Lobular Carcinoma In Situ

What is Lobular Carcinoma In Situ?

Lobular carcinoma in situ (LCIS) is a condition in which abnormal cells are found in the lobules of the breast, which are the glands responsible for producing milk. Despite its name, LCIS is not considered a true breast cancer but rather a marker indicating an increased risk of developing breast cancer in the future. LCIS is a non-invasive condition, meaning the abnormal cells are confined within the lobules and have not spread to surrounding breast tissue or other body parts.


How Does LCIS Impact Your Anatomy and Health?

LCIS itself does not cause significant changes to the anatomy of the breast or lead to symptoms typically associated with invasive breast cancer, such as lumps or changes in breast shape. However, its presence signifies a higher risk of developing invasive breast cancer in either breast. This risk extends to other types of breast cancer, not just those originating from the lobules. Therefore, the primary health impact of LCIS is the need for vigilant monitoring and possibly preventive treatment strategies to manage the risk of breast cancer.


Causes and Risk Factors for Lobular Carcinoma In Situ

The exact causes of LCIS are not fully understood, but several factors are thought to contribute to its development:

  • Age: LCIS is more commonly diagnosed in premenopausal women, typically between the ages of 40 and 50.
  • Family History: Women with a family history of breast cancer, especially those with relatives who had LCIS or invasive lobular carcinoma, are at a higher risk.
  • Hormonal Factors: Long-term exposure to oestrogen, which can occur with early menstruation, late menopause, or hormone replacement therapy, may increase the risk.
  • Genetic Factors: While less directly linked than in invasive breast cancer, genetic predispositions due to mutations in genes like BRCA1 and BRCA2 might increase the risk of LCIS.
  • Reproductive History: Early age at first menstruation, late menopause, and having children later in life or not at all can increase the duration of oestrogen exposure, potentially raising the risk of LCIS.


Symptoms of Lobular Carcinoma In Situ

LCIS is typically asymptomatic, meaning it usually does not present any noticeable symptoms. Most cases of LCIS are discovered incidentally during a biopsy performed for other reasons, such as an abnormal mammogram or an unrelated breast tissue. Because LCIS does not form a lump or mass or cause changes to the skin or feel of the breast, it is not usually detectable through breast self-exams or clinical breast exams.


Diagnosis of Lobular Carcinoma In Situ

LCIS is often diagnosed incidentally during biopsies that are conducted for other reasons, such as an unrelated breast lump or an abnormal mammogram. Here are common methods used in the diagnosis:

  • Mammography: LCIS typically does not appear on mammograms because it does not form a mass or calcification. However, mammograms may be conducted for other abnormalities that lead to the discovery of LCIS.
  • Biopsy: The definitive diagnosis of LCIS is usually made through a biopsy. When breast tissue is removed during a biopsy for any suspicious area identified through imaging or physical examination, the tissue is examined microscopically to look for abnormal cells within the lobules.
  • Magnetic Resonance Imaging (MRI): An MRI can assess the extent of LCIS in the breast, particularly in patients with a known diagnosis, to help guide management decisions.


Treatment of Lobular Carcinoma In Situ

Treatment for LCIS focuses on surveillance and prevention of breast cancer rather than direct treatment of LCIS itself. The standard approaches include:

  • Regular Monitoring: This involves periodic clinical breast exams and annual mammograms to monitor for any signs of breast cancer.
  • Medications: For women at higher risk of breast cancer, doctors may recommend hormone-blocking drugs such as tamoxifen or raloxifene to reduce the risk of developing invasive breast cancer.
  • Surgical Options: In cases where there's a strong family history of breast cancer or genetic factors like BRCA mutations, prophylactic bilateral mastectomy may be considered to reduce the risk of breast cancer significantly.


Risk of Developing Lobular Carcinoma In Situ

The risk is about 1% to 2% per year, meaning that over 20 years, the risk could accumulate to approximately 20-40%. Women with LCIS must engage in active surveillance or consider preventive treatments to manage their increased risk of breast cancer.