaves differently to other conditions included in lobular neoplasia. Pleomorphic LCIS is treated more like another breast condition called ductal carcinoma in situ.

Future breast cancer risk

Lobular neoplasia has been shown to be a marker (a signal) of an increased risk of developing breast cancer in the future in both breasts, not just the breast in which lobular neoplasia is found. However, there is some recent evidence to suggest that there is a greater risk in the area of the breast in which lobular neoplasia was found, and in some cases it may be a precursor of an invasive breast cancer. The extent of the risk depends on several factors, including:

  • your age when lobular neoplasia is diagnosed
  • the extent of the lobular neoplasia (the risk is greater with LCIS than ALH)
  • having a significant family history of breast cancer (you can find out more about this in our Breast cancer in families booklet).

The vast majority of women diagnosed with ALH or LCIS will never get breast cancer. However, people diagnosed with either condition do have a slightly higher risk than the general population of developing breast cancer at some point in their lives.

Diagnosing lobular neoplasia

Lobular neoplasia can be difficult to diagnose because most women with lobular neoplasia have no symptoms. It’s usually discovered by chance, either as calcifications (small spots of calcium salts) on a mammogram, or when a breast biopsy is taken for some other reason such as a breast lump.

Treatment and follow-up

There is no recommended standard treatment for lobular neoplasia. It’s important that you are able to discuss treatment options with your specialist, based on your particular situation.

If your lobular neoplasia is diagnosed by a core biopsy, your doctor may recommend a small operation called an excision biopsy to remove further tissue from the area where the lobular neoplasia was found. This is to confirm that there aren’t any cancer cells in the area.

Although most women who are diagnosed with lobular neoplasia do not develop breast cancer, regular follow-up with mammograms annually for up to five years is usually recommended with the aim of finding any further changes as early as possible.

Sometimes further scans may be recommended, such as an MRI (magnetic resonance imaging) scan if you have other risk factors for breast cancer such as a significant family history of breast cancer.

If you have already been shown to have an increased risk of breast cancer due to a significant family history, you may want to discuss the possibility of having a risk-reducing bilateral mastectomy (surgery to remove both breasts) with or without breast reconstruction.

Research has shown that treatment of women who have lobular neoplasia with tamoxifen (a hormonal therapy treatment for breast cancer) can reduce the risk of breast cancer developing. However, any possible benefit of taking tamoxifen needs to be considered against the risks and side effects of this treatment. Your specialist team will talk to you if this might be an option for you. 

What this means for you

Finding out that you have lobular neoplasia can leave you feeling a number of different emotions. Fear, shock and anger are all common feelings at this time. Although lobular neoplasia is not breast cancer, you may experience times when you feel anxious or negative or concerned about your future risk.

There are people who can support you, so don’t be afraid to ask for help. Let other people know how you are feeling, particularly your family and friends. It can also help to discuss your feelings or worries with your specialist team. If you want to talk through your feelings in more depth over a period of time, a professional counsellor might be more appropriate.

Your specialist or breast care nurse or your GP (local doctor) will usually be able to arrange this.

Content last reviewed December 2013; next planned review 2015