Ohan H, Inamdar K, Shen Y, Liu W, Gomez-Gelvez JC, and Ghosh S. Concurrent JAK2 V617F Acute Myeloid Leukemia (AML) and Leukemic non-nodal Mantle Cell Lymphoma (LN-MCL): Case study. Am J Clin Pathol 2022; 158(SUPP 1):S102-S102.
Am J Clin Pathol
Introduction/Objective: We report a unique case of concurrently occurring Acute Myeloid Leukemia (AML) and Leukemic non-nodal Mantle Cell Lymphoma (LN-MCL) in an 86-year-old male. To the best of our knowledge, this is the first report of AML occurring in the background of LN-MCL, with no known history of any malignancy or chemotherapy.
Methods/Case Report: An 86-year old Caucasian male with unremarkable past medical history presented with pancytopenia, fatigue and generalized weakness. Abdominal CT scan was negative for lymphadenopathy or hepatosplenomegaly. Peripheral blood showed 2% blasts with atypical lymphocytes 89%. Bone marrow aspirate showed 30% myeloblasts expressing CD34, CD117, CD13, CD33, HLA-DR and CD56 (dim) by flow cytometry (FC). Lymphocytes accounted for 40% of bone marrow cellularity. FC identified a population of CD5+ kappa restricted clonal B cells 2%, consistent with a concurrent CD5+ B-lymphoproliferative disorder/lymphoma. The bone marrow biopsy was inadequate for further evaluation of the B- cell lymphoma. Chromosomal analysis revealed a normal male karyotype. FISH analysis was positive for t(11:14) CCND1::IGH rearrangement (in 3.5% of interphase cells) supporting involvement by MCL. Myeloid panel next generation sequencing (51 genes) was positive for JAK2 V617F (VAF, 38%) and ASXL1 P920Tfs*4 (VAF, 22%) variants.
Conclusion: Concurrent presence of LN-MCL and AML as seen in our patient in the absence of prior history of malignancy or chemotherapy is rare. Presence of JAK2V617F mutation in de-novo AML is extremely rare (<5%). There is no prior history of myeloproliferative neoplasm (MPN) or CBC data to suggest that this may have progressed from an MPN. While the absence of lymphadenopathy suggests that the CD5+ B-LPD likely represents LN-MCL, it is also likely that the CD5+, IgH/CCND1 rearranged B-cells may represent prior undetected circulating cells without overt LN-MCL development, similar to those reported in otherwise healthy individuals. It is unclear but tempting to speculate that the two co-occurring hematologic malignancies may have a common cell of origin.