What is invasive lobular carcinoma?

Invasive lobular carcinoma (ILC) begins when abnormal cells form in your breast and spread to other parts of your breast tissue. ILC is the second most common type of breast cancer, making up about 10% of all breast cancer cases. The condition is sometimes called infiltrating lobular carcinoma.

What's the difference between invasive lobular carcinoma and invasive ductal carcinoma?

Invasive lobular carcinoma tends to grow in a single-file pattern of cells compared to invasive ductal carcinoma (IDC), which more commonly forms a mass or lump. ILC can be detected under the microscope by the lack of a specific protein called E-cadherin.

Who does invasive lobular carcinoma affect?

Women who are 55 or over are most likely to develop invasive lobular carcinoma. Men can develop ILC, too, though it’s rare. Transwomen have a higher risk of developing breast cancer than cisgender men. Conversely, transmen have a lower risk compared to cisgender women.

Unlike invasive ductal carcinoma (IDC), invasive lobular carcinoma usually occurs later in life. Many people are in their early 60s at the time of their diagnosis.

How common is invasive lobular carcinoma?

About 10% of all breast cancers are invasive lobular carcinomas. It’s considered the second most common type of breast cancer, just after IDC. ILC is more common in women than men. It makes up about 2% of male breast cancers.

Is invasive lobular carcinoma fast-growing?

No. Invasive lobular carcinoma is usually slow-growing.

What are the stages of invasive lobular carcinoma?

Invasive lobular carcinoma is divided into four stages. Staging is based on several factors, including the size of the tumor, where it’s located and how far it has spread:

• Stage 1: The tumor is up to 2 centimeters (cm) across and may have spread to nearby lymph nodes.
• Stage 2: At this stage, the tumor may be about 2 cm across and the cancer has spread to nearby lymph nodes. Or, the tumor has grown up to 5 cm across and the cancer hasn’t spread to nearby lymph nodes.
• Stage 3: The cancer may have spread to lymph nodes, but hasn’t spread to distant sites like other organs in your body. In some cases, the cancer may have spread into your chest wall.
• Stage 4: The cancer may or may not have spread to nearby lymph nodes. The cancer has spread to distant lymph nodes or organs, which may include your liver, lungs, bone or brain. Stage 4 is also referred to as metastatic breast cancer.

What are the symptoms of invasive lobular carcinoma?

Like most breast cancers, invasive lobular carcinoma may not cause any symptoms in the early stages. However, some people may notice these warning signs:

• An area of swelling or fullness in your breast.
• A change in the appearance or texture of your breast skin.
• Dimpling of your breast.
• Thickening of your breast skin.
• Inverted nipple.
• Breast pain.
• A lump near your armpit.
• Nipple discharge (that isn’t breast milk).

Unlike other types of breast cancer, ILC may not result in an obvious lump or bump in your breast. The affected area may feel different from the surrounding tissue. These symptoms are also similar to symptoms of other serious conditions, such as inflammatory breast cancer (IBC). Therefore, you should contact your healthcare provider immediately if you notice anything unusual.

What causes invasive lobular carcinoma?

Experts know that ILC occurs when cells in your breast develop mutations in their DNA. But they aren’t exactly sure what causes those mutations to occur. There are factors that could increase your risk for invasive lobular carcinoma, including:

• Age. Most people who are diagnosed with invasive lobular carcinoma are over the age of 55.
• Sex. Women are more likely to develop ILC.
• Hormone therapy. Women who use hormone therapy after menopause may have an increased risk of invasive lobular carcinoma.
• Genetic factors. Certain inherited genes could play a role in whether or not you get breast cancer. A rare condition called hereditary diffuse gastric cancer syndrome can increase your risk for both invasive lobular carcinoma and stomach cancer.

How does invasive lobular carcinoma spread?

The term “invasive” means that the cancer started in the lobules or ducts of the breast but spread to surrounding breast tissue. Eventually, the cancer can also spread to lymph nodes, organs and other areas throughout your body.

Where does invasive lobular carcinoma spread to?

ILC first spreads from your breast tissue to nearby lymph nodes. After that, it most commonly spreads to your liver, bone, lungs or brain.

How is invasive lobular carcinoma diagnosed?

In most cases, invasive lobular carcinoma is detected during a routine mammogram or by physical exam. During this exam, your healthcare provider will feel for lumps, bumps, skin thickening or other abnormalities in your breast. They may also order other tests, including:

• Ultrasound. This imaging test uses sound waves to capture pictures of your breast tissue. Ultrasound may be used as a standalone test or in combination with mammography.
• Magnetic resonance imaging (MRI). Your healthcare provider may request an MRI, which uses radio waves and magnets to take detailed pictures inside your body.
• Biopsy. In order to confirm that the cancer is present, your healthcare provider may take a small sample of breast tissue and send it to a pathology lab for analysis.

How is invasive lobular carcinoma treated?

There are two main categories of ILC treatment — local and systemic. Local treatments target the tumor and the surrounding areas, while systemic treatments travel through your body to kill any cancer cells that have spread throughout it.

Local treatments for invasive lobular carcinoma

Local treatments include:

• Surgery. This is usually the first line of treatment recommended for invasive lobular carcinoma. A lumpectomy or mastectomy is performed to remove the tumor. During the procedure, your surgeon will also check to see if the cancer has spread to your lymph nodes.
• Radiation therapy. This treatment focuses high-energy radiation rays at your breast, underarm regions and surrounding areas. Radiation therapy is often recommended after surgery to destroy any remaining cancer cells.

Systemic treatments for invasive lobular carcinoma

Systemic treatments include:

• 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.
• Targeted drug therapy. This type of treatment targets certain characteristics of cancer cells in order to destroy them. Targeted therapy is less likely than chemotherapy to destroy healthy cells.
• Anti-hormone therapy. If the cancer tests positive for hormone receptors, which most ILCs do, then anti-hormone therapy may be a good option. This approach lowers the amount of estrogen in your body. As a result, it blocks or reduces the growth of breast cancer cells.

Are there side effects of invasive lobular carcinoma treatment?

As with any cancer treatment, people who undergo treatment for invasive lobular carcinoma may experience some side effects. These side effects depend on the type of treatment you undergo, how advanced your cancer is, your body’s healing capacity and other factors.

People who undergo surgery for invasive lobular carcinoma may develop infections, blood clots, allergies to anesthesia or other complications. Radiation therapy is often associated with fatigue, nausea and skin irritation.

People who undergo chemotherapy may develop several side effects, including:

• Cancer fatigue.
• Hair loss.
• Skin changes.
• Fever.
• Headaches.
• Anemia.
• Diarrhea.
• Constipation.
• Fertility problems.

For people receiving anti-hormone therapy, the most common side effects are hot flashes, joint pain, weight changes, mood changes, vaginal dryness or discharge, and a decrease in sexual desire.

How long does it take to recover from invasive lobular carcinoma treatment?

Healing times can vary for each individual. If you’ve had surgery, recovery usually takes about two to four weeks. Chemotherapy, radiation therapy and targeted therapy may take several weeks to several months depending on your specific situation. Ask your healthcare provider what to expect in terms of recovery.

How can I reduce my risk for invasive lobular carcinoma?

Although you can’t prevent invasive lobular carcinoma altogether, there are things you can do to reduce your risk. For example:

• Eat a healthy diet.
• Avoid smoking.
• Drink alcohol in moderation.
• Stay at a healthy weight.
• Exercise regularly.

What can I expect if I have invasive lobular carcinoma?

Fortunately, ILC is a slow-growing cancer, so there is the opportunity to catch it in the early stages when treatment is most successful. Invasive lobular carcinoma prognosis depends on several factors, including the size of the tumor, its location and whether or not it has spread. If you’ve recently been diagnosed with ILC, talk with your healthcare provider about treatment options as soon as possible.

Can invasive lobular carcinoma be cured?

Yes. Invasive lobular carcinoma can be cured when caught and treated early.

What is the survival rate for invasive lobular carcinoma?

The five-year survival rate for invasive lobular carcinoma is high compared to other types of cancer — nearly 100% when treated early. If the cancer has spread to nearby tissues, the five-year survival rate is about 93%. If it has metastasized to other areas of your body, the five-year survival rate is 22%.

It’s important to note that survival rates can’t tell you how long you’ll live. These estimates are based on people who have had invasive lobular carcinoma in the past. To learn more about your unique case, talk to your healthcare provider.

When should I see my healthcare provider regarding invasive lobular carcinoma?

Any time you notice any sudden or unusual changes in your breast tissue, you should schedule a consultation with your healthcare provider. They can run tests to determine if you have breast cancer. If you’re already undergoing treatment for ILC, call your healthcare provider if you develop any worrisome symptoms, such as chest pain, confusion, chills, high fever, shortness of breath (dyspnea) bone pain or abdominal pain.

What questions should I ask my healthcare provider?

If you’ve been diagnosed with invasive lobular carcinoma, you’ll want to gather as much information as possible. Here are some questions you can ask your healthcare provider:

• What stage is my invasive lobular carcinoma?
• How far has it spread?
• What are my treatment options?
• How long will my treatment take?
• Will I be able to work while undergoing cancer treatment?
• What is my outlook?

When should I see my healthcare provider regarding invasive lobular carcinoma?

Any time you notice any sudden or unusual changes in your breast tissue, you should schedule a consultation with your healthcare provider. They can run tests to determine if you have breast cancer. If you’re already undergoing treatment for invasive lobular carcinoma, call your provider if you develop any worrisome symptoms, such as chest pain, confusion, chills, high fever, shortness of breath (dyspnea) bone pain or abdominal pain.

What questions should I ask my healthcare provider?

If you’ve been diagnosed with invasive lobular carcinoma, you’ll want to gather as much information as possible. Here are some questions you can ask your healthcare provider:

• What stage is my invasive lobular carcinoma?
• How far has it spread?
• What are my treatment options?
• How long will my treatment take?
• Will I be able to work while undergoing cancer treatment?
• What is my outlook?