Endocrinology Service, Memorial Sloan-Kettering Cancer Center, New York, NY 10021, USA.
Clin Oncol (R Coll Radiol). 2011 May;23(4):268-75. doi: 10.1016/j.clon.2011.01.178. Epub 2011 Feb 15.
Over the last 20 years, nearly 5000 cases of differentiated thyroid cancer have been diagnosed and treated in the regions of Russia, Ukraine and Belarus in young people previously exposed to the Chernobyl radioactive fallout during childhood. At diagnosis, 60-70% of the Chernobyl-related paediatric thyroid cancers had clinically evident cervical lymph node metastases (N1) and 10-15% had distant metastases (M1). Despite early reports suggesting that the paediatric thyroid cancer cases that developed after exposure to Chernobyl fallout were particularly aggressive, it now seems that the initial presentation and early clinical course of most of these cases are very similar to both non-radiation-associated paediatric thyroid cancers and thyroid cancers that arise after exposure to external beam irradiation. Over an average clinical follow-up period of about 10 years, the disease-specific mortality rate in these paediatric thyroid cancer cases that developed after the Chernobyl accident is quite low (1% or less). As would be expected in paediatric thyroid cancer, short-term recurrence rates range from 7 to 28% in published reports (mean 17%). However, long-term studies of paediatric thyroid cancer suggest that although the 30 year disease-specific mortality rate should be about 1%, the risk of developing structural disease recurrence is nearly 30% (of which 80% are expected to be locoregional recurrences and 20% are probably new distant metastases). Projected over 30 years of follow-up, a 1% disease-specific mortality in this cohort of 5000 patients would equate to about 50 deaths directly attributable to thyroid cancer. However, a 30% recurrence rate would also mean that about 1500 patients may develop a clinically meaningful recurrence that would need to be diagnosed and treated. It is imperative that we continue to work with our colleagues in Belarus, Ukraine and Russia to ensure that this large volume of patients destined to develop clinically significant recurrences are diagnosed and treated in a timely manner. Ready access to modern disease detection tools (serum thyroglobulin, postoperative neck ultrasonography, cytology/pathology support, and radioactive iodine scanning) and treatments (surgery for recurrent disease, radioactive iodine therapy) in their major academic centres are mandatory if we expect to achieve the excellent clinical outcomes that should be seen when paediatric thyroid cancer recurrence is diagnosed early and treated appropriately.
在过去的 20 年中，在俄罗斯、乌克兰和白俄罗斯地区，有近 5000 例分化型甲状腺癌在儿童时期曾接触过切尔诺贝利放射性沉降物的年轻人中被诊断和治疗。在诊断时，60-70%的与切尔诺贝利相关的儿科甲状腺癌患者有临床明显的颈部淋巴结转移（N1），10-15%有远处转移（M1）。尽管早期有报道称，暴露于切尔诺贝利沉降物后发生的儿科甲状腺癌病例特别具有侵袭性，但现在看来，这些病例的初始表现和早期临床过程与非辐射相关的儿科甲状腺癌以及暴露于外照射后发生的甲状腺癌非常相似。在平均约 10 年的临床随访期间，这些在切尔诺贝利事故后发生的儿科甲状腺癌病例的疾病特异性死亡率相当低（1%或更低）。正如在儿科甲状腺癌中所预期的那样，在已发表的报告中，短期复发率范围为 7%至 28%（平均为 17%）。然而，对儿科甲状腺癌的长期研究表明，尽管 30 年疾病特异性死亡率应为 1%左右，但结构性疾病复发的风险接近 30%（其中 80%预计为局部复发，20%可能为新的远处转移）。在 30 年的随访中预测，在这 5000 例患者中，1%的疾病特异性死亡率相当于约 50 例直接归因于甲状腺癌的死亡。然而，30%的复发率也意味着约 1500 例患者可能会出现需要诊断和治疗的临床意义上的复发。我们必须继续与白俄罗斯、乌克兰和俄罗斯的同事合作，以确保这一大批注定会出现临床显著复发的患者能够及时得到诊断和治疗。如果我们期望在早期诊断和适当治疗时达到应有的出色临床结果，那么在他们的主要学术中心中获得现代疾病检测工具（血清甲状腺球蛋白、术后颈部超声、细胞学/病理学支持以及放射性碘扫描）和治疗（复发性疾病的手术、放射性碘治疗）的便捷途径是必不可少的。
