A Comprehensive Overview of Inflammatory Breast Cancer

Inflammatory Breast Cancer (IBC) is a rare form of breast cancer where the cancer cells block the lymph channels in the breast, causing the breast to look red and “inflamed”, thus the name inflammatory breast cancer.

Approximately 1% to 5% of all breast cancers diagnosed in the United States are IBCs and most of them are invasive ductal carcinomas. IBC is an aggressive cancer that progresses rapidly, within weeks or months, which makes it difficult to detect before metastasis. In approximately 30% of IBC cases, it has already metastasized to distant parts of the body. As compared to other breast cancer types, IBC has the following characteristics:

• Tend to be diagnosed at a younger age
• More common in African American women
• More common in obese women
• Tend to be hormone receptor negative (these cancers cannot be treated with hormone therapy)

While IBC may have a few similar symptoms to other more common forms of breast cancer, there are certain symptoms that are specifically associated with IBC. Typical symptoms of IBC include:

• Breast feeling hard and firm
• Red breast skin
• Swollen breasts
• Breasts feel hot to the touch
• Thickening of the breast skin
• Pitted skin (like an orange peel)
• Nipple discharge
• Inverted nipple
• Breast lump (while breast lumps are a rare symptom of IBC, it may still be present in some cases)

As IBC is quite an aggressive form of breast cancer, symptoms may appear quite suddenly. However, these symptoms may not necessarily mean one has cancer. They may also be symptoms of other diseases or conditions, such as mastitis (breast infection), especially during pregnancy or breastfeeding. As such, alerting a healthcare professional to such symptoms is important to determine and resolve any conditions that may be causing these symptoms.

IBC is particularly difficult to diagnose due to a few reasons:

• Most IBCs do not result in breast lumps, which means that breast cancer screening methods such as screening mammograms may not be able to identify IBC.
• IBC is a fast-progressing cancer. It may progress rapidly between screenings, which reduces the chances of early diagnosis.
• IBC has symptoms similar to other breast diseases or conditions. For example, swelling of the breast, together with redness, is also a symptom of mastitis—a type of breast infection in pregnant or breastfeeding women. As such, IBC may be initially misdiagnosed as another condition that leads to delays in diagnosis and treatment.
• IBC is a rare cancer. As it is rare, it may be diagnosed and treated as a more common condition before IBC is considered. For example, symptoms of IBC may be treated as a breast infection and treated with antibiotics for a period of time, which may allow the cancer to further progress.

To reduce the occurrence of delays in diagnosis and misdiagnoses, a panel of leading IBC experts has formed a consensus on the minimum requirements to accurately diagnose IBC, supported by pathological confirmation, which includes:

• The sudden appearance of redness, swelling, pitted skin, and abnormal breast warmth, with or without the presence of lumps
• The presence of the above symptoms for less than 6 months
• Area of redness that covers at least one-third of the breast
• Initial biopsy samples from the affected breast that show invasive carcinoma

If IBC is suspected, one or more of the following imaging tests may be done:

• Diagnostic mammogram
• Breast ultrasound of nearby lymph nodes
• Breast MRI
• PET scan, CT scan, or bone scan to check if cancer has spread to other parts of the body

Photos of the breast may also be taken to monitor swelling and appearance to track treatment response. A biopsy is also needed to confirm the diagnosis of IBC. A small tissue of breast skin or lump is taken from a punch biopsy. The sample is examined in a laboratory by a pathologist and the report will indicate if breast cancer cells are present. If they are present, further tests are done to determine if certain proteins or hormone receptors are present, which may help in determining a treatment plan.

Due to the aggressiveness and fast-growing nature of IBC, a multimodal approach that consists of the following treatment methods is normally used:

• Chemotherapy

As IBC is always a stage III cancer or above at diagnosis, chemotherapy is often used at the start to shrink the tumor before any other treatment. This kind of chemotherapy is called neoadjuvant chemotherapy. Adjuvant chemotherapy—chemotherapy done after surgery may also be done in some cases to get rid of remaining cancer cells in the chest or in distant parts of the body if the body has metastasized.

• Targeted therapy

For IBCs that are HER2 positive.

• Hormone therapy

For IBCs that are hormone receptor-positive.

• Surgery

Due to the stage of cancer at diagnosis for IBC, breast-conserving surgery is often not considered as a treatment option. A modified radical mastectomy is usually the recommended surgery for IBC. In a modified radical mastectomy, the entire affected breast, most or all of the lymph nodes under the adjacent arm, as well as the lining over the underlying chest wall, are removed. In some cases, parts of the chest muscles are removed as well.

• Radiation therapy

The five-year relative survival rate for all cases of IBC is 40%, while that of the IBC of the specific stages are as follows:

It is important to note that relative survival rates are based on the average experience of all women and do not dictate the experience or survival outcomes of each individual, as there are many factors that may affect one’s outcome. Additionally, the data that these rates are based on also include data from many years ago when diagnostic technology and treatments were not as advanced.