imaging findings in patients with granulomatous mastitis

Background: granulomatous mastitis (gm) is a rare inflammatory breast disease that may mimic the clinical characteristics and radiologic imaging findings of breast carcinoma. considering the importance of making a correct diagnosis, careful radiologic evaluations and recognition of imaging features are necessary. objectives: the aim of this study was to review the radiological findings and diagnostic value of the imaging in gm. patients and methods: this retrospective study involved a total of 29 patients who were diagnosed with gm between 2009 and 2013 and who underwent mammography (mg) and/or ultrasound (us) examination in addition to magnetic resonance imaging (mri) before diagnosis. results: among 14 patients over 35 years of age who underwent mg imaging, focal asymmetric, ill-defined nodular, or diffusely increased densities were detected in nine (64.3%), two (14.3%), and one (7.1%) subjects, respectively, while there were no pathological findings in two (14.3%) patients. in the overall group of 29 patients, us showed heterogeneous hypoechoic lesions with tubular extensions in 16 (55.2%), well-demarcated heterogeneous hypoechoic lesions in eight (27.6%), parenchymal heterogeneous appearance in three (10.3%), and a heterogeneous hypoechoic lesion with irregular margins in one (3.4%), with another (3.4%) patient having normal us findings. mri findings included lesions consistent with solitary or multiple separate or confluent abscesses with marked peripheral ring enhancement in 25 (86.2%) patients, accompanied by intensity changes suggesting edematous inflammation in the peripheral parenchyma, as well as non-mass-like heterogeneous segmental and regional contrast enhancement. four (13.8%) patients had non-mass-like segmental and regional contrast enhancement only. a histopathological diagnosis of gm was established in all patients with biopsy. conclusion: gm presents with a wide range of conventional radiological findings, hampering the diagnosis. in patients with inconclusive conventional findings, mri may assist in the differential diagnosis and assessment of the extent of disease. however, a definitive diagnosis and relevant treatment require histopathological confirmation.