Invasive Lobular Carcinoma

Invasive lobular carcinoma is a type of breast cancer. It is the second most common type of breast cancer. It begins in the lobules (milk-producing glands) of the breast as is found in both the breasts. So, it is also called as lobular breast cancer. Nearly 10% of people are affected with invasive lobular cancer. It is also found in males in very rare cases.

The word invasive infers that the cancer spreads from the place of its origin. The cancer cells of the breast lobules can spread easily the other tissues, lymph nodes and other parts of the body very rapidly. Invasive lobular carcinoma (ILC) can also make up the most common type of breast cancer such as invasive ductal carcinoma (IDC). ILC can be diagnosed at any age, but it is most common in women above 60 years. It is mostly seen in women who are on hormone therapy during or after menopause.

The exact cause of ILC is unknown. It begins when the milk-producing glands develop mutations in their DNA. These mutations lead to inability in cell growth which results in uncontrolled cell division and growth. The ILC can spread to surrounding breast tissue in an aggressive manner.

ILC does not forms distinctive lumps, rather the affected area can be thicker and give a feel of fullness. The symptoms are not observed in the early stages; they are only visible or felt in the later stages. Some of the symptoms include:

  • Nipple pain
  • Inverted nipple
  • Redness and pain in the breast
  • Thickening of part of the breast
  • Nipple discharge other than breast milk
  • A feeling of fullness and swelling in the breast
  • A change in the texture of the skin over the breast (hardening, flattening and dimpling)

The diagnosis of ILC involves

  • Mammogram: Mammogram is an X-ray of the breast. It is used to diagnose ILC, but in some cases mammogram is not sufficient to confirm the diagnosis as ILC may not be detected clearly.
  • Chest X-Ray: It is performed to take detailed images of the chest, to check the spread of ILC. Radiation is used in low doses to create images.
  • CT scan: Powerful X-ray scan is performed to take images of the whole body to check the spread of the ILC.
  • PET scan: It is performed along with CT scan to check the spread of ILC in lymph nodes and other areas of the body.
  • Ultrasound: sound waves are used to create an image of the breast.
  • Magnetic Resonance Imaging (MRI): MRI uses strong magnetic field to create images of the breast. It is more efficient and accurate to diagnose and conclude ILC. The extent of spread of cancer is also detected by MRI.
  • Biopsy: A sample of the breast tissue will be taken for the laboratory testing of the growth of the cancerous cells. It is usually done by a needle. Tissue or fluid from the breast is withdrawn by the needle. Sometimes a surgery may also be required to remove the sample tissue from the suspected breast area.

After the confirmation of diagnosis, the doctor does the staging of the cancer. The higher the numbering of the stage, the critical the stage is. Sometimes, doctors may suggest some additional tests like blood tests to confirm the staging. Usually, the staging starts from 0 to IV. Stage O is indicated a noninvasive and stage IV is indicated as metastatic. It indicates that the cancer has spread to other parts of the body.

The treatment for ILC depends on the stage, and aggressiveness of the cancer. The treatment includes surgery and additional therapies such as chemotherapy, radiation therapy, and hormone replacement therapy.

There are different surgical techniques that include:

Lumpectomy: In this type, a wide local excision is done to remove the cancer part and a small portion of the healthy tissue. The surrounding healthy tissue is removed to make sure all the cancer tissue is removed from the body. This procedure allows retaining most of the breast tissue in the place.

Mastectomy: It involves the removal of whole breast tissue. It includes the removal of lobules, ducts, fatty tissue, skin, nipple, and areola. Radical mastectomy is also suggested sometimes based on the spread of ILC; it involves the removal of whole breast tissue including lymph nodes in the armpit.

Axillary Lymph Node Dissection: If ILC is diagnosed in the sentinel node, then the additional lymph nodes in the armpit are removed by dissection.

Identification of the spread of cancer to the lymph nodes is essential to determine the need of adjuvant therapies.

Chemotherapy: It is used to destroy the cancer cells. It can be an oral or an intravenous treatment or both. It involves a combination of two or more drugs. It is suggested to remove any cancer cells that are left over after surgery. It is also suggested before surgery to shrink the cancer cells.

Radiation Therapy: High-energy X-ray beams are used to kill the cancer cells. It is usually suggested after lumpectomy or mastectomy.

Hormone Therapy: Most of the invasive lobular carcinomas are hormone receptor sensitive. The hormone therapy can block the body from producing hormones that help the cancer cells to grow. One of the hormone therapy drugs is selective estrogen receptor modulators (SERMs) which work by blocking estrogen that stimulate the breast tissue. An example for SERM is tamoxifen. Another example is aromatase inhibitors, such as anastrozole, letrozole, and exemestane, which can be used for women who are in menopause or later menopause.