Type:
Educational Exhibit
Keywords:
Abscess, Biopsy, Ultrasound, MR, Mammography, Breast
Authors:
N. Alberdi, P. Lopez Sala, G. Unzue, T. Lage Vidal, L. A. De Llano Ibisate, C. Saavedra Gutierrez, N. Baraibar Argota, I. San Martin San martin, C. Alfaro; Pamplona/ES
DOI:
10.26044/ecr2019/C-1358
Background
Idiopathic granulomatous mastitis,
also known as nonpuerperal mastitis or granulomatous lobular mastitis,
is a benign,
rare and chronic inflammatory disease of the breast of unknown etiology.
It usually has a recurrent or prolonged natural disease course.
Although it is a benign condition,
it is important because it clinically and radiographically mimics breast cancer,
especially inflammatory type (1).
The etiology of IGM is unknown but some factors have been stated,
including reaction to chemical materials,
infectious disease,
autoimmune diseases and immunologic response for milk leakage from breast lobule.
Thus,
some conditions such as pregnancy,
lactation or hyperprolactinemia have been associated such as risk factors (1,
2).
IGM can have a wide range of clinical and imaging manifestations that can difficult the final diagnosis.
The most frequent clinical signs are unilateral breast mass,
pain,
skin erythema,
edema and warmth in a woman,
usually within 6 years of pregnancy (3,
4,
5).
Ultrasonography,
mammography,
and MRI are useful for imaging evaluation.
Nevertheless,
idiopathic granulomatous mastitis mimics a breast carcinoma clinically very often,
so core-needle biopsy,
with or without fine-needle aspiration for cytopathologic examination is usually required (3,
4,
6).
Patients with IGM have an excellent prognosis when they are appropriately treated with oral steroids or second-line immunosuppressive and prolactin-lowering medications,
even with imaging surveillance alone.
However,
surgical excision may be an option for patients in whom medication therapy is unsuccessful (2).