Treatment for and clinical characteristics of granulomatous mastitis.

Objective: To describe the clinical and paraclinical characteristics of idiopathic granulomatous mastitis, the management of our patients, and review the literature on this topic.

Methods: Patients referred to our clinic with a presumptive diagnosis of infectious mastitis were only included in the study if they had histopathologic confirmation of granulomatous mastitis. A systemic or infectious etiology was excluded by the testing of tissues and fluids by staining, culture, and polymerase chain reaction methods. Those patients with no reported etiology were categorized as idiopathic granulomatous mastitis and treated with antiinflammatory drugs. All were monitored for signs of recurrence.

Results: All 22 patients with a final diagnosis of idiopathic granulomatous mastitis were women with a mean age (± standard deviation) of 32.8 ± 6.2 years. Initial treatment with a prednisone regimen was given in 15 (68.2%) patients, prednisone plus methotrexate (MTX) in six (27.3%), and MTX alone in one (4.5%). Among the total of 22 patients with idiopathic granulomatous mastitis, 12 (54.5%) received MTX either as an initial treatment or as an alternative regimen. Of the 22 patients, three (13.6%) had disease recurrence and four (18.2%) experienced adverse drug reactions. Sixteen (72.7%) patients discontinued the initial treatment regimen with acceptable control of disease activity and without recurrence or adverse drug reactions during the follow-up period.

Conclusion: Idiopathic granulomatous mastitis is a distinct benign breast condition of unknown etiology but several triggers are suspected, including inflammatory, infectious, and hormonal factors. Corticosteroids and MTX, with or without surgery, are the treatment of choice in these patients.