What is invasive lobular carcinoma?

Invasive lobular carcinoma is a cancer that forms in the breasts. Specifically, the cancer forms in the lobules, where milk is produced. If a cancer is invasive, it means cancer cells have spread to another part of the body. With invasive lobular carcinoma, cancerous cells might spread to other parts of breast tissue, for example.

This is the second most common form of breast cancer, behind invasive ductal carcinoma, and affects about 10% of people with invasive breast cancer.

Common related conditions
Breast Cancer Invasive Ductal Carcinoma (IDC)

Causes of invasive lobular carcinoma

The causes of this disease are unknown. The cancer forms when cells in the milk-producing glands mutate, or change. This mutation causes cancerous cells to grow rapidly and spread.

Risk factors for invasive lobular carcinoma

  • Gender — if you're a woman, you're more likely than men to develop breast cancer.
  • Age — invasive lobular carcinoma typically affects women in their 60's.
  • Hormone use — if you used hormones to treat menopause, you're at a higher risk for this invasive form of breast cancer.

Symptoms of invasive lobular carcinoma

In the beginning, you may not notice symptoms. As it grows, subtle symptoms may occur. These symptoms are quite different than those of other breast cancers. This form of cancer doesn't form a lump in the breast. Instead, ducts harden, which may cause:

  • A thickening of breast tissue
  • An area of fullness or swelling
  • A thickening of the skin around the breast
  • An inverted nipple

If you have any of these symptoms, make an appointment with your doctor.

Diagnosis of invasive lobular carcinoma

Since this disease doesn't form a lump, it's sometimes hard to see on a mammogram. If you find a suspicious area, your doctor will likely order a biopsy to inspect the cells in that part of your breast.

A biopsy uses a needle to draw out cells from the area so they can be looked at under a microscope. From this sample, your doctor can tell if you have invasive lobular carcinoma and how aggressive it is.

Your doctor will likely order a few other tests to see if the cancer has spread. These tests might include a CT scan, MRI, an x-ray or a bone scan. All of these tests involve taking pictures of your body with different instruments to see if cancerous cells are in other parts of your body.

Treatments for invasive lobular carcinoma

Treatment options depend on how far the cancer has progressed and your overall health.

  • Surgery — your doctor may suggest a lumpectomy, in which a surgeon removes infected tissue, or a mastectomy, in which a surgeon removes an entire breast.
  • Chemotherapy — your doctor may suggest chemotherapy alongside surgery; chemotherapy uses a combination of medications, orally or through an IV, to kill cancer cells.
  • Radiation — following surgery, you may need radiation, which uses strong beams of energy directed at the targeted area of your breast to kill cancer cells.
  • Hormone therapy — in some cases, invasive lobular carcinoma is responsive to hormone therapy, which blocks hormones in your body from stimulating the cancer cells inside.

Your doctor can test the cells in your breast to see if this treatment is an option for you.

Recovery from invasive lobular carcinoma

Research shows the 5-year survival rate is 83%.

Recovering from an invasive breast cancer diagnosis and treatment is a challenge. To help cope, follow these tips:

  • Know your options — education is valuable, learn everything you can about your cancer and what your options are.
  • Rely on family — lean on your family and friends for support. Talk with them about your condition and recovery process.
  • Connect with other survivors — talking with others who have experienced invasive lobular carcinoma can be very helpful.

The right medical and emotional support can provide a lot of help.

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