Idiopathic granulomatous mastitis: A retrospective cohort study between 44 patients with different treatment modalities

Background: Idiopathic granulomatous mastitis (IGM) is an uncommon benign chronic inflammatory disease which can clinically and radiographically mimic abscess or breast cancer. Definitive diagnosis was made by histopathology and exclusion of an identifying etiology. Optimal treatment has not been yet established. The aim of this study was to report and describe the clinical signs, radiological findings, managements, clinical course, and clinical outcomes after treatment of IGM. Method: We retrospectively studied IGM medical records of 44 patients in our institute collected from March 1990 to October 2016. The patient characteristics, clinical presentations, radiological findings, microbiological workups, tissue pathology, treatment modalities, outcomes, and follow-up data were reviewed and analyzed. The success rate, recurrence rate and time-to-healing were compared focusing on the treatment modalities to find the proper treatments for IGM patient. Results: Forty-four patients were diagnosed as IGM. The median follow-up time was 20.73 months ranging from 1.26 to 118.8 months while the median time of the diagnosis was 21 days ranging from 2 to 246 days. Due to the follow-up period, only thirty-nine patient data were used for the analysis. In the first setting, 30 patients were treated by surgery, 6 patients were treated by using steroid while other 3 patients were treated by other different treatments. Only 25 from 39 patients (64.10%) were cured by the first modality. The overall median time-to-healing was 84 days while the medians of time-to-healing treated by surgery, steroid and the rest were 75, 114.5, and 238 days respectively. The surgical treatment had the shortest time-to-healing but not statistically significant (p = 0.23). Thirteen patients out of twenty-five (52%) had wound complications after performing an excision. Lastly, five patients out of thirty-nine (12.82%) had recurrence. Conclusion: IGM is an uncommon benign disease which is hardly distinguished from malignancy. There is not a significant difference among treatment modalities in term of time-to-healing and recurrence of disease. The result shows that surgery is outperformed by the shortest healing time. However, the surgical treatment must be chosen with careful due to high rate of wound complications. Multimodality treatment is recommended as the proper treatments for IGM patient.