Giant cell arteritis of the breast

Giant cell arteritis is a vasculitis which can affect small and large arteries, often involving the temporal artery or ophthalmic artery. However giant cell arteritis can be localised to a single organ, most commonly in the breast. Fewer than 30 cases of giant cell arteritis of the breast have been reported in the literature. We report a case of giant cell arteritis of the breast which was diagnosed incidentally in a 79-year-old woman who underwent wide local excision for breast carcinoma. Giant cell arteritis of the breast may present with unilateral or bilateral breast tenderness, often forming a mass which clinically mimics carcinoma, therefore biopsy is required for definitive diagnosis. Rarely, giant cell arteritis may co-exist with breast carcinoma, as in our case. Giant cell arteritis of the breast can also be associated with systemic symptoms which may resolve with corticosteroid treatment.