Family screening in multiple endocrine neoplasia type 1 (MEN 1)

Multiple endocrine neoplasia type 1

Multiple endocrine neoplasia type 1 (MEN 1) is an autosomal-dominant inherited tumor syndrome characterized by hyperplasia and/or tumors in the parathyroid glands, the pancreatic islets, the anterior pituitary and adrenal glands, as well as neuroendocrine tumors in the thymus, lungs and stomach, and tumors in nonendocrine tissues. In 1997, the responsible MEN1 gene was identified as a tumor-suppressor gene and its product was named menin. In this review, guidelines for early diagnosis, including MEN1 gene mutation analysis, and treatment, including periodic clinical monitoring, have been formulated, enabling improvement of life expectancy and quality of life. Identification of menin-interacting proteins has provided new insights into the function of menin, notably involving regulation of gene transcription related to proliferation and apoptosis, genome stability and DNA repair, and endocrine/metabolic homeostasis. In the near future, target-directed intervention may prevent or delay the onset of MEN 1-related tumors.

Pancreatic Neuroendocrine Carcinoma Metastatic to the Breast as Part of the Multiple Endocrine Neoplasia Type 1 Syndrome

Breast metastases from nonmammary tumors are rare. We report here the first case of pancreatic neuroendocrine carcinoma metastatic to the breast in a patient with possible multiple endocrine neoplasia type 1. The diagnosis was supported by histological examination, immunohistochemistry, and ultrastructural analysis. This observation emphasizes the importance of clinical data for an accurate diagnosis, especially during intraoperative examination. When pathologists are faced with an unusual breast tumor larger than 2 cm, we would recommend freezing and/or saving pieces of tissue for ultrastructural analysis, which might help in the diagnosis.