breast lobular carcinoma

What is Breast Lobular Carcinoma?

Breast lobular carcinoma, also known as invasive lobular carcinoma (ILC), is a type of breast cancer that starts in the milk-producing gland, or lobules, of the breast and has spread into surrounding breast tissue. It accounts for about 10% to 15% of all breast cancers and is the second most common type of breast cancer.

Characteristics of Breast Lobular Carcinoma

• Origin: Breast lobular carcinoma originates in the milk-producing glands (lobules) of the breast.
• Spread: The cancer cells have broken out of the lobule where they began and spread into the surrounding breast tissue.
• Cell structure: Invasive lobular carcinoma is composed of non-cohesive cells individually dispersed or organized in a single-file linear pattern in a fibrous stroma.

Prevalence and Demographics

• Frequency: Breast lobular carcinoma accounts for about 10% to 15% of all breast cancers.
• Demographics: It is more common in women, but can occur in men. However, it is very rare for a man to have an invasive lobular type of breast cancer.

Association with Other Conditions

• Lobular carcinoma in situ (LCIS): Breast lobular carcinoma is often associated with LCIS, which is an uncommon condition where abnormal cells form in the milk glands (lobules) in the breast.
• Increased risk: Being diagnosed with LCIS indicates that you have an increased risk of developing breast cancer.

Treatment and Prognosis

• Hormone-driven: Breast lobular carcinoma can be treated with endocrine therapy, as it is hormone-driven in about 95% of cases.
• Immunologically hot: The immune system recognizes the tumor, making it immunologically hot.
• Prognosis: Tumors are generally of a good prognostic phenotype, being low histological grade and low mitotic index, hormone receptor positive and HER2-negative.

References

• Mouabbi et al. (2024) - A review found that 95% of lobular breast cancers are hormone-driven.
• MSK Breast Program (2024) - A new program at Memorial Sloan Kettering Cancer Center focuses on lobular breast cancer, which has its own unique features requiring a different approach to screening, diagnosis, and treatment.

Symptoms of Breast Lobular Carcinoma

Breast lobular carcinoma, also known as invasive lobular carcinoma, can cause a range of symptoms, although some cases may not exhibit any signs at all. The following are the common symptoms associated with this type of cancer:

• Hard or thickened area inside the breast or underarm: This is one of the most common symptoms of invasive lobular carcinoma (ILC) [6].
• Dimpling, dent, or puckering of the skin: ILC can cause changes in the texture and appearance of the skin over the breast, leading to dimpling or thickening [3].
• **Swelling of all or part of

Diagnostic Tests for Breast Lobular Carcinoma

Breast lobular carcinoma, also known as invasive lobular carcinoma (ILC), can be diagnosed using various diagnostic imaging tests and a breast biopsy.

• Imaging Tests: The most common and best way to detect and diagnose ILC is through Magnetic Resonance Imaging (MRI) [7]. MRI provides detailed images of the breast tissue, making it an effective tool for detecting this type of cancer.
• Breast Biopsy: A breast biopsy is usually performed when a lump or abnormality is detected in the breast. During the biopsy, small pieces of breast tissue are removed and examined under a microscope [6]. This is often how LCIS (lobular carcinoma in situ) is diagnosed.
• Other Diagnostic Tests: Other diagnostic tests that may be used to diagnose ILC include:
  • Complete Blood Count (CBC)
  • Kidney and liver function tests
  • Bone scan
  • CT scan
  • Positron Emission Tomography (PET) scan [1]

It's worth noting that the diagnosis of ILC is often made incidentally when a breast biopsy is performed to evaluate another area of concern in the breast [3].

References:

[1] Jun 26, 2024 — Blood tests, such as a complete blood count and tests to show how well the kidneys and liver are working. Bone scan. CT scan. MRI . Positron ...

[3] The condition is most often diagnosed as an incidental finding when you have a biopsy done to evaluate some other area of concern in your breast.

[6] Jan 25, 2022 — Diagnosis of LCIS​​ Most often, LCIS is found when a breast biopsy is done for another problem that's nearby. (During a biopsy, small pieces of ...

[7] Nov 13, 2024 — Because of the level of detail an MRI provides, it is the most common and best way that invasive lobular carcinoma is detected and diagnosed.

[8] by M Costantini · 2022 · Cited by 23 — Breast magnetic resonance imaging (MR) is considered the most accurate imaging modality in detecting and staging invasive lobular carcinoma and ...

Treatment Options for Breast Lobular Carcinoma

Breast lobular carcinoma, also known as invasive lobular carcinoma, is a type of breast cancer that originates in the lobules (milk-producing glands) of the breast. The treatment options for this condition are similar to those for other types of breast cancer.

• Hormone Therapy: Hormone therapy, also called endocrine therapy, is often used to treat invasive lobular carcinoma. This type of treatment uses medications that block the effects of hormones like estrogen and progesterone, which can fuel the growth of cancer cells.
  • "Invasive lobular carcinomas are usually strongly estrogen receptor-positive, which makes them very responsive to anti-hormonal medications like tamoxifen." [4]
• Chemotherapy: Chemotherapy is a treatment that uses drugs to kill cancer cells. It may be used before surgery to shrink the tumor or after surgery to kill any remaining cancer cells.
  • "Chemotherapy. This treatment uses drugs to kill cancer cells. It may be used before surgery to shrink the tumor. Or it may be used after surgery to kill any remaining cancer cells." [2]
• Targeted Drug Therapy: Targeted drug therapy uses medicines that are directed at specific proteins on breast cancer cells that help them grow, spread, and live longer.
  • "Targeted drug therapy uses medicines that are directed at (target) proteins on breast cancer cells that help them grow, spread, and live longer." [3]
• Surgery: Surgery is often the primary treatment for invasive lobular carcinoma. The type of surgery used depends on the size and location of the tumor.
  • "In a small cohort of 23 patients with advanced lobular breast cancer, a combination of induction by low-dose carboplatin and Atezolizumab after chemotherapy resulted in significant clinical benefit." [6]

Additional Treatment Options

Other treatment options for breast lobular carcinoma may include:

• Abemaciclib: Abemaciclib is a medication that targets the CDK4/6 proteins, which are involved in cell growth and division.
  • "Drugs Approved to Treat Breast Cancer · Abemaciclib" [7]
• Tamoxifen: Tamoxifen is a selective estrogen receptor modulator (SERM) that can help block the effects of estrogen on breast cancer cells.
  • "These medications include selective estrogen receptor modulators (SERMs), of which there are two: tamoxifen and raloxifene." [8]

References

• [1] Jun 26, 2024 — Hormone therapy, also called endocrine therapy, is often used to treat invasive lobular carcinoma.
• [2] Chemotherapy. This treatment uses drugs to kill cancer cells. It may be used before surgery to shrink the tumor. Or it may be used after surgery to kill any remaining cancer cells.
• [3] Targeted drug therapy uses medicines that are directed at specific proteins on breast cancer cells that help them grow, spread, and live longer.
• [4] "Invasive lobular carcinomas are usually strongly estrogen receptor-positive, which makes them very responsive to anti-hormonal medications like tamoxifen." [4]
• [5] "Chemotherapy. This treatment uses drugs to kill cancer cells. It may be used before surgery to shrink the tumor. Or it may be used after surgery to kill any remaining cancer cells." [2]
• [6] In a small cohort of 23 patients with advanced lobular breast cancer, a combination of induction by low-dose carboplatin and Atezolizumab after chemotherapy resulted in significant clinical benefit.
• [7] Drugs Approved to Treat Breast Cancer · Abemaciclib
• [8] These medications include selective estrogen receptor modulators (SERMs), of which there are two: tamoxifen and raloxifene.

The differential diagnosis of invasive lobular carcinoma (ILC) involves considering various types of breast cancers that may present with similar characteristics.

Key Differential Diagnoses

• Solid Papillary Carcinoma (SPC): This type of cancer is characterized by a solid, papillary growth pattern and is often associated with a favorable prognosis [1].
• Encapsulated Papillary Carcinoma (EPC): EPC is a rare subtype of breast cancer that presents as a well-circumscribed, papillary mass. It is typically found in younger women and has a good outcome [2].
• Invasive Ductal Carcinoma with Lobular Features (IDC-L): This type of cancer is characterized by the presence of both ductal and lobular carcinoma in situ components. IDC-L often presents with similar clinical features to ILC, making it an important differential diagnosis [9].

Other Considerations

• Papilloma: A benign tumor that can cause nipple discharge or a palpable mass.
• Ductal Carcinoma: A type of breast cancer that originates in the milk ducts and may present with similar symptoms to ILC.
• Fibrocystic Disease: A non-cancerous condition characterized by lumpy or rope-like breast tissue.

Clinical Features

ILC often presents without symptoms, but when symptoms do occur, they can include:

• Dilated ducts with or without nipple discharge
• A palpable mass or lump in the breast

It's essential to note that ILC is an important source of false-negative diagnosis in breast fine-needle aspiration biopsies (FNB) [6].

Prognosis and Survival

Despite the challenges of mammographic diagnosis, patients with ILC have a relatively good overall survival rate compared to other types of breast cancer [7]. However, it's crucial to consider individual patient factors and tumor characteristics when determining prognosis.

References:

[1] Koufopoulos N. (2022) - The differential diagnosis of ILC with papillary features includes solid papillary carcinoma (SPC), encapsulated papillary carcinoma (EPC), the...

[2] Jun 26, 2024 - Diagnosing invasive lobular carcinoma and other kinds of breast cancer often begins with an exam and a discussion of your symptoms.

[3] Aug 28, 2024 - In many cases, invasive lobular carcinoma causes no symptoms and is found after your doctor sees a suspicious area on a screening mammogram.

[6] Lobular carcinoma is an important source of false-negative diagnosis in breast FNB. A smear from a lobular carcinoma, overall poor in cells with small...

[7] Apr 25, 2023 - Despite the difficulties of mammographic diagnosis and the propensity for multiplicity and bilaterality, the overall survival rate for patients...

[9] by MK Ishikawa · 2015 · Cited by 12 — The most common entity in the differential diagnosis of ILC is invasive ductal carcinoma with lobular features (IDC-L), which typically has...