Patients with CGM are usually women in their childbearing years and present with a palpable breast lump, indurated plaque, or fluctuant nodule that is typically painful. With progressing disease, fistulas may occur, leading to purulent drainage.
CGM is a diagnosis of exclusion. It is crucial to rule out breast carcinoma with mammography, ultrasound, and core needle biopsy. Core needle biopsy should also be sent for culture to rule out infectious etiologies. In addition, other causes of granulomatous disease, such as sarcoidosis or rheumatologic disease, may be considered.
To date, there is no established treatment algorithm. From case series and case reports, antibiotics, corticosteroids, and/or immunosuppressants may be helpful for some patients. The natural course of the disease is not well-described: some patients spontaneously regress, others improve with therapy, and some relapse or have resistant disease despite treatment.
See also mastitis.
N63.0 – Unspecified lump in unspecified breast
237444008 – Granulomatous mastitis
- Breast carcinoma
- Bacterial infection (eg, Mycobacterium, brucellosis)
- Fungal infection
- Bacterial abscess
- Granulomatosis with polyangiitis
- Foreign body reaction
- Traumatic fat necrosis
- Duct ectasia
- Periductal mastitis
- Lobular panniculitis