RESUMO
BACKGROUND: Amyloidosis is an uncommon disorder characterized by the extracellular deposition of amorphous and insoluble proteins in an abnormal fibrillary configuration. Mammary amyloidosis is an unusual and easily overlooked diagnosis with an ambivalent presentation that could mimic breast cancer. CASE REPORT: We here report the case of 60-year-old Caucasian woman who presented to our surgical oncology department for clinically and radiologically suspicious breast mass. A fine needle biopsy was irrelevant, so we performed a lumpectomy. Final histology revealed an amyloid deposit and further workup was consistent with nodular cutaneous and breast AL amyloidosis associated with Sjögren's syndrome. CONCLUSION: Although rare, an awareness of the clinicopathologic characteristics of this easily overlooked entity is of great importance for breast surgeons.