Granulomatous mastitis: a 10 year experience from a large inner city county hospital

Background: Granulomatous mastitis (GM) is a rare, chronic, inflammatory condition of the breast with unknown etiology that affects women of child-bearing age. It can be mistaken radiographically and clinically for breast cancer and due to its rarity can cause a delay in establishing a definitive diagnosis and subsequent initiation of treatment. Furthermore, GM has a progressive clinical course with multiple recurrences. To date, there is no universally accepted treatment for GM. The goal of this study is to review the experience with granulomatous mastitis at a large inner-city public hospital over a 10-y period.

Methods: A retrospective review of a prospectively maintained institutional database was queried for all patients with a histopathologic diagnosis of GM between July 1, 2000 and July 1, 2010. A separate database was created for these patients, and data was collected from electronic medical records and paper charts. Demographic, clinical, and outcomes data were analyzed using summary statistics.

Results: A total of 41 cases were identified. The median age at time of diagnosis was 34 y. Thirty-three (80%) patients were of Hispanic ethnicity. The most common physical findings were mass (n = 32, 78%), tenderness (n = 17, 41%), and erythema (n = 12, 29%). Three (7%) patients had a previous history of treatment for tuberculosis whereas 12 (29%) patients were human immunodeficiency virus-positive. Mammography and ultrasonography noted mass (n = 14, 34% and n = 15, 37%, respectively) as the most common radiographic finding. Core needle biopsy and incisional biopsy were used with equal frequency (n = 16, 37%) to establish a definitive pathologic diagnosis. The median number of days between onset of symptoms and definitive diagnosis was 73. Thirteen (32%) patients received antibiotics as initial treatment, whereas 23 (56%) underwent surgical procedures and 1 (2%) received steroid therapy. Steroids were used at any point in the clinical course of 7 (17%) patients, and none of these patients required definitive surgical treatment.

Conclusions: GM affects women of childbearing age and typically presents as an inflamed breast mass with or without pain. The clinical features of GM among Hispanic patients are similar to those among other study populations in the reported literature. This disease is a diagnostic and therapeutic challenge and a high degree of clinical suspicion is warranted. Treatment with steroids may obviate the need for surgery in some patients. Reported recurrence rates for GM are high, and long-term follow-up is essential.