Screening for MEN1 mutations in patients with atypical endocrine neoplasia

Background. Most patients from typical multiple endocrine neoplasia type 1 (MEN 1) kindreds harbor mutations in the MEN-I gene, MEN1. We hypothesized that some patients with atypical endocrine neoplasia would also have mutations in MEN1. Methods. DNA sequencing analysis of mutations in the coding region of MEN1 was performed with genomic DIVA obtained from peripheral blood lymphocytes in a total of 21 patients who had: typical MEN 1 (n = 8), clinical features suggestive of MEN 1 but without a family history of endocrinopathy (n = 7), and atypical endocrine neoplasia and a family history of endocrinopathy suggestive of MEN 1 (n = 6). Results, All 8 patients with typical MEN 1 had mutations in MEN1. None of the 7 patients with features of MEN 1, but without a family history of endocrinopathy, had a MEN1 mutation. In contrast, 4 of 6 patients with atypical endocrine neoplasia that included components of MEN 1 and a family history of endocrinopathy had mutations in MEN1, including 2 patients with pheochromocytoma. Conclusions. Genomic mutations in MEN1 may frequently be identified in patients with atypical endocrine neoplasia, especially in the setting of a family history of endocrinopathy. Atypical presentations of MEN 1 may include pheochromocytoma.