Giant cell arteritis presenting as a breast lesion: report of a case and review of the literature.

Giant cell arteritis (GCA) mainly affects arteries arising from the external carotid arteries, although it may also be responsible for extracephalic clinical presentation related to impairment of vessels other than the carotids, such as the aorta as well arteries of the lower and upper limbs (10%-30% of cases). However, breast involvement is considered to be a rare complication of GCA. We recently observed a case of particular interest as the patient developed superficial mammary arteriolitis, bilaterally, revealing GCA with favorable outcome after institution of steroid therapy. Our case report reinforces the possibility of an unusual presentation of GCA. Indeed, we suggest that an evaluation for GCA affecting the breast should be made in elderly women exhibiting breast nodule(s)/mass(es) associated with other features of GCA (that are: headache, jaw claudication, constitutional signs, polymyalgia rheumatica). Furthermore, we also suggest that the prevalence of breast impairment may be underestimated in GCA as the breast is supplied mainly by 2 branches of the subclavian artery (ie, the internal mammary artery [as in the present case report] and the lateral thoracic artery), which is often involved in GCA.