Daly Corinne, Urbach David R, Stukel Thérèse A, Nathan Paul C, Deitel Wayne, Paszat Lawrence F, Wilton Andrew S, Baxter Nancy N
Department of Surgery, Li Ki Shing Knowledge Institute, St. Michael's Hospital, Toronto, Canada.
Department of Surgery, University Health Network, Toronto, Canada.
BMC Cancer. 2015 Sep 3;15:612. doi: 10.1186/s12885-015-1578-1.
Survivors of young adult malignancies are at risk of accumulated exposures to radiation from repetitive diagnostic imaging. We designed a population-based cohort study to describe patterns of diagnostic imaging and cumulative diagnostic radiation exposure among survivors of young adult cancer during a survivorship time period where surveillance imaging is not typically warranted.
Young adults aged 20-44 diagnosed with invasive malignancy in Ontario from 1992-1999 who lived at least 5 years from diagnosis were identified using the Ontario Cancer Registry and matched 5 to 1 to randomly selected cancer-free persons. We determined receipt of 5 modalities of diagnostic imaging and associated radiation dose received by survivors and controls from years 5-15 after diagnosis or matched referent date through administrative data. Matched pairs were censored six months prior to evidence of recurrence.
20,911 survivors and 104,524 controls had a median of 13.5 years observation. Survivors received all modalities of diagnostic imaging at significantly higher rates than controls. Survivors received CT at a 3.49-fold higher rate (95% Confidence Interval [CI]:3.37, 3.62) than controls in years 5 to 15 after diagnosis. Survivors received a mean radiation dose of 26 miliSieverts solely from diagnostic imaging in the same time period, a 4.57-fold higher dose than matched controls (95% CI: 4.39, 4.81).
Long-term survivors of young adult cancer have a markedly higher rate of diagnostic imaging over time than matched controls, imaging associated with substantial radiation exposure, during a time period when surveillance is not routinely recommended.
青年成人恶性肿瘤幸存者面临因重复诊断性成像而累积辐射暴露的风险。我们设计了一项基于人群的队列研究，以描述在通常无需进行监测成像的生存期间，青年成人癌症幸存者的诊断性成像模式和累积诊断性辐射暴露情况。
利用安大略癌症登记处确定1992年至1999年在安大略省被诊断为侵袭性恶性肿瘤、诊断后至少存活5年的20至44岁青年成人，并以5比1的比例与随机选择的无癌个体进行匹配。通过行政数据，我们确定了幸存者和对照组在诊断或匹配参考日期后5至15年接受的5种诊断性成像方式及相关辐射剂量。在复发证据出现前六个月对匹配对进行截尾。
20,911名幸存者和104,524名对照者的中位观察时间为13.5年。幸存者接受所有诊断性成像方式的比率显著高于对照组。在诊断后的5至15年，幸存者接受CT检查的比率比对照组高3.49倍（95%置信区间[CI]：3.37, 3.62）。在同一时期，幸存者仅从诊断性成像中接受的平均辐射剂量为26毫西弗，比匹配对照组高4.57倍（95% CI：4.39, 4.81）。
青年成人癌症的长期幸存者随着时间推移接受诊断性成像的比率明显高于匹配对照组，且在不常规推荐监测的时期内，成像会带来大量辐射暴露。
