AB1053 EFFECTIVENESS OF METHOTREXATE IN IDIOPATHIC GRANULOMATOUS MASTITIS TREATMENT
Authors: D. Yalcin Kehribar, T. Izci Duran, A. Kamali Polat, M. Ozgen
Journal: Annals of the Rheumatic Diseases (2020)

Background: Idiopathic granulomatous mastitis (IGM) is a rare inflammatory disease of the breast [1], for which there is a lack of consensus on the treatment protocol [2, 3]; it requires long-term follow-up and is associated with a high rate of relapse after surgical treatment. In this study, we report on the largest single-center cohort of idiopathic granulomatous mastitis treated with steroids + methotrexate. Objectives: We present this study believing that our experience with patients with IGM and use of steroid + methotrexate treatment in them will contribute to the literature. Methods: We retrospectively examined the data of 33 patients histopathologically diagnosed with idiopathic granulomatous mastitis who were evaluated by our Rheumatology or General Surgery Clinics between 2013 and 2016. Results: Of the 33 female patients (age: 38.64 ± 6.9 years), 24 were admitted with an initial diagnosis of Idiopathic granulomatous mastitis, whereas 9 were admitted after surgical treatment. The breast symptoms and laboratory values of the patients before and after the steroid and methotrexate treatment are shown in Table 1. Remission was achieved in 87.9% patients with steroid + methotrexate treatment, and there were no relapses during the 24-month follow-up. Table 2. Pre- and post-treatment laboratuary and clinical findings. Pre-treatment Post-treatment P value ESR (mm/h) 42.45±28.88 17.24±11.31 &lt;0.001* CRP (mg/L) 24.72±35.32 5.37±6.5 0.004* Mass Size (mm) 36.94±16.40 10.79±15.01 &lt;0.001* Fistula (n) 15/33 (45%) 2/33(6%) &lt;0.001** Nipple discharge(n) 17/33(52%) 1/33(3%) &lt;0.001** ESR: Erythrocyte sedimentation rate; CRP: C-reactive protein; *Paired T Test;**Chi-Square test. Conclusion: Methotrexate has so far been added to IGM treatment in order to decrease steroid dosage or to treat relapses, and it has been reported to be effective in case study and a limited number of studies with few patients [2, 4, 5]. Steroid + methotrexate treatment used by us in patients with IGM, which is a rare disease and for which no consensus exists regarding the treatment protocol, is effective and reliable in providing clinical improvement and long-term remission. Therefore, this treatment appears to be successful owing to long-term remission outcomes and very low relapse rates, without the patients having to undergo a surgical procedure and experience the associated anxiety and complications. References: [1]Kessler, E. and Y. Wolloch, Granulomatous mastitis: a lesion clinically simulating carcinoma. Am J Clin Pathol, 1972. 58(6): p. 642-6. [2]Schmajuk, G. and M.C. Genovese, First report of idiopathic granulomatous mastitis treated with methotrexate monotherapy. J Rheumatol, 2009. 36(7): p. 1559-60. [3]Patel, R.A., et al., Idiopathic granulomatous mastitis: case reports and review of literature. J Gen Intern Med, 2010. 25(3): p. 270-3. [4]Sheybani, F., et al., Treatment for and clinical characteristics of granulomatous mastitis. Obstet Gynecol, 2015. 125(4): p. 801-7. [5]Aghajanzadeh, M., et al., Granulomatous mastitis: Presentations, diagnosis, treatment and outcome in 206 patients from the north of Iran. Breast, 2015. 24(4): p. 456-60. Disclosure of Interests: None declared