Relapsed/refractory PBML complicated with failed platelet implantation and mixed infection after allo-HSCT

Rationale: Primary bone marrow lymphoma (PBML) is a rare lymphoma with a poor prognosis, characterized by tumor origin restricted to the bone marrow. Diffuse large B-cell lymphoma (DLBCL) is its most common subtype. Patient concerns: We report a case of a 48-year-old female with refractory non-germinal center DLBCL originating in the bone marrow, accompanied by p53 overexpression, complex karyotype, and hemophagocytic lymphohistiocytosis. Diagnoses: Given the aforementioned adverse genetic features, together with primary platelet poor graft function following allogeneic hematopoietic stem cell transplantation (allo-HSCT), mixed infections, severe acute intestinal graft-versus-host disease (GVHD), and progressive bone marrow stromal necrosis, the patient was diagnosed with multifactorial post-transplant poor graft function with bone marrow microenvironment injury. Interventions: The patient received induction chemotherapy and achieved complete remission, followed by autologous-hematopoietic stem cell transplantation (autoHSCT) for consolidation. After relapse within 3 months, salvage therapy and subsequent allogeneic-hematopoietic stem cell transplantation were performed. Outcomes: Despite intensive supportive therapy, the patient died from massive gastrointestinal bleeding. A literature review identified this as a rare case of PBML with primary platelet Poor graft function and mixed infections post-allo-HSCT. Lessons: This case highlights the treatment challenges and extremely poor prognosis in ultrahigh-risk PBML with adverse genetic features and severe post-transplant complications.