与甲氨蝶呤（MTX）相关的淋巴增生性疾病（MTX-LPDs）是甲氨蝶呤治疗后的免疫缺陷疾病，主要发生在类风湿关节炎患者中。虽然罕见，但已有报道称，在一些接受MTX治疗的银屑病、皮肌炎和皮肤T细胞淋巴瘤（CTCL）患者中也出现了MTX-LPDs。肌肤芽生菌黄色念珠菌病（GMF）是皮肤T细胞淋巴瘤的一种罕见亚型，其中MTX是难治性病例的治疗选择之一。在本文中，我们报告了一例72岁女性患者，在MTX治疗期间还同时发生了表皮增生病毒（EBV）阳性的弥漫性大B细胞淋巴瘤（DLBCL）。根据第5版WHO血液淋巴瘤分类（WHO-HAEM）的定义，目前将该情况归类为“免疫缺陷/失调引起的淋巴瘤”。本文还回顾了已发表的有关CTCL背景下肌肤MTX-LPDs的文献。对于接受长期MTX治疗的CTCL患者出现新的非典型皮肤结节和/或斑块的情况，应考虑到这种实体的存在。 © 2023 Kositkuljorn等人。

Methotrexate-related lymphoproliferative disorders (MTX-LPDs) are immunodeficiency diseases following methotrexate (MTX) administration, mainly occurring in rheumatoid arthritis patients. Although uncommon, MTX-LPDs have been reported in some patients with psoriasis, dermatomyositis, and cutaneous T-cell lymphoma (CTCL) who received MTX. Granulomatous mycosis fungoides (GMF) is a rare subtype of cutaneous T-cell lymphoma, where MTX is one of the treatment options in recalcitrant cases. Herein, we report a case of a 72-year-old female patient with GMF who additionally developed cutaneous Epstein-Barr virus (EBV)-positive diffuse large B-cell lymphoma (DLBCL) during MTX treatment. According to the 5th edition of the WHO classification of Haematolymphoid Tumors (WHO-HAEM), this condition is currently categorized as "lymphoma arising in immunodeficiency/dysregulation". In this article, we also reviewed published literature on cutaneous MTX-LPDs in the setting of CTCL. This entity should be considered in cases of new, atypical skin nodules and/or plaques in CTCL patients receiving long-term MTX treatment.© 2023 Kositkuljorn et al.