Inflammatory breast cancer is a rare and particularly aggressive form of breast cancer that forms around 1% of all breast cancers. Inflammatory breast cancer has a different pathology to other forms of breast cancer as well as a different symptom profile, prognosis and treatment approach.
Inflammation is the body's response to harmful stimuli, and involves the accumulation of white blood cells at the site of infection, damage or irritation. Inflammation is typically characterized by redness, heat, swelling and pain at such sites.
Inflammatory breast cancer
In inflammatory breast cancer, the breast shows symptoms of inflammation. The breast may be swollen, red, warm, itchy and painful. Other symptoms include a thickening or pitting of the skin, one breast larger than the other and nipple changes. In inflammatory breast cancer, cancer cells grow along the inside of the lymph vessels in the breast causing them to become blocked. These obstructed lymph vessels are then unable to drain fluid or filter bacteria and waste substances effectively, which causes swelling and the symptoms of inflammation.
As the cancer cells grow along the inside of the lymph vessels rather than forming a lump, this form of breast cancer is more difficult to detect using routine screening by mammogram. In addition, the symptoms are easily confused with those of breast infection and inflammation (mastitis), further complicating the diagnosis process for inflammatory breast cancer.
Age and other factors in inflammatory breast cancer
Inflammatory breast cancer generally occurs at a younger age than other, more common forms of breast cancer. The average age for developing inflammatory breast cancer is 52 years compared with 57 years for the other forms. Other factors that influence the risk for inflammatory breast cancer include ethnicity and weight. African-American women are at an increased risk for the condition over white women and overweight or obese individuals are at an increased risk compared with normal weight individuals.
Men can also develop inflammatory breast cancer, but this is rare.