Granulomatous mastitis: etiology, imaging, pathology, treatment, and clinical findings

Breast Cancer Res Treat. 2018 Oct;171(3):527-534. doi: 10.1007/s10549-018-4870-3. Epub 2018 Jul 3.


Purpose: To outline the demographics, clinical presentation, imaging features, and treatment modalities observed among a series of patients diagnosed with biopsy-proven granulomatous mastitis (GM).

Method: Following approval by institutional review board, retrospective chart review was performed on patients with biopsy-proven granulomatous mastitis at our institution in the period from January 2013 until October 2017.

Results: A total of 90 patients were identified: 87 women and 3 men. The mean age was 35 years, mostly women in their reproductive age. In our study, patients with GM were more likely to be Hispanic compared to the general population. Sixty-three percent of patients were within 5 years of previous pregnancy. Painful palpable mass-like lesion was the most common physical finding. Breast ultrasound (US) was performed in all patients, and most commonly showed a hypoechoic irregular-shaped mass. Mammography (MG) showed asymmetry or irregular mass as the main finding. Definitive diagnosis was obtained by imaging-guided core needle biopsies in 94.4%. Conservative management was preferred, and only one patient underwent surgery.

Conclusion: Although clinical and radiological findings of patients with GM may mimic those of breast carcinoma, our study showed that women of childbearing age, especially among Hispanic ethnicity with a recent history of pregnancy or high prolactin level and newly tender mass-like lesion, in addition to new focal asymmetry on mammogram and heterogeneous hypoechoic irregular-shaped mass on ultrasound exam, should raise concern for GM. Non-invasive approach and clinical follow-up were the preferred treatment method.

Keywords: Breast cancer; Breast imaging; Breast mass; Granulomatous mastitis.

Publication types

  • Review

MeSH terms

  • Adult
  • Biopsy
  • Breast Neoplasms / diagnosis*
  • Breast Neoplasms / diagnostic imaging
  • Breast Neoplasms / epidemiology
  • Breast Neoplasms / pathology
  • Diagnosis, Differential*
  • Female
  • Granulomatous Mastitis / diagnosis*
  • Granulomatous Mastitis / diagnostic imaging
  • Granulomatous Mastitis / epidemiology
  • Granulomatous Mastitis / pathology
  • Hispanic or Latino
  • Humans
  • Male
  • Mammography
  • Ultrasonography, Mammary