Breast cancer health centre

Lobular carcinoma (invasive and in situ)

Lobular carcinoma is a type of cancer or abnormal cells affecting milk glands called lobules in a woman's breasts.

Lobular carcinoma can be classed as invasive or in situ.

What is lobular carcinoma in situ?

Lobular carcinoma in situ (LCIS) is technically not cancer. LCIS, though, is often thought of as a form of breast cancer.

Lobular carcinoma in situ results in the presence of abnormal cells in the milk producing glands of the breasts. These cells rarely spread outside of the lobules to other parts of the breast or body.

Most women who are diagnosed with lobular carcinoma in situ have not yet gone through menopause. In one out of every two cases, multiple lobules within the breast are affected. About a third of the time, there are areas of lobular carcinoma in situ in both breasts.

Even though lobular carcinoma in situ can’t spread, it is important to keep an eye on the condition. About 30% of women with this condition will develop invasive carcinoma within 15 to 20 years. The majority of these later cancers begin in the milk ducts, rather than the lobules.

How is lobular carcinoma in situ diagnosed?

Lobular carcinoma in situ usually has no symptoms. Often, it’s not even detected by routine screening mammograms. This is because, unlike other breast cancers and related conditions, LCIS does not result in the formation of calcium deposits in certain breast cells.

Lobular carcinoma in situ is most commonly diagnosed after a biopsy. Typically, the biopsy has been done to assess some other abnormality detected by physical examination or mammogram.

Biopsy findings for LCIS can be very similar to an actual breast cancer called ductal carcinoma in situ. Because of this, you may want to consider asking for a second opinion to confirm your diagnosis.

How is lobular carcinoma in situ treated?

The majority of women with lobular carcinoma in situ will not need immediate treatment with surgery or drugs. Instead, your doctor will probably recommend keeping a close eye on your condition. That will mean regular breast self-examinations, clinic visits, and mammograms.

Under certain circumstances, your doctor may discuss the use of anti- oestrogen drugs. These drugs are often used for women with a family history of breast cancer who are at an increased risk of the disease. The drugs reduce the likelihood that you will develop invasive breast cancer.

Some women opt to undergo preventive surgery. That kind of surgery is called a prophylactic mastectomy. The procedure removes one or both breasts. Doing so significantly reduces the risk of breast cancer in the future.

What is invasive lobular carcinoma?

Invasive lobular carcinoma is the second most common form of invasive breast cancer. It accounts for about 10% of invasive breast cancers. The condition typically begins in one of the breast lobules. It then spreads to other parts of the breast. For some women, invasive lobular carcinoma is present in both breasts. It can also spread to other areas in the body.