Idiopathic granulomatous mastitis lesion mimicking inflammatory breast cancer
=============================================================================

* Martin A. Nzegwu
* Kenneth A. Agu
* Peace I. Amaraegbulam

*   © 2007 Canadian Medical Association

A 30-year-old schoolteacher, primiparous, came to our clinic at 4 months postpartum with a 3-month history of a painful swelling in her left breast. It had already been drained on several occasions. She had no history of fever, trauma or use of oral contraceptives; her family history was positive for breast cancer.

A physical examination revealed ulcerated peau d'orange skin (Fig. 1) above a firm, tender, 8–10 cm mass with an ill-defined border and multiple sinuses, in her left breast. Ipsilateral axillary nodes were palpable. Her hemoglobin level was 110 g/L; leukocytes, 5400/mL. Her erythrocyte sedimentation rate was in the normal range, and a radiograph of her chest appeared normal. Results of a Mantoux test were negative. Ultrasound showed a lobulated, homogeneously hypoechoic 4-cm mass in her left breast. Results of an incisional biopsy reported numerous confluent nonnecrotizing granulomas composed predominantly of Langhans-type giant cells with some lymphocytes (Fig. 2).

![Figure1](http://www.cmaj.ca/https://www.cmaj.ca/content/cmaj/176/13/1822/F1.medium.gif)

[Figure1](http://www.cmaj.ca/content/176/13/1822/F1)

**Fig. 1:** Patient with a firm mass having multiple sinuses, in her left breast, before treatment. Note the breast asymmetry.


![Figure2](http://www.cmaj.ca/https://www.cmaj.ca/content/cmaj/176/13/1822/F2.medium.gif)

[Figure2](http://www.cmaj.ca/content/176/13/1822/F2)

**Fig. 2:** Confluent nonnecrotizing granulomas with giant cells.

In our differential diagnosis, we considered tuberculosis, sarcoidosis and fungal granuloma in addition to granulomatous mastitis. In light of the normal Mantoux results, chest radiograph and erythrocyte sedimentation rate, we proceeded with a working diagnosis of idiopathic granulomatous mastitis. We prescribed prednisolone, 20 mg/d; the sinuses and ulcers resolved within 3 weeks (Fig. 3).

![Figure3](http://www.cmaj.ca/https://www.cmaj.ca/content/cmaj/176/13/1822/F3.medium.gif)

[Figure3](http://www.cmaj.ca/content/176/13/1822/F3)

**Fig. 3:** Breast after treatment, with disappearance of the mass and peau d'orange skin.

Idiopathic granulomatous mastitis, sometimes referred to as postlactational tumoral granulomatous mastitis,1 is a rare, benign breast disorder that mimics inflammatory breast cancer. It usually appears during lactation, as a firm, discrete, unilateral mass, and accounts for 0.44%–1.6% of all breast biopsy specimens.2,3 Fine-needle aspiration biopsy does not provide a reliable diagnosis. Over 30 case reports and case series describe it, the largest involving 26 patients.4 Management ranges from conservative measures to the use of corticosteroids and, rarely, excision.

## Footnotes

*   This article has been peer reviewed.
    
    **Competing interests:** None declared.

## REFERENCES

1.  1. Brown KL, Tang PHL. Postlactational tumoural granulomatous mastitis: a localized immune phenomenon. Am J Surg 1979;138:326-9.
    
    [CrossRef](http://www.cmaj.ca/lookup/external-ref?access_num=10.1016/0002-9610(79)90397-0&link_type=DOI) 
    
    [PubMed](http://www.cmaj.ca/lookup/external-ref?access_num=464240&link_type=MED&atom=%2Fcmaj%2F176%2F13%2F1822.atom) 
    
    [Web of Science](http://www.cmaj.ca/lookup/external-ref?access_num=A1979HG92800030&link_type=ISI) 

2.  2. Elsiddig KE, Khalil EA, Elhag IA, et al. Granulomatous mammary disease: ten years' experience with fine needle aspiration cytology. Int J Tuberc Lung Dis 2003;7:365-9.
    
    [PubMed](http://www.cmaj.ca/lookup/external-ref?access_num=12729342&link_type=MED&atom=%2Fcmaj%2F176%2F13%2F1822.atom) 
    
    [Web of Science](http://www.cmaj.ca/lookup/external-ref?access_num=000182127700011&link_type=ISI) 

3.  3. Al Nazer MA. Idiopathic granulomatus lobular mastitis: a forgotten clinical diagnosis. Saudi Med J 2003;24:1377-80.
    
    [PubMed](http://www.cmaj.ca/lookup/external-ref?access_num=14710288&link_type=MED&atom=%2Fcmaj%2F176%2F13%2F1822.atom) 
    
    [Web of Science](http://www.cmaj.ca/lookup/external-ref?access_num=000188701300019&link_type=ISI) 

4.  4. Tse GM, Poon CS, Ramachandram K, et al. Granulomatous mastitis: a clinicopathological review of 26 cases. Pathology 2004;36:254-7.
    
    [CrossRef](http://www.cmaj.ca/lookup/external-ref?access_num=10.1080/00313020410001692602&link_type=DOI) 
    
    [PubMed](http://www.cmaj.ca/lookup/external-ref?access_num=15203730&link_type=MED&atom=%2Fcmaj%2F176%2F13%2F1822.atom) 
    
    [Web of Science](http://www.cmaj.ca/lookup/external-ref?access_num=000221583500006&link_type=ISI)