A 66-year-old male presented with
fever and
erythema at our hospital, and leukoerythroblastosis,
anemia,
thrombocytopenia, and multiple low-density lesions in the moderately
enlarged spleen were detected. Skin tissue revealed CD8+ T cells with the expression of cytotoxic molecule markers involving fat lobules, and subcutaneous
panniculitis T-cell lymphoma (SPTCL) was diagnosed. The bone marrow displayed no infiltration of lymphoid
tumor cells, but
hyperplasia of granulocytes and megakaryocytes with grade 2 stromal
fibrosis. In addition, the bone marrow exhibited diffuse 18F-fluorodeoxyglucose (FDG) accumulation on FDG positron-emission tomography/computed tomography (FDG-PET/CT). Although
chemotherapy improved SPTCL, the patient died from
leukocytosis with leukoerythroblastosis. We obtained negative results for the JAK2 V617F mutation, and CD34+ cells were elevated in the bone marrow compared with the levels at initial examination. The final diagnosis was concurrent
myelodysplastic syndrome (MDS) with
fibrosis and SPTCL. This report highlights that it is essential to consider MDS or other myeloproliferative
neoplasms (MPN) as possible complications when
malignant lymphoma complicates
myelofibrosis in the absence of bone marrow infiltration of
lymphoma cells. Perhaps, the assessment of clonal markers of MPN and FDG accumulation patterns in the bone marrow by FDG-PET/CT could enable differentiation.