Treatment of rheumatoid arthritis after regression of lymphoproliferative disorders in patients treated with methotrexate: A retrospective, multi-center descriptive study: Comment on the article by Nakano K etal.

Abstract

I read the paper by Nakano et al. with great interest [1]. I consider it to be a very important paper, as it identifies the optimal treatment for rheumatoid arthritis after the regression of lymphoproliferative disorders (LPDs). However, some problems remain to be solved in order to better understand this paper. The authors state in the Relapse of LPD section of the text that the rate of LPD relapse tended to be lower in the persistent-LPD group that resumed biological disease-modifying antirheumatic drugs (bDMARDs) (page 44, right panel, line 21). On the other hand, looking at Supplementary Table S2, the relapse rates of regressive-LPD with resumed bDMARDs, regressive-LPD without resumed bDMARDs, persistent-LPD with resumed bDMARDs, and persistent-LPD without resumed bDMARDs were 19.6%, 14.9%, 54.5%, and 29.3%, respectively. In other words, it was not persistent-LPD with resumed bDMARDs that showed the lowest risk of LPD relapse among these four groups, but rather regressive-LPD without resumed bDMARDs. It is difficult to see how the data in this Supplementary Table S2 and the results shown in Figure 2b could be consistent with each other. It is my opinion that the authors need to show some of the causes underlying this inconsistency.