de Jong Pim A, Mayo John R, Golmohammadi Kamran, Nakano Yasutaka, Lequin Maarten H, Tiddens Harm A W M, Aldrich John, Coxson Harvey O, Sin Don D
Department of Pediatric Pulmonology and Allergology, Erasmus MC-Sophia Children's Hospital, Dr Molewaterplein 60, 3015 GJ Rotterdam, The Netherlands.
Am J Respir Crit Care Med. 2006 Jan 15;173(2):199-203. doi: 10.1164/rccm.200505-810OC. Epub 2005 Oct 27.
Low-dose radiation from computed tomography (CT) may increase the risk of certain cancers, especially in children.
We sought to estimate the excess all-cause and cancer-specific mortality, which may be associated with repeated CT scanning of patients with cystic fibrosis (CF).
The radiation dose was calculated for a published CF surveillance CT scanning protocol of biennial CT scans, and the risk per scan was estimated using atom-bomb survivor data. A computational model was developed to calculate the excess mortality in a CF cohort associated with radiation from the CT scan and to evaluate the effects of background survival, scanning interval, and level of CT radiation used. The model assumed that there would be no survival benefits associated with repeated surveillance CT scanning.
The average radiation dose for the published CT protocol was 1 mSv. Survival reduction associated with annual scans from age 2 yr until death was approximately 1 mo and 2 yr for CF cohorts, with a median survival of 26 and 50 yr, respectively. Corresponding cumulative cancer mortality was approximately 2 and 13% at age 40 and 65 yr, respectively. Biennial CT scanning reduced all-cause and cumulative cancer mortality by half.
Routine lifelong annual CT scans carry a low risk of radiation-induced mortality in CF. However, as the overall survival increases for patients with CF, the risk of radiation-induced mortality may modestly increase. These data indicate that radiation dose must be considered in routine CT imaging strategies for patients with CF, to ensure that benefits outweigh the risks.
计算机断层扫描（CT）的低剂量辐射可能会增加某些癌症的风险，尤其是在儿童中。
我们试图估算全因死亡率和特定癌症死亡率的增加情况，这可能与囊性纤维化（CF）患者的重复CT扫描有关。
根据已发表的每两年进行一次CT扫描的CF监测CT扫描方案计算辐射剂量，并使用原子弹幸存者数据估算每次扫描的风险。开发了一个计算模型，以计算CF队列中与CT扫描辐射相关的额外死亡率，并评估背景生存率、扫描间隔和所用CT辐射水平的影响。该模型假设重复监测CT扫描不会带来生存益处。
已发表的CT方案的平均辐射剂量为1毫希沃特。对于CF队列，从2岁到死亡每年进行扫描导致的生存减少约为1个月和2年，中位生存期分别为26年和50年。在40岁和65岁时，相应的累积癌症死亡率分别约为2%和13%。每两年进行一次CT扫描可将全因死亡率和累积癌症死亡率降低一半。
CF患者进行终身常规年度CT扫描的辐射诱发死亡风险较低。然而，随着CF患者总体生存率的提高，辐射诱发死亡的风险可能会适度增加。这些数据表明，在CF患者的常规CT成像策略中必须考虑辐射剂量，以确保益处大于风险。
