Retrospective Analysis of Idiopathic Granulomatous Mastitis: Its Diagnosis and Treatment

Abstract

Purpose: Idiopathic granulomatous mastitis (IGM) is a rare disease characterized by noncaseating granulomatous inflammation of unknown origin. Because its clinical features are similar to those of other type of mastitis or breast cancer, accurate diagnosis and adequate treatment are essential to ensuring a short symptom duration and improving the quality of life. Methods: The clinical, radiologic, pathophysiologic, and treatment data for 43 patients diagnosed with IGM at the Breast Cancer Center of Gachon University Gil Medical Center between 2005 and 2016 were retrospectively reviewed. Results: Forty-one patients (95.34%) were of childbearing age, seven (16.27%) had a history of lactation, and five (11.62%) had a history of oral contraceptive use. In terms of radiologic findings, 30 patients (69.77%) were diagnosed with Breast Imaging-Reporting and Data System category ≥4A lesions. Corticosteroid therapy was administered to 36 patients (83.72%); overall, 18 patients (41.86%) did not require surgery and 25 patients (58.13%) underwent partial or total mastectomy. Twelve patients (27.90%) developed recurrence. Conclusion: IGM is a benign disease that can be misdiagnosed as breast cancer because of its similar clinical and radiologic findings. Proper diagnosis and treatment can be difficult, but delays may lead to prolonged pain and cosmetic and socioeconomic problems. Efforts should be aimed at establishing the cause of IGM and developing efficient protocols for its diagnosis and treatment.