Radiologic findings of idiopathic granulomatous mastitis

Abstract

Aim: To describe the radiological findings of idiopathic granulomatous mastitis (IGM). Material and methods: Radiologic findings of 30 women with histopathological diagnosis of IGM were retrospectively evaluated. All had breast feeding history. All the patients had ultrasonography (US), with 12 of them having additional Doppler US. Of 30 patients, 11 had mammography (MG) and 5 MRI. Results: US showed multiple irregular hypoechoic masses and collection areas with tubular connections in 25 of 30. The collection area with low-level internal echoes but without tubular connections, suggesting an abscess were seen in 2 of 30 (6.6%); a hypoechoic mass with an indistinct border in 2 of 30 (6.6%); multiple milimetric hypoechoic nodular masses in 1 of 30 (3.3%). On MG, normal findings were noted in 5 (45.4%); focal asymmetric density in 4 (36.4%), parenchymal distortion in 1 (9%) and diffuse asymmetric opacity with trabecular thickening in 1 (9%) of 30 patients. On MRI, segmental T2 hyperintensity with contrast-enhancement on T1 were seen in 4 of 5 (80%). An enhancing T2 hypointense mass with irregular margin was present in 1 of 5 (20%). Time-signal intensity curve of lesions showed slow enhancement in 1 and moderate in 4 of 5 patients. Conclusions: In IGM, MG findings were nonspecific. In US, multiple irregular hypoechoic masses and collections with tubular connections with fingerlike aspects, and fistulae formation to the skin in patients with breastfeeding history suggested IGM rather than carcinoma. Due to the limited number of patients, no conclusion was reached regarding MRI of IGM.

Imaging Findings in Patients with Granulomatous Mastitis

“…GM is an uncommon inflammatory condition of the breast characterized by granuloma and abscess formation (2), generally affecting young women of reproductive age, mostly during the five years following childbirth (2-8). Until now, the largest patient series reported in the literature was that of Yildiz et al (8), which involved 30 patients with a diagnosis of idiopathic GM.…”

“…Until now, the largest patient series reported in the literature was that of Yildiz et al (8), which involved 30 patients with a diagnosis of idiopathic GM. Thus, to our knowledge, our study represents the second-largest patient series in the literature with an evaluation of radiologic findings of GM.…”

“…MG generally shows non-specific signs, the most common of which is focal asymmetric increased density, ill-defined borders, and mass effect, or irregular masses with ill-demarcated borders (3, 8, 9, 11-15). MG has low sensitivity for this condition, particularly when considering the younger population that is affected, as the abovementioned findings may not be detected in women with dense breast tissue (3, 6, 13, 16).…”

“…The MRI characteristics of GM have been reported in only a few cases in the literature, and data on the use of MRI in GM are scarce, with a variety of definitions used for the description of MRI findings (2, 3, 5, 7, 8, 14, 16). In suspected cases of GM, MRI should not lead to delayed biopsy and may be used as a complementary diagnostic method in addition to US and MG in order to exclude a diagnosis of inflammatory breast cancer in cases with symptoms of treatment-resistant mastitis (17).…”

Idiopathic granulomatous mastitis: a diagnostic challenge

“…Surgical intervention in the form of wide surgical excision was the mainstay of treatment before 1980 and is still performed depending on local expertise and preference. In some rare cases, mastectomy is performed with breast reconstruction [3,4].…”