Abstract
A female patient in her thirties who had been followed after operation for a pancreatic neuroendocrine tumor presented to our department because of a left breast tumor. Digital examination and palpation revealed an about 2-cm palpable tumor in the AC area of the left breast. Echography of the breast revealed a 21×18×17mm irregular-shaped, ill-defined and hypoechoic tumor. Fine needle aspiration cytology biopsy from the same site resulted in class V, suggestive of dudtal carcinoma. However, an abdominal CT scan showed multiple swollen lymph nodes in the abdominal cavity. From her clinical course, recurrence of the pancreatic tumor was likely, and the breast tumor was suspected to be the metastatic lesion. Ultrasonography-guided Vacora biopsy was performed. The histopathological diagnosis was neuroendocrine tumor. Breast metastasis was strongly suggested, but a possibility of neuroendocrine tumor of the breast could not be ruled out, and excisional biopsy was performed. No ductal lesions were present in the excised tumor. Breast metastasis of pancreatic neuroendocrine tumor was thus diagnosed.
As we experienced a case of a pancreatic neuroendocrine tumor with breast metastasis which is rare and was difficult to diagnose, we report the case here.
