Invasive Lobular Carcinoma

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Overview

Invasive Lobular Carcinoma (ILC) is a type of breast cancer that originates in the breast lobules, which are the glands responsible for milk production. It falls under the histological classification of carcinoma, a category that encompasses malignant tumors derived from epithelial cells. ILC is the second most common type of invasive breast cancer, following Invasive Ductal Carcinoma (IDC).

Symptoms

ILC can be more challenging to detect than other forms of breast cancer due to its tendency to spread in a single-file pattern through the stroma of the breast tissue, rather than forming a distinct lump. Symptoms may include:

• Thickening or swelling in part of the breast
• Change in the size, shape, or appearance of the breast
• Changes to the skin over the breast, such as dimpling
• A newly inverted nipple
• Redness or pitting of the skin over the breast, similar to the texture of an orange
• Unexplained pain in the breast or nipple

Surgical Options

1. Lumpectomy: Removal of the tumor and a small margin of surrounding tissue. This is often followed by radiation therapy.

2. Mastectomy: Removal of the entire breast. This may be recommended if the cancer is widespread or if the patient has a high risk of recurrence.

Radiation Therapy

Radiation is commonly used after surgery to destroy any remaining cancer cells. It is an established treatment that has been in use for decades, with continuous advancements in precision and safety.

Chemotherapy

Chemotherapy may be recommended, especially if the cancer is larger than a certain size or has spread to lymph nodes. This treatment uses drugs to kill cancer cells or stop them from growing.

Hormonal Therapy

Since many ILC tumors are hormone receptor-positive, hormonal therapy is effective. This can involve:

• Tamoxifen: Used for premenopausal and postmenopausal women.
• Aromatase Inhibitors: Such as anastrozole, letrozole, or exemestane, which are used primarily in postmenopausal women.

Targeted Therapy

HER2-targeted therapies, like trastuzumab (Herceptin), may be used if the cancer cells overexpress the HER2 protein.

Immunotherapy

Research into immunotherapy for breast cancer is ongoing. This treatment harnesses the body's immune system to fight cancer. As of 2023, certain immunotherapy treatments are approved for other types of breast cancer but are still experimental for ILC.

PARP Inhibitors

Drugs like olaparib, which target the DNA repair pathways in cancer cells, are being investigated for their efficacy in treating ILC, especially in patients with BRCA mutations.

CDK4/6 Inhibitors

Drugs that inhibit proteins involved in cell division, such as palbociclib, ribociclib, and abemaciclib, are being explored in combination with hormonal therapies for enhanced effectiveness.

Side Effects of Treatments

Surgery

• Infection
• Pain and tenderness
• Changes in breast shape
• Lymphedema (swelling due to lymph node removal)

Radiation

• Fatigue
• Skin irritation
• Swelling and heaviness in the breast

Chemotherapy

• Nausea and vomiting
• Hair loss
• Increased risk of infection
• Fatigue

Hormonal Therapy

• Hot flashes
• Joint pain
• Risk of blood clots
• Increased risk of osteoporosis

Targeted Therapy

• Heart problems (with HER2-targeted therapy)
• Diarrhea
• Fatigue

Modernity of Treatments

• Surgical and Radiation Therapies: These have been standardized over several decades, with continuous improvements in techniques.
• Chemotherapy and Hormonal Therapies: Widely used since the latter half of the 20th century, with ongoing refinements.
• Targeted Therapies: Became more prominent in the early 2000s, with new drugs continually being developed.
• Immunotherapy and CDK4/6 Inhibitors: Represent some of the newest frontiers, with research and clinical trials ramping up significantly since the 2010s.

For the most up-to-date information, patients should consult healthcare professionals and consider clinical trials as potential avenues for treatment.