Invasive Lobular Carcinoma (ILC)

Overview

Breast cancer is cancer that begins in the breast tissue. Invasive lobular carcinoma – or ILC – is a type of breast cancer that starts in the milk-producing lobules of the breast and then spreads to other areas. ILC is the second most common type of breast cancer (after invasive ductal carcinoma ) – roughly 10 percent of all invasive breast cancers are ILC cases.

Invasive lobular carcinoma causes

Invasive lobular carcinoma is caused by mutations (changes) to the DNA of the cells of the lobule of the breast.

Invasive lobular carcinoma risk factors

The following factors may increase your risk for developing ILC:

• Being older than 55
• Having undergone hormone replacement therapy for menopause

Invasive lobular carcinoma symptoms

In its early stages, many women with ILC will not experience any symptoms. When they do occur, signs and symptoms of ILC may include:

• Area of swelling or fullness
• Change in the texture of the breast skin, such as scaliness or dimpling
• Lump in the underarm area that can be felt
• Nipple discharge other than breast milk
• Nipple turned inward
• Pain in the breast or nipple
• Skin irritation
• Thickening or hardening of the breast that can be felt from the outside

Invasive lobular carcinoma diagnosis

Your oncologist may use one or more of the following tests to diagnose this condition:

• Physical exam – your doctor will perform a complete physical exam, including asking questions about your health history, symptoms and related risk factors.
• Computerized tomography (CT) scan – this type of imaging test provides a 3D image of the inside of the body that your doctor can use to determine if there is any cancer present.
• Biopsy – in this test, your doctor removes a biopsy (small tissue sample) from the suspicious area. This sample is sent to the laboratory, where a specialist closely checks the biopsy for abnormalities.
• Magnetic resonance imaging (MRI) – this type of imaging test uses high-powered magnets to create detailed images of the inside of your body. Your doctor can closely examine these images to look for any areas that could indicate cancer.
• Mammogram – this specialized type of breast X-ray captures images of the inside of the breast. These images allow your doctor to look for any areas of irregularity. 
• Ultrasound – this type of imaging test uses sound waves to create detailed images of the inside of your body. Your doctor can closely examine these images to look for any areas that could indicate cancer.

Invasive lobular carcinoma treatment

Depending on your personal health history, the extent of your invasive lobular carcinoma and other factors, your oncologist may recommend one or more of the following treatment options:

• Surgery – in most cases, your doctor will recommend a surgical procedure to remove the cancerous area. Your surgeon will work to preserve as much surrounding healthy tissue as possible. In some cases, you may opt to undergo reconstructive surgery following surgery to treat breast cancer.
• Chemotherapy – you may need to undergo chemotherapy to destroy any cancerous cells that couldn’t be removed surgically. During this treatment, medication is used to destroy cancerous cells. Chemotherapy can be taken via an oral (by mouth) pill or intravenously (through a vein).
• Hormone therapy – if you have hormone receptor-positive breast cancer, your oncologist may recommend you undergo hormone therapy for estrogen and progesterone.
• Radiation therapy – this treatment uses high-powered energy beams to destroy cancerous cells. You may need to undergo radiation therapy to destroy any cancerous cells that couldn’t be removed surgically.
• Targeted therapy – this treatment focuses on the molecular changes that make cancer cells grow and spread. These therapies are less likely than chemotherapy to harm healthy cells and may have fewer side effects. 

When should I seek care?

If you experience any of these symptoms, start by voicing your concerns and symptoms to your primary care provider. From there, your doctor may suggest seeing an oncologist for more specialized treatment.