Multiple endocrine neoplasia are syndromes involving two or more endocrine tissues, often correlated to RET
proto-oncogene mutations. We herein present the first reported case of a 57-years-old woman with three synchronous
primary cancers of breast (papillary), thyroid (medullary) and pancreas (neuroendocrine), the latter with liver
metastasis. The patient first underwent surgery for papillary breast cancer with axillary lymph nodes metastases. A
staging whole body computerized tomography (CT) showed a right lateral cervical lymph node, pancreatic
inhomogeneity, peri-pancreatic nodes and a single liver metastasis. The poor response to an antracycline and
taxane-based chemotherapy, the good performance status of patient, and associated symptoms, suggested a different
origin for pancreatic and hepatic lesions. A careful re-evaluation of clinical history, an octreotide-labeled scan and an
immunohistochemical analysis, on both hepatic and pancreatic tissues and on laterocervical lymph node, determined
the diagnosis of synchronous papillary breast cancer, pancreatic neuroendocrine tumor (pNET) with liver metastasis
and an occult medullary thyroid carcinoma in a patient who had proto-oncogene RET wild type
