Symptoms: Aromatase Inhibitor Induced Arthralgias

Recent clinical trials have demonstrated that aromatase inhibitors (AIs) are slightly more effective than tamoxifen at reducing breast cancer recurrences. However, breast cancer patients receiving AIs have a higher incidence of musculoskeletal symptoms, particularly joint pain and stiffness. Musculoskeletal pain and stiffness can lead to noncompliance and increased utilization of health care resources. There is a suggestion that the syndrome is the result of estrogen deprivation and may share components with autoimmune diseases such as Sjögren's syndrome. Several factors may increase the likelihood of developing AI arthralgia, such as prior chemotherapy, prior hormone replacement therapy, and increased weight; there are inconsistencies with regard to the data on genetic predispositions to this syndrome. While several studies have been done to evaluate interventions to treat or prevent AI arthralgia, no clear treatment has emerged as being particularly beneficial. Much of the research has been limited by small sample size, difficulty blinding patients to placebo, inconsistent definitions of the syndrome, multiple patient reported outcomes, lack of objective outcome measures and heterogeneous patient populations. We are at the early stages of research in characterizing, understanding etiology, preventing and treating AI arthralgias; however much work is being done in this area which, hopefully, will ultimately improve the lives of women with breast cancer.