Corsello S M, Lovicu R M, Migneco M G, Rufini V, Summaria V
Istituto di Endocrinologia, Università Cattolica del S. Cuore, Policlinico A. Gemelli, Roma.
Rays. 2000 Apr-Jun;25(2):257-66.
Medullary thyroid carcinoma is the least frequent thyroid neoplasm; it originates in thyroid parafollicular cells (calcitonin secreting C cells). In 80% of cases it is sporadic, in the remaining 20% it is familial, associated or not to other endocrinopathies as pheochromocytoma and hyperparathyroidism (MEN 2A, MEN 2B, and isolated familial medullary thyroid carcinoma). Preclinical diagnosis in relatives of affected subjects (preferably at pediatric age) is essential for successful therapy and is performed with genetic and biochemical screening tests. The genetic screening is based on DNA analysis (RET proto-oncogene mutations) of the patient, and if positive of all first degree relatives, to separate sporadic (somatic mutations) from familial (germline mutations) forms. The biochemical screening is based on calcitonin determination and its increase after pentagastrin stimulation, (a peculiar characteristic of medullary thyroid carcinoma, the first biochemical disorder in a subject at risk) and is mainly used in genetically silent familial medullary thyroid carcinoma. The principal negative prognostic factors of medullar thyroid carcinoma and the debate concerning the use of calcitonin determination in the diagnosis of the "cold" thyroid nodule have been analyzed.
甲状腺髓样癌是最不常见的甲状腺肿瘤；它起源于甲状腺滤泡旁细胞（分泌降钙素的C细胞）。80%的病例为散发性，其余20%为家族性，与其他内分泌疾病如嗜铬细胞瘤和甲状旁腺功能亢进相关或不相关（MEN 2A、MEN 2B和散发性家族性甲状腺髓样癌）。对受影响患者亲属进行临床前诊断（最好在儿童期）对成功治疗至关重要，可通过基因和生化筛查试验进行。基因筛查基于对患者的DNA分析（RET原癌基因突变），如果所有一级亲属检测结果为阳性，则可区分散发性（体细胞突变）和家族性（种系突变）形式。生化筛查基于降钙素测定及其在五肽胃泌素刺激后的升高（甲状腺髓样癌的一个特殊特征，是高危个体的首个生化紊乱），主要用于基因沉默的家族性甲状腺髓样癌。本文分析了甲状腺髓样癌的主要负性预后因素以及关于降钙素测定在“冷”甲状腺结节诊断中的应用的争论。
