Epidemiology and Biostatistics Unit, Aviano Cancer Center, IRCCS, Aviano, Italy.
Thyroid. 2012 Jan;22(1):27-34. doi: 10.1089/thy.2011.0038.
The incidence of thyroid cancer (TC) has been increasing over the last 30 years in several countries, with some of the worldwide highest TC incidence rates (IRs) reported in Italy. The objectives of this study were to evaluate by histological subtypes the geographical heterogeneity of the incidence of TC in Italy and to analyze recent time trends for papillary thyroid carcinoma (PTC) in different cancer registries (CRs).
The study included cases of TC (<85 years of age) reported to 25 Italian CRs between 1991 and 2005. Age-standardized IRs were computed for all histological subtypes of TC according to CRs. Estimated annual percent change and joinpoint regression analysis were used for analysis of PTC.
In women, IRs of PTC ranged between 3.5/100,000 in Latina and 8.5/100,000 in Sassari for the period 1991-1995 (a 2.4-fold difference) and between 7.3/100,000 in Alto Adige and 37.5/100,000 in Ferrara for 2001-2005 (a 5.1-fold difference). In men, IRs ranged between 0.7/100,000 in Latina and 3.4/100,000 in Sassari for the period 1991-1995 (a 4.9-fold difference) and between 2.0/100,000 (Alto Adige, Trento) and 10.6/100,000 in Ferrara for 2001-2005 (a 5.3-fold difference). In both sexes, IRs significantly higher than the pooled estimates emerged for the most recent period in the majority of CRs located within the Po River plain and in Latina, but they were lower in the Alpine belt. For women, CRs reported higher IRs than pool estimates showed, between 1991 to 2005, a significantly more marked annual percent change (+12%) than other CRs (+7%). For men the corresponding estimates were +11% and +8%.
The distribution of PTC does not lend support to a role of environmental radiation exposure due to the Chernobyl fallout, iodine deficiency, or (volcanic) soils. Between 1991 and 2005, wide geographic variations in the incidence of PTC and heterogeneous upward trends emerged, suggesting that the heterogeneity was a relatively recent phenomenon; this appeared to be mainly explained by variations, at a local level, in medical surveillance.
在过去的 30 年中，几个国家的甲状腺癌（TC）发病率一直在上升，意大利报告的 TC 发病率（IR）是世界上最高的。本研究的目的是通过组织学亚型评估意大利 TC 发病率的地域差异，并分析不同癌症登记处（CR）中乳头状甲状腺癌（PTC）的近期时间趋势。
本研究纳入了 1991 年至 2005 年间 25 个意大利 CR 报告的 TC（<85 岁）病例。根据 CR 计算了所有 TC 组织学亚型的年龄标准化发病率。采用估计年度百分比变化和连接点回归分析方法分析 PTC。
在女性中，1991-1995 年期间，皮拉提诺（Latina）的 PTCIR 为 3.5/100,000，萨萨里（Sassari）为 8.5/100,000（相差 2.4 倍），2001-2005 年期间，上阿迪杰（Alto Adige）为 7.3/100,000，费拉拉（Ferrara）为 37.5/100,000（相差 5.1 倍）。在男性中，1991-1995 年期间，皮拉提诺（Latina）的 PTCIR 为 0.7/100,000，萨萨里（Sassari）为 3.4/100,000（相差 4.9 倍），2001-2005 年期间，上阿迪杰（Alto Adige）和特伦托（Trento）为 2.0/100,000，费拉拉（Ferrara）为 10.6/100,000（相差 5.3 倍）。在两性中，在波河平原和拉提纳（Latina）的大多数 CR 中，最近时期的发病率均明显高于汇总估计值，但在阿尔卑斯带则较低。对于女性，与 pooled 估计相比，CR 报告的发病率更高，1991 年至 2005 年间，与其他 CR 相比（+7%），明显呈更显著的年度百分比变化（+12%）。对于男性，相应的估计值分别为+11%和+8%。
PTC 的分布不支持切尔诺贝利核事故、碘缺乏或（火山）土壤引起的环境辐射暴露的作用。1991 年至 2005 年间，PTC 的发病率出现了广泛的地域差异和不均匀的上升趋势，表明这种差异是一个相对较新的现象；这似乎主要是由于当地医疗监测的差异造成的。
