Division of Haematology/Oncology, Department of Pediatrics, The Hospital for Sick Children, Toronto, Ontario, Canada.
Pediatr Blood Cancer. 2010 Sep;55(3):407-13. doi: 10.1002/pbc.22575.
Despite concerns regarding ionizing radiation exposures from diagnostic imaging procedures in pediatric patients, many are deemed unavoidable or even mandated by treatment protocols. A prior review at our institution found patients with lymphoma had a higher median cumulative radiation exposure (191 mSv) versus other oncology subgroups (61 mSv).
Estimations of cumulative diagnostic radiation exposures were tabulated for 5 years from the first diagnostic scan for 30 consecutive lymphoma patients diagnosed in 2001. Each individual imaging procedure was reviewed and classified as protocol mandated or discretionary (for disease surveillance, good patient care or radiologist request).
Almost all patients (28/29) received chemotherapy; one had surgery only. Individual cumulative radiation exposures ranged from 10 to 642 mSv. Over 5 years, 690 procedures were performed; 303 (44%) X-rays, 203 (29%) CTs, 157 (23%) radionucleotide, and 27 (4%) interventional procedures. Of these, 238 (34%) were protocol required and 452 (66%) discretionary (224 as part of good patient care for a co-morbid illness and 228 for evaluation of possible disease progression/surveillance). A total of 86/217 (40%) studies (including 43 CTs and 38 radionucleotide scans) were performed when the recurrence risk was low (>2 years off therapy).
The majority of ionizing radiation procedures in this lymphoma cohort were discretionary. Given the excellent outcome of this group and the long-term risks; rational use of discretionary surveillance procedures is necessary. Guidelines for the appropriate use of surveillance imaging based on probability of risk recurrence must be developed in order to minimize ionizing radiation exposure.
尽管儿童患者的诊断性影像学检查存在电离辐射暴露问题，但许多检查仍被认为是不可避免的，甚至是治疗方案所必需的。我们机构之前的一项审查发现，患有淋巴瘤的患者的累积辐射暴露中位数（191mSv）高于其他肿瘤亚组（61mSv）。
对 2001 年连续诊断的 30 例淋巴瘤患者的首次诊断性扫描后 5 年内的累积诊断性辐射暴露进行了估算。回顾了每个单独的影像学检查程序，并分为协议规定的和自由选择的（用于疾病监测、良好的患者护理或放射科医生的要求）。
几乎所有患者（28/29）均接受了化疗；1 例仅接受了手术。个体累积辐射暴露量从 10 到 642mSv 不等。在 5 年内，共进行了 690 次检查；303 次 X 射线（44%）、203 次 CT（29%）、157 次放射性核素（23%）和 27 次介入性操作（4%）。其中，238 次（34%）为协议规定的，452 次（66%）为自由选择的（224 次是为合并疾病的良好患者护理而进行的，228 次是为评估可能的疾病进展/监测而进行的）。在复发风险较低（治疗后 2 年以上）时，共进行了 86/217 项研究（包括 43 次 CT 和 38 次放射性核素扫描）。
该淋巴瘤队列中的大多数电离辐射检查是自由选择的。鉴于该组患者的良好预后和长期风险，有必要合理使用自由选择的监测程序。为了尽量减少电离辐射暴露，必须制定基于风险复发概率的适当监测成像指南。
