Bahmanyar S, Montgomery S M, Hillert J, Ekbom A, Olsson T
Clinical Epidemiology Unit, Department of Medicine, Karolinska Institutet, Karolinska Hospital, SE-171 76 Stockholm, Sweden.
Neurology. 2009 Mar 31;72(13):1170-7. doi: 10.1212/01.wnl.0000345366.10455.62.
We investigated cancer risk among patients with multiple sclerosis (MS) and whether variation by age at MS diagnosis helps to elucidate mechanisms underlying the previously reported reduced cancer risk. We also studied cancer risk among parents to ascertain if MS susceptibility genes may confer protection against cancer in relatives.
Cox proportional hazards regression, adjusted for age, sex, area, and socioeconomic index, estimated cancer risk among 20,276 patients with MS and 203,951 individuals without MS, using Swedish general population register data. Similar analyses were conducted among 11,284 fathers and 12,006 mothers of patients with MS, compared with 123,158 fathers and 129,409 mothers of controls.
With an average of 35 years of follow-up, there was a decreased overall cancer risk among patients with MS (hazard ratio = 0.91, 0.87-0.95). Increased risks were observed for brain tumors (1.44, 1.21-1.72) and urinary organ cancer (1.27, 1.05-1.53). Parents of patients with MS did not have a notably increased or decreased overall cancer risk.
The reduction in cancer risk in patients with multiple sclerosis (MS) may result from behavioral change, treatment, or we speculate that some immunologic characteristics of MS disease activity improve antitumor surveillance. The lack of association among parents indicates that a simple inherited characteristic is unlikely to explain the reduced cancer risk among patients with MS. MS is associated with increased risk for some cancers, such as of urinary organs and brain tumors (although surveillance bias may be responsible).
我们调查了多发性硬化症（MS）患者的癌症风险，以及MS诊断时年龄的差异是否有助于阐明先前报道的癌症风险降低的潜在机制。我们还研究了患者父母的癌症风险，以确定MS易感基因是否可能为亲属提供抗癌保护。
利用瑞典总人口登记数据，通过对年龄、性别、地区和社会经济指数进行调整的Cox比例风险回归，估计了20276例MS患者和203951例非MS个体的癌症风险。对11284例MS患者的父亲和12006例母亲进行了类似分析，并与123158例对照的父亲和129409例母亲进行了比较。
平均随访35年，MS患者的总体癌症风险降低（风险比=0.91，0.87-0.95）。脑肿瘤（1.44，1.21-1.72）和泌尿器官癌（1.27，1.05-1.53）的风险增加。MS患者的父母总体癌症风险没有显著增加或降低。
多发性硬化症（MS）患者癌症风险的降低可能是由于行为改变、治疗，或者我们推测MS疾病活动的一些免疫特征改善了抗肿瘤监测。父母之间缺乏关联表明，简单的遗传特征不太可能解释MS患者癌症风险的降低。MS与某些癌症的风险增加有关，如泌尿器官癌和脑肿瘤（尽管监测偏差可能是原因）。
