929 – Combined intralesional and topical corticosteroids for idiopathic granulomatous mastitis: a prospective pilot case series

Abstract

Introduction: Idiopathic granulomatous mastitis (IGM) is a challenging benign inflammatory breast disease characterized by a relapsing course and lack of standardized treatment. Although systemic corticosteroids are effective, their
use is limited by significant adverse effects. Local therapeutic strategies have gained interest; however, data on combined
intralesional and topical corticosteroid therapy remain scarce.
Objective: To assess the efficacy, recurrence pattern, and safety of a combined local corticosteroid approach in patients
with IGM.
Methods: A prospective pilot case series was conducted in patients with histologically confirmed IGM. Lesions ≤5 cm on
ultrasound were treated with intralesional methylprednisolone (40 mg) at two-week intervals, combined with continuous topical triamcinolone acetonide 0.1% ointment. The primary endpoint was complete clinical and ultrasonographic
remission. Secondary outcomes included time to response, recurrence rate, and adverse events. Systemic corticosteroids
were not used.
Results: Three patients were included. All achieved complete remission after three intralesional injections, with a mean
time to remission of four weeks. Early clinical response was observed within 15 days in all cases. Ultrasonography confirmed progressive lesion reduction, with complete resolution achieved after the second application in most cases. No
treatment-related adverse events were reported. During follow-up (4–7 months), recurrence occurred in two patients
(66%), approximately 60 days after remission. Notably, recurrences were mild and effectively controlled with topical therapy alone, without escalation to systemic or further intralesional treatment.
Conclusion: This combined local corticosteroid regimen demonstrated rapid clinical response, favorable safety, and the
potential to control recurrences without systemic therapy. These findings support a steroid-sparing strategy in IGM management and provide preliminary evidence for a minimally invasive, outpatient-based approach. Larger controlled studies are warranted to validate these results.
Ethics: Research Ethics Committee Approval (CAAE 84914324.4.0000.0253).