Abstract：
OBJECTIVE: No genomic data have been put forth that prove beyond a shadow of doubt that sporadic medullary thyroid cancer (MTC) occurs in infancy, childhood, and/or adolescence.
METHODS: This was a retrospective comparative study of consecutive patients with MTC who had neck surgery at a tertiary center over a 30-year period.
RESULTS: Included were 1252 patients with MTC (337 hereditary and 915 sporadic), of whom 107 (8.5%) were operated before the age of 18 yrs. Only 4 (3.7%) of the 107 pediatric patients, aged 14, 16, 17 and 17 years, had sporadic MTC. These 4 patients, 3 of whom had been referred for completion surgery, revealed much larger thyroid tumors (medians of 20 mm vs. 1.5-5 mm) than the 103 pediatric patients with hereditary MTC. As for extrathyroid extension and nodal metastases, the 4 patients with sporadic MTC were more comparable to the 37 carriers of highest-risk mutations, 31 (84%) of whom were index patients with de novo disease, than to the 66 carriers of high-risk, intermediate-risk, or low-risk RET mutations (25-38% vs. 0-8%, and medians of 9-9.5 vs. 0 node metastases after dissection of more (medians of 72-91.5 vs. 4.5-9) nodes).
CONCLUSIONS: Sporadic MTC, arising rarely, if ever, below the age of 14 years, is exceptional in infancy and childhood, and infrequent in adolescence. At diagnosis, it is almost as widely metastatic as hereditary MTC of the highest-risk category which almost always, like sporadic MTC, presents as de novo disease.
METHODS: This was a retrospective comparative study of consecutive patients with MTC who had neck surgery at a tertiary center over a 30-year period.
RESULTS: Included were 1252 patients with MTC (337 hereditary and 915 sporadic), of whom 107 (8.5%) were operated before the age of 18 yrs. Only 4 (3.7%) of the 107 pediatric patients, aged 14, 16, 17 and 17 years, had sporadic MTC. These 4 patients, 3 of whom had been referred for completion surgery, revealed much larger thyroid tumors (medians of 20 mm vs. 1.5-5 mm) than the 103 pediatric patients with hereditary MTC. As for extrathyroid extension and nodal metastases, the 4 patients with sporadic MTC were more comparable to the 37 carriers of highest-risk mutations, 31 (84%) of whom were index patients with de novo disease, than to the 66 carriers of high-risk, intermediate-risk, or low-risk RET mutations (25-38% vs. 0-8%, and medians of 9-9.5 vs. 0 node metastases after dissection of more (medians of 72-91.5 vs. 4.5-9) nodes).
CONCLUSIONS: Sporadic MTC, arising rarely, if ever, below the age of 14 years, is exceptional in infancy and childhood, and infrequent in adolescence. At diagnosis, it is almost as widely metastatic as hereditary MTC of the highest-risk category which almost always, like sporadic MTC, presents as de novo disease.
摘要：
目的：没有基因组数据可以毫无疑问地证明偶发性甲状腺髓样癌（MTC）发生在婴儿期，童年,和/或青春期。
方法：这是一项回顾性比较研究，研究对象是连续30年在三级中心接受颈部手术的MTC患者。
结果：包括1252例MTC患者（337例遗传性和915例散发性），其中107人(8.5%)在18岁之前手术。107名儿科患者中只有4名（3.7%），14、16、17和17岁，有零星的MTC。这四个病人,其中3人已被转诊为完成手术，显示更大的甲状腺肿瘤(中位数为20毫米vs.1.5-5毫米）比103例遗传性MTC儿科患者高。至于甲状腺外延伸和淋巴结转移，4例散发性MTC患者与37例具有最高风险突变的携带者更具可比性，其中31人（84%）是新发疾病的索引患者，而不是66名高风险携带者，中等风险，或低风险RET突变(25-38%vs.0-8%,和中位数9-9.5vs.0淋巴结转移后更多（中位数为72-91.5vs.4.5-9)节点)。
结论：零星的MTC，很少出现，如果有的话,14岁以下，在婴儿期和童年时期是特殊的，在青春期很少见。诊断时,它几乎与最高风险类别的遗传性MTC一样广泛的转移性，像零星的MTC，表现为新生疾病。
方法：这是一项回顾性比较研究，研究对象是连续30年在三级中心接受颈部手术的MTC患者。
结果：包括1252例MTC患者（337例遗传性和915例散发性），其中107人(8.5%)在18岁之前手术。107名儿科患者中只有4名（3.7%），14、16、17和17岁，有零星的MTC。这四个病人,其中3人已被转诊为完成手术，显示更大的甲状腺肿瘤(中位数为20毫米vs.1.5-5毫米）比103例遗传性MTC儿科患者高。至于甲状腺外延伸和淋巴结转移，4例散发性MTC患者与37例具有最高风险突变的携带者更具可比性，其中31人（84%）是新发疾病的索引患者，而不是66名高风险携带者，中等风险，或低风险RET突变(25-38%vs.0-8%,和中位数9-9.5vs.0淋巴结转移后更多（中位数为72-91.5vs.4.5-9)节点)。
结论：零星的MTC，很少出现，如果有的话,14岁以下，在婴儿期和童年时期是特殊的，在青春期很少见。诊断时,它几乎与最高风险类别的遗传性MTC一样广泛的转移性，像零星的MTC，表现为新生疾病。
