Lupus mastitis in male mimicking a breast lump

Imaging Findings of Lupus Mastitis: A Systematic Review of Case Studies

Lupus mastitis (LM) is a rare manifestation of systemic lupus erythematosus, resulting in an inflammatory process within the breast tissue. This condition presents diagnostic challenges due to its similarity to other breast pathologies, including infections and malignancies. Clinically, patients may exhibit symptoms such as breast pain, swelling, and erythema, often leading to further investigation through imaging and histopathological analysis. Given the absence of established clinical guidelines for LM, identifying the most effective imaging and laboratory techniques is essential for accurate diagnosis and treatment. In this paper, 32 patient case reports were analyzed, with 20 patients having previous diagnoses of lupus and 12 not previously diagnosed. The study population comprised 90.6% (n=29) women, with a mean age of 44 years and an average disease duration of 10 years. The majority of LM was unilateral, with 50% (n=16) of patients experiencing LM in the right breast, 31.2% (n=10) in the left breast, and 18.8% (n=6) bilaterally. The location varied to almost all quadrants of the breast. The rarity of LM contributes to clinician unawareness, often resulting in misdiagnosis and confusion. As there are currently no guidelines, in this study we examined the imaging findings of LM through a variety of modalities and reported a suggested clinical guideline to follow for the diagnoses of LM.

Lupus mastitis with predominant kappa-restricted plasma cell infiltration: report of a rare case

Lupus mastitis (LM) is a rare complication of systemic lupus erythematosus (SLE) or discoid lupus erythematosus (DLE). The clinical presentations of LM may mimic breast malignancy, and biopsy or excision is usually performed. Histologically, LM is featured by lymphoplasmacytic inflammation involving breast ducts, lobules, blood vessels and adipose tissue. Characteristic hyaline fat necrosis can be noted in most cases. Here, we reported a case of LM in an elderly female patient who presented with bilateral breast lesions. Histologically, the breast lesions showed prominent hyaline fat necrosis and predominantly plasmacytic inflammation involving breast ducts, vessels and fat lobules. Fibrinoid necrosis of vessels was also noted. The infiltrated plasma cells were Kappa light chain-restricted, but did not show the immunophenotypes for a plasma cell neoplasm. In addition, the patient developed Kappa-restricted plasma cell myeloma 2 years later. The patient was followed up for 8 years, and her breast lesion did not show recurrence. The patient’s unique clinicopathological presentations indicated a potential correlation between her LM and subsequently developed myeloma. It also indicated that the immunophenotypical characterization of infiltrated plasma cells in LM patients with predominant plasma cell infiltration may be important to rule out potential plasma cell neoplasms.

Lupus mastitis of the male breast

A 39-year-old male with no known co-morbid conditions presented with gradually increasing bilateral breast lumps for 1.5 years. Clinically, tender subcutaneous masses were detected. Mammograms revealed masses on both sides that on ultrasound were hyperechoic and showed internal vascularity. An MRI was suggested to assess the extent of the disease that confirmed bilateral masses but was otherwise inconclusive. Core biopsy revealed evidence of panniculitis with likely autoimmune aetiology. Evaluation of autoimmune markers was carried out that was positive and multidisciplinary team discussion concluded the diagnosis as lupus mastitis. Male breast pathology and lupus mastitis are both uncommon conditions, making lupus mastitis of male breast an extremely unusual presentation. However, its close clinical and radiological similarity with malignancy makes it important in spite of its rarity. Here we report a case of bilateral lupus mastitis in male breast with its radiological features.

Lupus mastitis: an uncommon complication of systemic or discoid lupus

Lupus mastitis is an uncommon presentation of lupus erythematosus profundus or lupus panniculitis, a rare variant of lupus erythematosus characterized by inflammation of the subcutaneous fat. Lupus mastitis can present as single or multiple subcutaneous or deep breast masses, often clinically mimicking malignancy. Although lupus mastitis is rare, with less than 25 cases reported, the histologic features are distinct. Awareness of the entity and familiarity with the histologic features allow for accurate diagnosis and appropriate patient management. It most commonly affects women with a mean age at diagnosis of 40 years and an age range of 18 to 70 years. Typical histologic findings in lupus mastitis include a lymphocytic lobular panniculitis with plasma cells and hyaline fat necrosis. The lymphocytic infiltrate can be nodular, diffuse, periductal, and/or perilobular and germinal centers can frequently be identified. Lymphocytic vasculitis is also common. Immunohistochemistry shows a mixed T and B-cell population, with predominantly CD3+ CD4+ T cells intermixed with CD20-positive B cells and polyclonal plasma cells. Most commonly, lupus mastitis is seen in patients with a previous diagnosis of systemic or discoid lupus; however, it can also be the initial presentation of lupus in some patients. We report on 2 cases of lupus mastitis where the clinical impression was to rule out malignancy and review the literature to highlight the key clinicopathologic features.