Simões-Pereira Joana, Vieira Margarida Silva, Pereira Maria Conceição
Endocrinology Department, Instituto Português de Oncologia de Lisboa, Francisco Gentil, Lisbon, Portugal.
Case Rep Oncol. 2014 Dec 4;7(3):810-4. doi: 10.1159/000369923. eCollection 2014 Sep.
Radiotherapy increases the risk of thyroid cancer (TC); patients submitted to this treatment should undergo a long-term follow-up. Our aim is to describe the features and outcomes of young patients who developed TC after radiotherapy.
At our center, patients undergoing radiotherapy directly or indirectly involving the thyroid are regularly followed up in order to detect early dysfunction or nodules. Herein, we report the cases of 10 patients who were submitted to radiotherapy and developed TC.
Seven patients were irradiated in the neck and 3 in nearby regions. The mean age at the last radiotherapy session was 10 ± 5.5 years. The average time until the appearance of the first thyroid nodule was 14 ± 4.7 years. The mean size increment of the nodules was 2.4 ± 1.6 mm/year. On the first cytology, only 2 results were suspicious of papillary thyroid cancer (PTC). All patients presented a histology of PTC. Eight were in stage I and 2 in stage II. The median follow-up from primary diagnosis to TC and beyond was 20 and 3 years, respectively.
In these patients, cytologies may be difficult to interpret due to persistent benign results. The threshold for surgical indication may be anticipated, considering the increased risk of TC. We report the evolution of these nodules over time, from the end of primary oncological treatment.
放射治疗会增加甲状腺癌（TC）的发病风险；接受这种治疗的患者应进行长期随访。我们的目的是描述放疗后发生TC的年轻患者的特征和结局。
在我们中心，对直接或间接涉及甲状腺的放疗患者进行定期随访，以便早期发现功能障碍或结节。在此，我们报告10例接受放疗后发生TC的患者病例。
7例患者接受颈部放疗，3例接受附近区域放疗。最后一次放疗时的平均年龄为10±5.5岁。首次出现甲状腺结节的平均时间为14±4.7年。结节的平均大小每年增加2.4±1.6毫米。在首次细胞学检查中，只有2例结果怀疑为甲状腺乳头状癌（PTC）。所有患者的组织学检查均为PTC。8例为I期，2例为II期。从原发性诊断到TC及以后的中位随访时间分别为20年和3年。
在这些患者中，由于持续出现良性结果，细胞学检查结果可能难以解释。考虑到TC风险增加，手术指征的阈值可能需要提前确定。我们报告了这些结节从原发性肿瘤治疗结束后的随时间演变情况。
