Chidamide maintenance after allogeneic hematopoietic stem cell transplantation in mycosis fungoides: A case report.

Primary cutaneous T-cell lymphoma (CTCL) comprises a group of rare, aggressive non-Hodgkin lymphomas, of which mycosis fungoides (MF) and Sézary syndrome are the most common subtypes. In the absence of a universally accepted standard of care for advanced stages, allogeneic hematopoietic stem cell transplantation (allo-HSCT) offers curative potential; however, post-transplant relapses remains the principle cause of treatment failure, making effective maintenance strategies crucial. This report describes the case of a young woman with stage IVA MF who, following failure of multiple conventional therapies, underwent haploidentical allo-HSCT and initiated chidamide maintenance upon achieving complete remission. This approach successfully consolidated remission for 10 months; however, the patient relapsed at 11 months post-transplant and ultimately died of neutropenic septic shock. This case suggests that post-transplant chidamide maintenance may have value in delaying disease progression in advanced MF; however, treatment-related toxicities and the risk of relapse remain significant clinical challenges requiring further investigation.