Lobular carcinoma in situ (LCIS)


Normally, LCIS usually not be seen on a mammogram but it may already be present in one or both breasts. It is usually found by chance when you undergo breast biopsy for another reason of the breast that has abnormalities.
There are 2 types of breast biopsy:

    • Core needle biopsy. This type of biopsy is performed by a surgeon or radiologist with the help of imaging procedures such as an ultrasound or Magnetic Resonance Imaging (MRI) using a needle to remove a sample of the affected tissue.
    • Surgical biopsy. The affected tissue of the breast is removed by surgery.

The sample tissue is then sent to the lab where the pathologist analyzes the cells to know if LCIS is present.


Your own choice of treatment and many other factors are considered when deciding on which treatment to use for LCIS.
The treatment options used:

  • Close observation
  • Preventive therapy by medication
  • Surgery


The doctor will suggest to undergo examinations regularly to watch out for any signs of breast cancer. These examinations are as follows:

  • Breast self-examination every month to check for any abnormalities
  • Breast examination every year by a health professional for a clinical assessment
  • Yearly mammogram
  • Diagnostic imaging such as MRI of the breast or molecular breast imaging, especially for patients with high risk of acquiring breast cancer (e.g., family history of breast cancer)

Preventive therapy

Using medication to decrease the risk of breast cancer (chemoprevention). The following therapies may be done:

    • Selective Estrogen Receptor Modulator (SERM) medications. Used to block the attachment of hormones such as estrogen to cancer cells. It will avoid the growth and development of breast cancer. One example of SERM is Tamoxifen which decreases the risk of breast cancer occurrence in women during premenopausal and postmenopausal period. For postmenopausal women, Raloxifene is the drug of choice to decrease the risk of acquiring breast cancer, and it is also used to treat or prevent osteoporosis.
    • Aromatase inhibitors. Uses medications that prevents estrogen production of the body because the breast cancer cells use estrogen to grow and survive. Anastrozole and exemestane are aromatase inhibitors that decreases the risk of acquiring breast cancer in women in their postmenopausal period. Research has shown that these medications help decrease breast cancer risk for those women with higher risk.

Talk to your doctor in order to find out your risk and to come up with the best medical treatment option for you.


In some patients, surgery may be done, especially in high risk types of LCIS such as Pleomorphic Lobular Carcinoma in Situ (PLCIS). This type of LCIS can be detected in mammogram. The surgery may require removing only the part with PLCIS (lumpectomy) or remove the whole breast tissue (mastectomy). The surgeon decides the surgical technique based on your age, the extent of PLCIS and your family history. In some cases, the doctor may suggest radiation therapy after lumpectomy by referring you to a radiation oncologist to talk about your condition and treatment option.

LCIS may also be treated by undergoing preventive (prophylactic) mastectomy which does not only remove the affected part but takes out both of the whole breasts. This ensures that there is less risk of acquiring breast cancer because LCIS poses more risk of having breast cancer.