Thirty-one patients were diagnosed with IGM. All had previously failed oral antibiotic therapies. Seven patients declined initial treatment, subsequent treatment, or did not follow-up. Nineteen experienced symptomatic improvement after 3 months on regimens that commonly included combination prednisone taper (starting at 40-60mg per day) and a disease modifying agent (DMA) such as methotrexate or mycophenolate mofetil (when methotrexate was contraindicated due to abnormal liver tests or alcohol use; Table 1). Notably, 61.5% achieved complete response after 6 months of therapy with a DMA. Methotrexate (oral or subcutaneous) dosing was initiated at 15 mg per week, increasing up to 25 mg weekly and mycophenolate mofetil was initiated at 500 mg once or twice daily with increased titration up to 1.5 g twice daily based on response. Though prednisone monotherapy often prompted partial response, most patients experienced flaring during taper, subsequently requiring a DMA for disease control. Due to significant morbidity, one patient underwent bilateral mastectomy.
In accordance with prior reports,4,5 our patients achieved best outcomes using a combination of corticosteroid taper and DMA. A significant number of our patients had reservations regarding use of methotrexate due to side effect concerns or desire to conceive in the immediate future and some preferred a trial of doxycycline for anti-inflammatory effects. Our study is limited by the small sample size and the lack of validated outcome measures for IGM. Without standard therapeutic protocols for IGM,3-5 additional research is warranted to delineate therapeutic regimens that address the clinical spectrum of disease.
In accordance with prior reports,4,5 our patients achieved best outcomes using a combination of corticosteroid taper and DMA. A significant number of our patients had reservations regarding use of methotrexate due to side effect concerns or desire to conceive in the immediate future and some preferred a trial of doxycycline for anti-inflammatory effects. Our study is limited by the small sample size and the lack of validated outcome measures for IGM. Without standard therapeutic protocols for IGM,3-5 additional research is warranted to delineate therapeutic regimens that address the clinical spectrum of disease.
DISCLOSURES
The authors have no conflicts of interest to declare.
REFERENCES
1. Grover H, Grover SB, Goyal P, et al. Clinical and imaging features of idiopathic granulomatous mastitis - the diagnostic challenges and a brief review. Clin Imaging. 2021;69:126-132.
2. Korkut E, Akcay MN, Karadeniz E, Subasi ID, Gursan N. Granulomatous mastitis: A ten-year experience at a university hospital. Eurasian J Med. 2015;47(3):165-173.
3. Wu JM, Turashvili G. cystic neutrophilic granulomatous mastitis: An update. J Clin Pathol. 2020;73(8):445-453.
4. Kehribar DY, Duran TI, Polat AK, Ozgen M. Effectiveness of methotrexate in idiopathic granulomatous mastitis treatment. Am J Med Sci. 2020;360(5):560-565.
5. Postolova A, Troxell ML, Wapnir IL, Genovese MC. Methotrexate in the treatment of idiopathic granulomatous mastitis. J Rheumatol. 2019;47(6):924-927.
2. Korkut E, Akcay MN, Karadeniz E, Subasi ID, Gursan N. Granulomatous mastitis: A ten-year experience at a university hospital. Eurasian J Med. 2015;47(3):165-173.
3. Wu JM, Turashvili G. cystic neutrophilic granulomatous mastitis: An update. J Clin Pathol. 2020;73(8):445-453.
4. Kehribar DY, Duran TI, Polat AK, Ozgen M. Effectiveness of methotrexate in idiopathic granulomatous mastitis treatment. Am J Med Sci. 2020;360(5):560-565.
5. Postolova A, Troxell ML, Wapnir IL, Genovese MC. Methotrexate in the treatment of idiopathic granulomatous mastitis. J Rheumatol. 2019;47(6):924-927.
AUTHOR CORRESPONDENCE
Flavia Fedeles MD ffedeles@mgh.harvard.edu
