Royal H D
Division of Nuclear Medicine, Mallinckrodt Institute of Radiology, St. Louis, Missouri, USA.
Otolaryngol Head Neck Surg. 1996 Nov;115(5):399-402. doi: 10.1177/019459989611500506.
This article discusses the potential carcinogenic effects of radiation exposure from nasopharyngeal radium irradiation exposure and issues to consider when deciding whether to recommend screening for asymptomatic patients who have been treated by nasopharyngeal radium irradiation. The radiation exposure from the radium is primarily the result of gamma-rays, which are very penetrating. beta-Particles would affect only the tissues located within 1 cm of the eustachian tube orifice. On the basis of a quantitative risk assessment, the lifetime risk of brain cancer developing was estimated to be approximately 3 per 1000 persons, and the lifetime risk of a fatal cancer 5.6 per 1000 persons. When the medical benefits of screening asymptomatic patients are assessed, several factors, including the medical risks and benefits and cost-effectiveness of follow-up, should be considered.
本文讨论了鼻咽癌镭照射暴露的辐射致癌潜在影响，以及在决定是否建议对接受过鼻咽癌镭照射治疗的无症状患者进行筛查时需要考虑的问题。镭的辐射暴露主要是γ射线的结果，γ射线具有很强的穿透力。β粒子只会影响咽鼓管开口1厘米范围内的组织。基于定量风险评估，估计患脑癌的终身风险约为每1000人中有3人，患致命癌症的终身风险为每1000人中有5.6人。在评估对无症状患者进行筛查的医疗益处时，应考虑几个因素，包括医疗风险和益处以及后续随访的成本效益。
