Abstract
In Japan, the number of breast cancer patients is increasing, with the highest number of cancer-related deaths among women aged 30-69 years. Although early detection and diagnostic screening are emphasized, mammography, a breast cancer screening method, is difficult in patients with implanted devices. We encountered a case of breast cancer detected incidentally during an implantable pulse generator (IPG) replacement. A 60-year-old woman had undegone bilateral subthalamic nucleus deep brain stimulation (DBS) for advanced Parkinson's disease 3.5 years prior. Intraoperatively, an induration measuring approximately 1cm was felt at the IPG implantation site (pocket) in the right thoracic region. A biopsy was performed, submitted for pathological examination, and a new IPG was placed. Pathological examination revealed an invasive ductal carcinoma. Right mastectomy and sentinel lymph node biopsy were performed, and the IPG was removed and reinserted on the left side during the same surgery. According to breast cancer practice guidelines, the patient received adjuvant therapy, including molecular-targeted therapy and chemotherapy, and is currently undergoing follow-up. Patients with DBS who are predisposed to breast cancer may require individual screening using ultrasonography instead of mammography. In patients with implanted devices, including those with DBS along with a predisposition to breast cancer, appropriate screening methods after implantation should be considered, as well the possibility of breast cancer and the need for breast cancer screening.
