Sodickson Aaron, Baeyens Pieter F, Andriole Katherine P, Prevedello Luciano M, Nawfel Richard D, Hanson Richard, Khorasani Ramin
Department of Radiology and Center for Evidence Based Imaging, Brigham and Women's Hospital, 75 Francis St, Boston, MA 02115, USA.
Radiology. 2009 Apr;251(1):175-84. doi: 10.1148/radiol.2511081296.
To estimate cumulative radiation exposure and lifetime attributable risk (LAR) of radiation-induced cancer from computed tomographic (CT) scanning of adult patients at a tertiary care academic medical center.
This HIPAA-compliant study was approved by the institutional review board with waiver of informed consent. The cohort comprised 31,462 patients who underwent diagnostic CT in 2007 and had undergone 190,712 CT examinations over the prior 22 years. Each patient's cumulative CT radiation exposure was estimated by summing typical CT effective doses, and the Biological Effects of Ionizing Radiation (BEIR) VII methodology was used to estimate LAR on the basis of sex and age at each exposure. Billing ICD9 codes and electronic order entry information were used to stratify patients with LAR greater than 1%.
Thirty-three percent of patients underwent five or more lifetime CT examinations, and 5% underwent between 22 and 132 examinations. Fifteen percent received estimated cumulative effective doses of more than 100 mSv, and 4% received between 250 and 1375 mSv. Associated LAR had mean and maximum values of 0.3% and 12% for cancer incidence and 0.2% and 6.8% for cancer mortality, respectively. CT exposures were estimated to produce 0.7% of total expected baseline cancer incidence and 1% of total cancer mortality. Seven percent of the cohort had estimated LAR greater than 1%, of which 40% had either no malignancy history or a cancer history without evidence of residual disease.
Cumulative CT radiation exposure added incrementally to baseline cancer risk in the cohort. While most patients accrue low radiation-induced cancer risks, a subgroup is potentially at higher risk due to recurrent CT imaging.
评估在一家三级医疗学术中心，成年患者进行计算机断层扫描（CT）时的累积辐射暴露以及辐射诱发癌症的终生归因风险（LAR）。
这项符合健康保险流通与责任法案（HIPAA）的研究经机构审查委员会批准，豁免了知情同意。该队列包括2007年接受诊断性CT检查的31462名患者，他们在之前22年里共接受了190712次CT检查。通过累加典型CT有效剂量来估算每位患者的累积CT辐射暴露，并采用电离辐射生物效应（BEIR）VII方法，根据每次暴露时的性别和年龄估算LAR。使用计费ICD9编码和电子医嘱录入信息，对LAR大于1%的患者进行分层。
33%的患者终生接受了5次或更多次CT检查，5%的患者接受了22至132次检查。15%的患者接受的估算累积有效剂量超过100 mSv，4%的患者接受的剂量在250至1375 mSv之间。相关LAR的癌症发病率均值和最大值分别为0.3%和12%，癌症死亡率均值和最大值分别为0.2%和6.8%。据估计，CT暴露导致的癌症发病率占总预期基线癌症发病率的0.7%，癌症死亡率占总癌症死亡率的1%。该队列中有7%的患者估算LAR大于1%，其中40%没有恶性肿瘤病史或有癌症病史但无残留疾病证据。
累积CT辐射暴露使该队列的基线癌症风险有所增加。虽然大多数患者辐射诱发癌症的风险较低，但由于反复进行CT成像，有一小部分患者可能面临更高风险。
