Idiopathic Granulomatous Lobular Mastitis - Report of 43 Cases from Iran; Introducing a Preliminary Clinical Practice Guideline

Background: We aimed to report a large series of idiopathic granulomatous lobular mastitis (IGLM) from Iran and sketch preliminary clinical practice guidelines (CPG) for approaching an inflammatory breast mass. Patients and Methods: In a retrospective records review, 43 consecutive IGLM cases were studied. Data on baseline, clinical, imaging, and pathologic characteristics were collected. Results: The mean age of the women was 33.5 years. All but 1 were married and had given birth. 16% had a cancer-like presentation. Inflammatory signs, architectural distortion, and a nodular pattern were the most common findings clinically, mammographically and ultra-sonographically, respectively. 29.5% of the pathological reports indicated necrosis which was more common in younger subjects (p = 0.016); microabscesses were associated with a shorter lactation course (p = 0.006). Corticosteroids had been used as the initial treatment modality in 51%, immunosuppressive agents had not been administered, and a 16% relapse rate was recorded. We recognized the need for a multidisciplinary approach covering radiology, oncology, and surgery to best handle diagnostic and therapeutic issues and manage relevant infections as well as the major differential diagnosis, i.e. malignancy. Conclusion: We hypothesized that a shorter lactation period may cause more milk stasis and extravasation and be contributory to IGLM. CPGs are needed to incorporate the needed multidisciplinary approach and to standardize IGLM care. We present one such guideline.