Tattoo Pigment in an Intramammary Lymph Node Mimicking Breast Malignancy

There are many patterns of microcalcification in mammography. Distinguishing between these patterns can be challenging. A malignant cause needs to be assessed through further diagnostic workup. We present a case of a 36-year-old BRCA1 mutation carrier, presenting with a small mass containing calcification on her screening mammogram. A vacuum-assisted biopsy under tomosynthesis guidance was performed and demonstrated an intramammary lymph node showing prominent extracellular black pigment. To our knowledge, this is the first case report of tattoo pigment mimicking breast malignancy on mammography.