Cancer and Chronic Conditions (C3) Research Group, Department of Public Health, University of Otago, Wellington, New Zealand.
Department of Public Health, University of Otago, Wellington, New Zealand.
BMC Cancer. 2018 Feb 14;18(1):189. doi: 10.1186/s12885-018-4093-3.
Physical activity has been implicated as a risk factor in the development of testicular cancer (TC), but the relationship remains controversial. This systematic review pooled available evidence regarding this association.
Using Boolean search terms and following PRISMA guidelines, we examined the risk of TC across three categories of exposure: intensity (i.e. comparison of risk between those previously exposed to high, moderate and low levels of physical activity); dose-response (i.e. whether risk of TC increases or decreases with increasing exposure to physical activity); and the role of timing of physical activity (i.e. during early childhood or adolescence).
Thirteen studies (11 case-control studies, 2 cohort studies) were included in the review. While some studies have reported a strong protective effect of high levels of physical activity on risk of TC, others have reported either no relationship or a weak direct association; and while a dose-response relationship has been identified across several studies, this relationship has been observed in both directions. Similarly conflicting results exist in terms of individual types of activity and the lifecourse timing of the physical activity. Reasons for this inconsistency may include the absence of any association, heterogeneous assessment of physical activity, misclassification bias and difference in sample sizes.
On balance, there is presently no strong evidence of an association between physical activity and risk of subsequent TC. This review highlights key areas for future investigation that may clarify any association between physical activity and risk of testicular cancer.
体力活动已被认为是睾丸癌 (TC) 发展的一个风险因素，但这种关系仍存在争议。本系统评价汇集了关于这种关联的现有证据。
使用布尔搜索词并遵循 PRISMA 指南，我们检查了暴露于三种暴露类别下的 TC 风险：强度（即比较以前暴露于高、中、低体力活动水平的人之间的风险）；剂量反应（即 TC 的风险是否随体力活动的增加而增加或减少）；体力活动时机的作用（即儿童期或青春期早期）。
共有 13 项研究（11 项病例对照研究，2 项队列研究）纳入了本综述。虽然一些研究报告了高水平体力活动对 TC 风险的强烈保护作用，但其他研究报告要么没有关系，要么直接关联较弱；虽然已经在几个研究中确定了剂量反应关系，但这种关系在两个方向都存在。同样，在个体活动类型和体力活动的生命历程时间方面也存在相互矛盾的结果。这种不一致的原因可能包括不存在任何关联、体力活动的评估存在异质性、分类偏倚和样本量的差异。
总体而言，目前没有强有力的证据表明体力活动与随后的 TC 风险之间存在关联。本综述强调了未来调查的关键领域，这些领域可能会澄清体力活动与睾丸癌风险之间的任何关联。
