Breast cancer is not a single disease, nor is it confined to one type. Each breast cancer type differs in the tumour localization within the breast, in the cancer cell properties, and in the symptoms and signs of disease. Invasive Ductal Carcinoma (IDC), the breast cancer that starts in the milk ducts and invades surrounding tissues, is the most common breast cancer type (50 – 75% of all cases). Invasive Lobular Carcinoma, where the cancer starts in the milk-producing glands, is the second most common (5 – 15% of all cases). While the other diagnosed breast cancer types are considered rare, some can be very aggressive.
What is Inflammatory Breast Cancer?
Inflammatory breast cancer (IBC) is one of the rare (1 – 5% of all cases), yet very aggressive, breast cancers in which cancer cells block lymph vessels in the skin of the breast. It is referred to as “inflammatory” because the affected breast appears inflamed (red and swollen). IBC grows and spreads fast, and is considered a locally advanced breast cancer – when cancer cells have invaded nearby tissues or lymph nodes.
Warning Signs
In addition to the common breast cancer signs, an IBC has one or more of the following signs:
- Rapid spread of swelling, warmth and redness affecting 1/3 or more of the breast – these symptoms are normally present for less than 6 months
- “Peau d’orange” appearance (ridged or pitted skin)
- Breast enlargement – with or without a lump
- Itching, burning, pain or tenderness in the breast
- Changes to the nipple, where it starts pointing inward (also known as an inverted nipple)
Diagnosis and Treatment
Physical examination and mammography often do not detect a lump in the breast of individuals with IBC. What makes the diagnosis of an IBC even more challenging is that its symptoms closely resemble a breast infection (mastitis). In fact, 35% of IBC cases are metastatic at the time of diagnosis due, at least partly, to a delay in detection. Like any other breast cancer, the earlier the detection occurs, the better the prognosis would be for an IBC patient. Learning about the symptoms of IBC is thus critical for an early detection.
If a patient is suspected to have an IBC, biopsies are performed to assess whether cancer cells have hormone receptors (hormone-positive breast cancer) and/or an elevated amount of HER2 protein (HER2-positive breast cancer). IBC is often hormone-receptor negative and HER2-positive. As IBC is highly metastatic, further testing is performed to evaluate the presence of cancer in local tissues (invasive breast cancer) or distant organs (metastatic breast cancer); these methods include: mammography, ultrasound, Positron Emission Tomography (PET) scan, and Computed Tomography (CT) scan.
Multimodal therapy approaches are chosen to treat IBC: chemotherapy to shrink the tumour, then surgery followed by radiotherapy. Targeted therapy is given if the cancer is HER2-positive, and hormonal therapy is given in cases of hormone-positive tumours.
IBC is more frequently diagnosed in younger women compared to other types of breast cancers. Obesity is a known risk factors for developing IBC. According to the American Cancer Association, IBC is more common among African-American women.
Prognosis and Survival
Up to 65% of people with IBC live at least 5 years, and 35% live at least 10 years from the time of diagnosis. However, it is important to understand that survival rates are analyzed for the large population. IBC prognosis and survival vary between individuals, depending on the characteristics of a patient’s tumour and their medical history.
With the advancement in treatments, survival of individuals with IBC seems to be improving. Ongoing research is continuously uncovering potential effective treatment combinations. Therefore, individuals with IBC are encouraged to participate in a clinical trial where promising therapies are being tested.
For current clinical trials in Quebec, consult the OncoQuebec, Catalis and the Groupe d’Étude en Oncologie du Québec (GEOQ) websites.