Very Early Onset of Therapy-Related Acute Myeloid Leukemia with 11q23 Rearrangement Presenting with Unusual PET Findings after R-DA-EPOCH for Primary Mediastinal Large B-Cell Lymphoma

Background: R-DA-EPOCH is an effective regimen for PMLBCL, which permits the omission of consolidative radiotherapy in the majority of patients. Patient: We describe a 27-year-old female patient, who achieved a complete remission after treatment with six cycles of R-DA-EPOCH (up to the final level). At 6 months after the end of treatment, PET/CT revealed an unexpected, diffusely increased (18)FDG uptake by the bone marrow. Simultaneously, pancytopenia with monocytosis was observed. Result: The patient was diagnosed with therapy-related myelodysplastic syndrome, which rapidly evolved into acute myeloid leukemia (t-MDS/AML) with MLL rearrangements. She achieved a complete remission after induction therapy, received an allogenic transplant and remains disease-free 2 years later. Conclusions: The extremely early onset of t-MDS/AML, together with the unexpected PET/CT findings make this case unique and highlights the need for the accurate estimation of the possible dose-dependent risk of t-MDS/AML after R-DA-EPOCH in the real-life setting in patients with PMLBCL.