Management of granulomatous lobular mastitis: an international multidisciplinary consensus (2021 edition).

Granulomatous lobular mastitis (GLM) is a rare and chronic benign inflammatory disease of the breast. Difficulties exist in the management of GLM for many front-line surgeons and medical specialists who care for patients with inflammatory disorders of the breast. This consensus is summarized to establish evidence-based recommendations for the management of GLM. Literature was reviewed using PubMed from January 1, 1971 to July 31, 2020. Sixty-six international experienced multidisciplinary experts from 11 countries or regions were invited to review the evidence. Levels of evidence were determined using the American College of Physicians grading system, and recommendations were discussed until consensus. Experts discussed and concluded 30 recommendations on historical definitions, etiology and predisposing factors, diagnosis criteria, treatment, clinical stages, relapse and recurrence of GLM. GLM was recommended as a widely accepted definition. In addition, this consensus introduced a new clinical stages and management algorithm for GLM to provide individual treatment strategies. In conclusion, diagnosis of GLM depends on a combination of history, clinical manifestations, imaging examinations, laboratory examinations and pathology. The approach to treatment of GLM should be applied according to the different clinical stage of GLM. This evidence-based consensus would be valuable to assist front-line surgeons and medical specialists in the optimal management of GLM.

[Granulomatous lobular mastitis associated with mammary duct ectasia: a clinicopathologic study of 32 cases with review of literature].

OBJECTIVE: To study the clinicopathologic features of granulomatous lobular mastitis and mammary duct ectasia. METHODS: The clinicopathologic data from August 2005 to May 2013 of 32 cases of granulomatous lobular mastitis and mammary duct ectasia were retrospectively reviewed. RESULTS: The age of patients ranged from 26 to 45 years. Two patients had no history of delivery. Fourteen patients had no history of lactation or lactational disorder in the lesional side. Most of the remaining patients had history of breast feeding. Gross examination showed that the lesions were poorly circumscribed and varied from 3 to 12 cm in greatest dimension. Tiny abscess cavities, ranging from 0.1 to 0.5 cm in diameter and containing light yellowish to greyish secretion, were demonstrated. Histologic examination showed granuloma formation and ductal dilatation. Eleven patients had received antibiotic treatment. Twelve cases were complicated by sinus formation related to skin incision and drainage. The duration of follow-up ranged from 5 to 90 months. Three cases showed ipsilateral recurrence and 3 cases had similar pathology in the contralateral breast. Four patients defaulted follow-up. CONCLUSIONS: Granulomatous lobular mastitis is associated with mammary duct ectasia. Accurate pathologic diagnosis is prudent for clinical management and control of local recurrence.

[Granulomatous lobular mastitis: a clinicopathologic study of 68 cases].

OBJECTIVE: To study the clinical and pathologic features of granulomatous lobular mastitis (GLM). METHODS: Sixty-eight cases of GLM were retrieved from the archival file. The clinical data and histologic features were retrospectively reviewed. RESULTS: Sixty-eight patients presented with breast mass. Ulceration in overlying breast skin was seen in 9 cases. Most of the patients had history of breast feeding. None of them had evidence of specific infections involving the breast. The clinical and radiologic features mimicked malignancy. Histologically, GLM was characterized by the presence of non-necrotizing granulomas, usually admixed with neutrophils and associated with benign ductolobular units. The ductolobular architecture was still preserved. The duration of follow up ranged from 6 to 36 months. Four patients suffered from disease recurrence. CONCLUSIONS: GLM shows clinical and radiologic features reminiscent of breast cancer. Correct diagnosis requires histologic examination of the biopsy specimens.