Evaluation of the treatment effectiveness of oral and intralesional steroids in idiopathic granulomatous mastitis using superb microvascular imaging.

Objectives: The objective of this study was to compare the efficacy of oral and intralesional steroid injection in the treatment of idiopathic granulomatous mastitis (IGM) cases with clinical, ultrasonography (US) and Superb microvascular imaging (SMI) findings.

Methods: A total of 53 patients with newly diagnosed IGM who applied to our outpatient clinic between September 2021 and December 2022 were included. Oral steroid therapy was administered to 26 patients, while intralesional steroid therapy was administered to 27 patients. Pretreatment and postreatment difference of the affected area was compared clinically (Unresponsive to treatment: stable or progression; Partial response: <50% reduction; Near complete response: >50% reduction; Complete response: 100% reduction) and radiologically. Grey scale US (size, skin thickness) and SMI vascular index (SMIvi) for vascularization of the pathological area were noted. Recurrence and side-effect rates at the 6 months were compared.

Results: No statistically significant difference was found in the efficacy of oral steroid and intralesional steroid treatment, both radiologically (P = 0.839) and clinically (P = 0.550). There was a considerable difference in size and SMIvi values before and after treatment (P < 0.001) in patients with an adequate response. There was no significant difference between the two treatment methods in terms of recurrence (P = 0.153) or side effects (P = 1).

Conclusion: Intralesional steroid was as effective as oral steroid treatment in IGM patients, and SMI is a reliable sonographic method that can be used to evaluate clinical findings, treatment response, and patient follow-up.