Sakurai Akihiro, Katai Miyuki, Yumita Wataru, Minemura Kesami, Hashizume Kiyoshi
Department of Aging Medicine and Geriatrics, Shinshu University Graduate School of Medicine, Asahi, Matsumoto, Japan.
Endocrine. 2004 Feb;23(1):45-9. doi: 10.1385/ENDO:23:1:45.
Multiple endocrine neoplasia type 1 (MEN1) is an hereditary tumor syndrome that involves specific endocrine organs such as parathyroids, anterior pituitary gland, and endocrine pancreas. The responsible gene for this syndrome, MEN1, has been isolated and that enabled genetic diagnosis for patients with endocrine tumors and early detection of asymptomatic gene carriers in affected families. Nevertheless, there are a considerable number of patients with MEN1 who have neither family history nor germline MEN1 mutations. In this article, clinical features of such patients are described. Among 53 MEN1 patients we have seen during the last 20 yr, five patients who did not have either MEN1 germline mutation or family history were categorized as MEN1 phenocopy. During the same period, we have also experienced three patients who had primary hyperparathyroidism and adrenocortical tumor but had no apparent family history of endocrine tumors. These patients were considered as MEN1 phenocopy variants and included in the study. The mean age of MEN1 phenocopy patients (including variants) at diagnosis was 48 yr, which was not significantly different from that of probands of familial MEN1 (46 yr) who carry heterozygous MEN1 gene mutations. In the majority of MEN1 phenocopy patients, primary hyperparathyroidism was due to a single parathyroid adenoma. In contrast to a previous report, we found that MEN1 phenocopy patients are not necessarily older than probands of familial MEN1. Phenotypic expression of such patients is variable, thus differentiation of familial MEN1 and MEN1 phenocopy cannot be made based on age and clinical phenotype alone.
1型多发性内分泌腺瘤病（MEN1）是一种遗传性肿瘤综合征，累及特定的内分泌器官，如甲状旁腺、垂体前叶和内分泌胰腺。导致该综合征的基因MEN1已被分离出来，这使得能够对内分泌肿瘤患者进行基因诊断，并在受影响的家族中早期检测无症状基因携带者。然而，有相当数量的MEN1患者既没有家族病史，也没有MEN1基因种系突变。本文描述了这类患者的临床特征。在过去20年中我们诊治的53例MEN1患者中，5例既没有MEN1基因种系突变也没有家族病史的患者被归类为MEN1表型模拟。在同一时期，我们还遇到了3例患有原发性甲状旁腺功能亢进和肾上腺皮质肿瘤但没有明显内分泌肿瘤家族史的患者。这些患者被视为MEN1表型模拟变异体并纳入研究。MEN1表型模拟患者（包括变异体）诊断时的平均年龄为48岁，与携带杂合MEN1基因突变的家族性MEN1先证者的平均年龄（46岁）无显著差异。在大多数MEN1表型模拟患者中，原发性甲状旁腺功能亢进是由单个甲状旁腺腺瘤引起的。与之前的报告相反，我们发现MEN1表型模拟患者不一定比家族性MEN1先证者年龄大。这类患者的表型表达是可变的，因此不能仅根据年龄和临床表型来区分家族性MEN1和MEN1表型模拟。
