Therapeutic strategy for granulomatous lobular mastitis: a clinicopathological study of 12 patients

Abstract

Granulomatous lobular mastitis (GLM) is a rare inflammatory pseudotumor. No therapeutic modality for this disease has been established because of its rarity. The purpose of this study is to evaluate the treatment strategies of GLM. Twelve women who met the histological criteria for GLM were retrospectively studied. The clinical data and the presentation, histopathology, and management of the disease were analyzed by reviewing the patients' medical records. The diagnosis of GLM was confirmed histologically by core needle biopsy in 9 cases, by vacuum-assisted biopsy in 2 cases, and by excisional biopsy in 1 case. Ten patients received corticosteroid treatment and another two patients were treated with local excision or incision and drainage. The median initial dosage of corticosteroid (Prednisolone) was 30 mg/day (range: 15-60 mg/day), and the dosages were tapered according to improvement. The median duration of corticosteroid treatment was 5 months (range: 1-12 months). The median follow-up period was 22 months (range: 6-104 months), and no patient treated with corticosteroid demonstrated recurrence. However, patients treated with excision or incision and drainage had recurrences. These results suggest that steroid treatment may be the first choice in treatment strategies for GLM.

Fig. 1

Histological findings showing granulomatous inflammation of the lobules without caseation necrosis (1a, Magnification ×40 and the inserted bar 250μm) and the presence of multinucleated giant cells (Langhans’ cells) and plasma cells (1b, Magnification ×400 and the inserted bar 25μm).

Fig. 2

The following images were from a representative patient No. 8. a) Immunohistochemical findings for IgG expression in the plasma cells from patients with GLM (Magnification ×300 and the inserted bar 25μm). b) Immunohistochemical findings for IgG4 expression in the plasma cells from patients with GLM (Magnification ×300 and the inserted bar 25μm).