Lobular Carcinoma In Situ (LCIS)

Lobular carcinoma in situ (LCIS) is a relatively uncommon condition in which abnormal cells develop in the milk-producing glands (lobules) of a breast. Despite the word “carcinoma” in its name, LCIS is not a precancerous or cancerous condition. For this reason, it is no longer referred to as “stage 0 breast cancer.”

Tampa General Hospital’s Cancer Institute offers world-class care for breast conditions—both benign and cancerous—through our renowned Breast Cancer Center. Our comprehensive services include the latest options in risk assessment, prevention, screening, diagnosis, treatment and supportive care. TGH is proud to be ranked among the top 10% of hospitals in the United States for Cancer care by U.S. News and World Report for 2023-24.

What Is Lobular Carcinoma In Situ?

Also known as lobular neoplasia, lobular carcinoma in situ is the development of abnormal but noninvasive cells in the lobules of a breast. The atypical cells remain confined to the lobule where they developed (in situ) and do not spread into the surrounding breast tissues.

While lobular carcinoma in situ is not breast cancer, it is a marker for increased breast cancer risk. On average, a woman’s lifetime risk of developing breast cancer is 12%. In comparison, a patient who is diagnosed with LCIS is approximately 30% more likely to develop breast cancer in the future.

LCIS vs. DCIS

Like lobular carcinoma in situ, ductal carcinoma in situ is a noninvasive breast condition. While LCIS develops in the lobules, DCIS develops in the tubes that carry milk to the nipple (milk ducts). In both cases, the abnormal cells remain in place (in situ) and do not spread beyond the lobule or milk duct where they developed.

Unlike LCIS cells, DCIS cells often contain small particles of calcium (microcalcifications), which makes the condition easier to spot in a mammogram. LCIS can be more challenging to detect.

Compared to LCIS, DCIS is more common and more likely to progress into breast cancer. LCIS is considered to be a risk factor for breast cancer, while DCIS is considered to be a precursor to breast cancer.

What Causes Lobular Carcinoma In Situ?

The causes of lobular carcinoma in situ are unknown. Through extensive research, scientists have identified several risk factors for LCIS, including:

  • Advanced age (most cases are diagnosed after age 40)
  • A family history of breast cancer
  • The use of hormone therapy after menopause

    • Lobular Carcinoma In Situ Symptoms

    Lobular carcinoma in situ does not produce noticeable symptoms or mammogram features. The unusual pattern of cell growth can only be seen during the microscopic evaluation of the breast tissue. In most cases, LCIS is an incidental finding in a breast biopsy performed for an unrelated reason, such as to evaluate a suspicious breast lump.

    How Is Lobular Carcinoma In Situ Diagnosed?

    Usually, lobular carcinoma in situ is diagnosed with a needle biopsy, which may be performed with real-time imaging guidance. After numbing the breast area, a physician inserts a fine, hollow needle and removes a small sample of breast tissue. The sample is then sent to a lab, where a pathologist uses a microscope to examine the cell characteristics in detail.

    Lobular Carcinoma In Situ Treatment

    After confirming a diagnosis of lobular carcinoma in situ, a physician may recommend more frequent breast cancer screenings, including clinical breast examinations and mammograms, and possibly prescribe a medication such as tamoxifen to help prevent the abnormal cells from transitioning into cancer.

    In some cases, an excisional biopsy may be considered to remove the abnormal tissue in its entirety while preserving as much healthy breast tissue as possible. Additionally, a patient who is at high risk for developing breast cancer due to their family history or a BRCA gene mutation may elect to undergo a preventive mastectomy.

    LCIS Survival Rate

    People who are diagnosed with lobular carcinoma in situ have a very good prognosis. With careful monitoring by an experienced physician and appropriate treatment when necessary, a patient with LCIS can remain healthy and cancer-free.

    Receive World-Class Care at TGH

    At TGH, we understand that waiting for the results of a biopsy can be stressful for a patient, and we do everything possible to expedite the diagnostic process and ensure streamlined care. If would like to learn more about lobular carcinoma in situ, contact us at (800) 844-4554 to request an appointment with a specialist.