Liu Qiuli, Tong Dali, Yuan Wenqiang, Liu Gaolei, Yuan Gang, Lan Weihua, Zhang Dianzheng, Zhang Jun, Huang Zaoming, Zhang Yao, Jiang Jun
Department of Urology, Institute of Surgery Research, Daping Hospital, Third Military Medical University, Chongqing, PR China Department of Bio-Medical Sciences, Philadelphia College of Osteopathic Medicine, Philadelphia, PA.
Medicine (Baltimore). 2017 Jan;96(3):e5967. doi: 10.1097/MD.0000000000005967.
Multiple endocrine neoplasia type 2A (MEN2A) is a condition with inherited autosomal dominant mutations in RET (rearranged during transfection) gene that predisposes the carrier to extremely high risk of medullary thyroid cancer (MTC) and other MEN2A-associated tumors such as parathyroid cancer and/or pheochromocytoma. Little is reported about MEN2A syndrome in the Chinese population.
All members of the 3 families along with specific probands of MEN2A were analyzed for their clinical, laboratory, and genetic characteristics. Exome sequencing was performed on the 3 probands, and specific mutation in RET was further screened on each of the family members.
Different mutations in the RET gene were identified: C634S in Family 1, C611Y in Family 2, and C634Y in Family 3. Proband 1 mainly showed pheochromocytoma with MTC, both medullary thyroid carcinoma and pheochromocytoma were seen in proband 2, and proband 3 showed medullary thyroid carcinoma.
The genetic evaluation is strongly recommended for patients with a positive family history, early onset of age, or multiple sites of masses. If the results verified the mutations of RET gene, thyroidectomy should be undertaken as the guide for better prognosis.
2A型多发性内分泌腺瘤病（MEN2A）是一种因RET（转染过程中重排）基因发生常染色体显性遗传突变而导致的疾病，该突变使携带者极易患甲状腺髓样癌（MTC）以及其他与MEN2A相关的肿瘤，如甲状旁腺癌和/或嗜铬细胞瘤。关于中国人群中MEN2A综合征的报道较少。
对3个MEN2A家系的所有成员以及特定先证者进行临床、实验室和遗传学特征分析。对3名先证者进行外显子组测序，并对每个家庭成员进一步筛查RET基因的特定突变。
在RET基因中鉴定出不同的突变：家系1为C634S，家系2为C611Y，家系3为C634Y。先证者1主要表现为嗜铬细胞瘤合并MTC，先证者2同时患有甲状腺髓样癌和嗜铬细胞瘤，先证者3表现为甲状腺髓样癌。
对于有家族史阳性、发病年龄早或有多处肿块的患者，强烈建议进行基因评估。如果结果证实RET基因发生突变，应以甲状腺切除术作为指导以获得更好的预后。
