Inflammatory breast cancer (IBC), which is characterized by involvement of the skin, is rare, accounting for approximately 3% of breast cancers. Inflammatory breast cancer is more likely to be HER2+ than ductal or lobular breast cancer, the most common types of invasive breast cancer.
Patients with inflammatory breast cancer tend to be younger than patients with other types of breast cancer (the majority are 40 to 59 years old at diagnosis) and they are also somewhat more likely to be African American or pregnant at the time of diagnosis.
Low socioeconomic status is associated with increased risk of inflammatory breast cancer even after adjusting for age and race/ethnicity. Women with inflammatory breast cancer are more likely to develop contralateral breast cancer (cancer in the initially non-cancerous breast) than women with comparably staged non-inflammatory breast cancer.
Onset of inflammatory breast cancer can be rapid
Women with IBC typically present with a history of less than six months of rapid breast enlargement and redness of the skin. Other possible symptoms include breast or underarm pain, a sensation of heat in the breast, skin ridging, and an orange peel-like appearance of the overlying skin. There may or may not be an underlying mass that can be felt by hand. Women with inflammatory breast cancer often have the experience of being prescribed a course of antibiotics for breast infection.
Survival rates vary and have been improving
The prognosis for inflammatory breast cancer patients is not favorable—the disease accounts for approximately 10% of breast cancer-specific deaths in the U.S. However, survival rates have shown some improvement over time. Approximately one third of women with inflammatory breast cancer present with distant metastases. Surgery to remove the tumor has been shown to have a survival benefit, as has radiotherapy. Because this cancer is rare and difficult to treat, it is important for inflammatory breast cancer patients to obtain treatment at a breast cancer center with experience in its management. Time is of the essence in this type of breast cancer - treatment should be swift and aggressive.
One clinical trial with a median follow-up period of 20 years demonstrated that relatively good survival and local control can be achieved in inflammatory breast cancer patients with an aggressive schedule of alternating chemotherapy and radiation treatments. The metastases-free survival rates were 45% (five-year), 30% (10-year), and 20% (20-year). Recent research suggests that statins (used to lower cholesterol), can improve progression-free survival in women with inflammatory breast cancer.
Immune system processes are distorted in inflammatory breast cancer
Women with inflammatory breast cancer have been shown to have significant reductions in immune cells responsible for adaptive immunity. Furthermore, stage IV inflammatory breast cancer patients are more immunocompromised than non-metastatic inflammatory breast cancer patients. Inflammatory conditions created by cells of the innate immune system, including natural killer and dendritic cells, appear to promote metastasis in inflammatory breast cancer. Immune activation (as evidenced by dendritic cell pro-inflammatory cytokine production, expression of costimulatory molecules, and increased natural killer counts) is associated with poor prognosis.
Breast cancer virus may contribute to inflammatory breast cancer
Retroviral sequences similar to mouse mammary tumor virus have been found in 40% of nonfamilial breast cancers in U.S. women and an even higher proportion in cases of inflammatory breast cancer and pregnancy-related breast cancer. Mammary tumor virus sequences have not been detected in normal breast tissue or other tumors. Inflammatory breast cancer in U.S. women has been found to have a higher incidence of viral sequences (71%) than other sporadic breast cancers. However, causality has not been proven and research is at an early stage — treatments based on these findings are nonexistent.
Please also see our article on breast cancer diet for IBC. Inflammatory breast cancer patients and survivors should also refer to our articles concerning breast cancer subtypes (e.g., triple negative, ER+/PR+, HER2 overexpressing (HER2+)).
Below are links to recent studies on this topic. For a more complete list of studies, please click on IBC.