Omür Ozgür, Ozcan Zehra, Yazici Bülent, Akgün Ayşegül, Oral Aylin, Ozkiliç Hayal
Ege University, Medical Faculty, Department of Nuclear Medicine, Izmir, Turkey.
Endocr J. 2008 May;55(2):365-72. doi: 10.1507/endocrj.k07e-058. Epub 2008 Feb 15.
Patients with differentiated thyroid carcinoma (DTC) have long-life expectancy and are at risk for developing a second primary cancer. Aim of this study was to assess the occurrence of DTC in conjunction with other primary neoplasms. It was also aimed to explore the possibility of synchronous or metachronous other malignancies having an impact on clinical course of thyroid carcinoma.
MATERIAL & METHODS: Clinical records of 1680 DTC patients treated and followed in our institution over last twenty years were reviewed. Forty-five second primary tumors were found in 42 patients. These patients were classified into 3 groups as antecedent (group I), synchronous (group II) or subsequent (group III) according to the timing of occurrence of non-thyroidal malignancy. The initial characteristics of thyroid neoplasm were compared between patients with DTC plus another tumor and DTC only. Kaplan-Meier Survival Analysis was used to estimate the survival probability for patients with DTC alone and DTC plus another primary tumor.
There were 15 synchronous and 30 metachronous tumors in 42 patients. Three of them had triple tumors. The most common second primary was lympho-haematological and upper aero digestive system tumors in group I and II respectively, whereas a variety of tumors were noted in group III. Despite the more common occurrence of unfavourable prognostic factors in patients with multiple cancers than thyroid cancer alone, complete response to radioiodine therapy and recurrence free survival rate was similar in both groups (p>0.05).
The results of the current series imply that the occurrence of multiple primary tumors is not uncommon in patients with DTC. Close medical surveillance and the use of advanced screening modalities might lead to the detection of second primary tumors in DTC. However, the presence of second primary seems not to affect the clinical course of DTC.
分化型甲状腺癌（DTC）患者预期寿命较长，有发生第二原发性癌症的风险。本研究的目的是评估DTC与其他原发性肿瘤同时发生的情况。同时还旨在探讨同步或异时性其他恶性肿瘤对甲状腺癌临床病程产生影响的可能性。
回顾了过去二十年间在我们机构接受治疗和随访的1680例DTC患者的临床记录。在42例患者中发现了45个第二原发性肿瘤。根据非甲状腺恶性肿瘤发生的时间，将这些患者分为3组：先行组（I组）、同步组（II组）或后续组（III组）。比较了DTC合并另一肿瘤患者与单纯DTC患者甲状腺肿瘤的初始特征。采用Kaplan-Meier生存分析来估计单纯DTC患者和DTC合并另一原发性肿瘤患者的生存概率。
42例患者中有15个同步肿瘤和30个异时性肿瘤。其中3例有三种肿瘤。I组和II组中最常见的第二原发性肿瘤分别是淋巴造血系统肿瘤和上呼吸消化道系统肿瘤，而III组中则发现了多种肿瘤。尽管与单纯甲状腺癌患者相比，多种癌症患者中不良预后因素更常见，但两组对放射性碘治疗的完全缓解率和无复发生存率相似（p>0.05）。
本系列研究结果表明，DTC患者中发生多种原发性肿瘤并不罕见。密切的医学监测和使用先进的筛查方式可能会发现DTC患者的第二原发性肿瘤。然而，第二原发性肿瘤的存在似乎并不影响DTC的临床病程。
