A Case of Breast Cancer Located Directly Above an Implantable Pacemaker

Abstract

A 79-year-old woman presented with a mass in the two o'clock position of her left breast. She had a history of right mastectomy for right breast cancer 20 years ago and pacemaker (PM) implantation for arrhythmia 16 years ago. Physical examination revealed induration not only in the 2 o'clock direction but also directly above the implanted PM. A needle biopsy of the mass revealed invasive ductal carcinoma of the breast. Fluorodeoxyglucose-positron emission tomography showed a strong accumulation in the mass directly above the PM, as well as in the main mass, suggesting multiple breast cancers on the same side of the PM. After conversion to leadless PM, a left total mastectomy and axillary lymph node dissection were performed, with PM resection. Pathological examination confirmed that the mass just above the PM was also an independent invasive carcinoma. The tumor's resection margins were negative. Herein, we have reported the diagnosis and treatment of PM-associated breast cancer, with a literature review.