Bologna C, Picot M C, Jorgensen C, Viu P, Verdier R, Sany J
Service d'Immuno-Rhumatologie, Fédération de Rhumatologie, CHU Lapeyronie, Montpellier, France.
Ann Rheum Dis. 1997 Feb;56(2):97-102. doi: 10.1136/ard.56.2.97.
To report cancer cases in 426 rheumatoid arthritis patients treated with methotrexate, and determine whether there was an increased incidence of cancer compared with patients never treated with methotrexate (rheumatoid controls) and to the whole regional population.
The duration of methotrexate treatment was 37.4 (SD 27.9) months. This population was compared with 420 rheumatoid arthritis controls and with a regional population of 812,344 people. Life table analysis was performed to compare the cancer incidence in the two rheumatoid populations. Adjustment for potentially confounding factors was done. The indirect standardisation methods was used to compare each rheumatoid population with the regional population.
Eight cases of cancer (1.88%; 4.04 cases/1000 person years) were diagnosed in the methotrexate population v six (1.43%; 58.8 cases/1000 person years) in the rheumatoid controls. The life table method showed a higher incidence of cancer in the rheumatoid controls (P = 0.0001). In a multivariate analysis (Cox model), the only significant factor explaining this difference in the cancer incidence was age (P = 0.02). In the regional population there were 6418 new cases of cancer (0.79%; 2.85 cases/1000 person years). By the indirect standardisation method, the ratio of observed cases to expected cases of cancer in each of the rheumatoid populations was not significantly different from 1.
In these eight cases, methotrexate was not found to be responsible for generating cancers. However, because of data regarding lymphomas and methotrexate, and because of the short follow up, especially in the control group, longer prospective studies are warranted.
报告426例接受甲氨蝶呤治疗的类风湿关节炎患者的癌症病例，并确定与从未接受过甲氨蝶呤治疗的患者（类风湿关节炎对照组）及整个地区人群相比，癌症发病率是否有所增加。
甲氨蝶呤治疗的持续时间为37.4（标准差27.9）个月。将该人群与420例类风湿关节炎对照组以及812344人的地区人群进行比较。采用生命表分析比较两个类风湿人群的癌症发病率。对潜在混杂因素进行了调整。采用间接标准化方法将每个类风湿人群与地区人群进行比较。
甲氨蝶呤治疗人群中诊断出8例癌症（1.88%；4.04例/1000人年），而类风湿关节炎对照组中有6例（1.43%；58.8例/1000人年）。生命表法显示类风湿关节炎对照组的癌症发病率更高（P = 0.0001）。在多变量分析（Cox模型）中，解释癌症发病率差异的唯一显著因素是年龄（P = 0.02）。在地区人群中，有6418例新发癌症病例（0.79%；2.85例/1000人年）。通过间接标准化方法，每个类风湿人群中癌症的观察病例数与预期病例数之比与1无显著差异。
在这8例病例中，未发现甲氨蝶呤导致癌症。然而，鉴于有关淋巴瘤和甲氨蝶呤的数据，以及随访时间较短，尤其是在对照组中，有必要进行更长时间的前瞻性研究。
