Treatment of Granulomatous Mastitis With Steroids: Should the Decision to End the Treatment be Made Radiologically?

Objective: Idiopathic granulomatous mastitis (IGM) is a benign inflammatory breast disease of unknown etiology that affects women in their reproductive period. The most commonly preferred option as first-line treatment is steroids, but the lack of a standard treatment protocol and high recurrence rate after treatment constitutes a recurring challenge during its management. The aim of this study was to investigate whether the decision to end the treatment should be made radiologically or clinically. Materials and Methods: This retrospective cohort study included IGM patients who had complete clinical recovery with steroids and were followed for a minimum of 30 months. Patient demographics, disease severity and findings, treatment regimens and duration, and magnetic resonance imaging (MRI) findings at clinical recovery were assessed for their relation to recurrence. Results: Eighty-nine patients who were clinically completely healed after steroid treatment for IGM were included in the study. At the time of clinical healing, 51 (57.3%) patients had a complete radiological response and 38 (42.7%) had a partial radiological response (PRR) on MRI. Overall, recurrence developed in 22 (24.7%) patients after a median 38.6-month follow-up. Patients who experienced recurrence were significantly older and had PRR when their treatment was stopped upon clinical healing. Conclusion: During the process of clinical healing, the imaging findings revealed that the remaining disease seems to be a significant predictor for recurrence in IGM patients. In patients with PRR, extending the treatment with either prolonged steroid therapy or by surgical excision of the occult residual disease may prevent recurrences in IGM patients.