Two cases of breast pseudoaneurysm following core biopsy: A very rare complication with different treatment options.

Introduction: Breast pseudoaneurysm is a rare complication following breast interventional procedures such as core biopsies and vacuum-assisted biopsies. The occurrence of pseudoaneurysm increases with the conditions of increased breast vascularity like cancer, pregnancy and lactation. Case Report: We present two cases of pseudoaneurysm formation secondary to core biopsies of the breasts. The first patient was an 82-year-old female patient who presented with breast swelling and bruising after multiple clinical core biopsies of the left breast. Our second patient was a 47-year-old lady who presented with a palpable lump following ultrasound-guided core biopsies of the left breast. Ultrasound showed hypoechoic pulsating area with evidence of internal colour flow in connection with a vessel in both cases. Imaging appearances were in keeping with a pseudoaneurysm of the breast. Discussion: Most pseudoaneurysms are secondary to interventional procedures in the breast. Common clinical presentation is a pulsatile, palpable mass at the biopsy site soon after the biopsy or later. On B mode imaging, it presents as a well-circumscribed mass of mixed echogenicity. Typical waveform in spectral Doppler and 'yin-yang' sign in colour Doppler is demonstrated with a turbulent internal flow. There are different treatment options to manage pseudoaneurysms of the breast. Conclusion: Pseudoaneurysm of the breast should be considered if a patient presents with a breast mass/lump close to a recent biopsy site. On clinical examination, pulsatility of the mass should raise the suspicion and definite diagnosis can be made with spectral and colour Doppler US scan.