Axillary pseudoaneurysm post core needle biopsy

Pseudoaneurysm of the breast following a core needle biopsy: report of two cases

Introduction: Core needle biopsy (CNB) is the gold standard for histopathological diagnosis of breast masses. However, rare complications may occur after undergoing CNB, including hematoma and pseudoaneurysm (PA) of the breast. Cases presentation: Case 1: 66-year-old woman with a left breast mass who underwent a CNB without complications. Around eleven months later, she noticed a palpable and pulsatile mass in her left breast. She was diagnosed with a PA (1.6x1.3 cm) by means of a Doppler ultrasound (US) and a breast magnetic resonance imaging, which was surgically resected without any complication using local anesthesia. Case 2: 44-year-old woman with a left breast mass. After undergoing CNB, she developed ecchymosis and a palpable and pulsatile mass in her left breast. A Doppler US showed a 1.4x0.7 cm cystic lesion suggestive of a breast PA. The mass was surgically resected without complications using local anesthesia and sedation. Conclusion: Breast PA is an extremely rare complication of CNB, with only 17 cases reported in PubMed to date. However, breast PA must be highly suspected in the presence of warning signs such as bleeding, hematoma and a palpable and/or pulsatile breast mass after undergoing CNB.