Idiopathic Granulomatous Lobular Mastitis: An Imitation of Breast Carcinoma

Abstract

Since idiopathic granulomatous lobular mastitis, also known as idiopathic granulomatous mastitis or granulomatous lobulitis, was first described by Kessler and Wolloch in 1972, no consensus on the ideal and definitive treatment for this phenomenon has been reached thus far. Idiopathic granulomatous lobular mastitis mostly frequently observed in women of childbearing age within a few years of pregnancy with a higher incidence in patients of Hispanic, Native American, Middle Eastern, and African descent. This entity, per se, is a rare, benign, chronic inflammatory breast condition of unknown aetiology mimicking two common breast disorders. The first is breast inflammations or infection, such as cystic neutrophilic granulomatous mastitis; granulomatous mastitis due to Corynebacterium; other infections with granulomas, mycobacteria, fungi, cat scratch disease, and Brucella; granulomatosis with polyangiitis (Wegener's granulomatosis); sarcoidosis; and squamous metaplasia of lactiferous ducts. The second is breast carcinoma in some challenging cases. Of note, no consensus, per se, has been declared on its therapeutic management. The following vignette case described in this report involves idiopathic granulomatous lobular mastitis imitating breast carcinoma. It is important to note that, the aetiology of idiopathic granulomatous lobular mastitis is unknown, its diagnosis is difficult, and physicians should be vigilant and aware of this condition in order of abstaining from an overtreatment for malignancy or overlooking a true malignancy.

Clinical features and risk factors of bilateral granulomatous lobular mastitis

“…Distinguishing GLM from breast cancer is particularly difficult, as both conditions exhibit similar clinical symptoms and radiographic features. [12] Symptoms of GLM primarily manifest as irregular, firm breast masses with poor mobility and may also be accompanied by enlargement of the axillary lymph nodes, often leading to misdiagnosis as malignant breast tumors. On mammography, GLM appears as irregular masses and is frequently classified as BI-RADS 4a to 4c, [13] indicating suspicion of malignancy that necessitates further investigation.…”

Granulomatous mastitis secondary to Corynebacterium requiring surgical intervention: a complicated diagnosis

“…Idiopathic granulomatous mastitis (IGM) was first described in 1972, and since then, there has yet been a definitive approach to identify and treat the disease. Although rare, this condition is typically observed more frequently in women of childbearing age and with a higher incidence in Hispanic, Native American, Middle East and African descent [ 1 ]. GM frequently mimics malignancy of the breast and thus, invariably places patients at the center of diagnostic uncertainty [ 2 , 3 ].…”

Clinicopathologic Features and Pathogens of Granulomatous Lobular Mastitis

“…Because of the absence of specific clinical and radiological findings, confusing GLM with breast cancer is common [30,31]. Furthermore, differential diagnoses of GLM include plasma cell mastitis, duct ectasia, sclerosing lymphocytic lobular mastitis, IgG4-related sclerosing mastitis, and other known causes of granulomatous diseases such as tuberculosis, sarcoidosis, fat necrosis, foreign body granuloma, etc.…”