Extramedullary T-lymphoblastic Crisis in a Myelodysplastic/Myeloproliferative Neoplasm with a t(12;22)/MN1::ETV6...

Area of Science:

• Hematology
• Oncology
• Genetics

Background:

• Myelodysplastic/myeloproliferative neoplasms (MDS/MPN) are a heterogeneous group of clonal hematopoietic stem cell disorders.
• Recurrent genetic abnormalities are crucial for subclassification and prognostication of MDS/MPN.
• Chromosomal translocations involving MN1 and ETV6 genes are rare but recurrent in myeloid neoplasms.

Observation:

• A patient with MDS/MPN and neutrophilia developed an extramedullary T-lymphoblastic crisis.
• The sole cytogenetic abnormality identified was the t(12;22)(p13;q12) translocation.
• This presentation shares features with myeloid/lymphoid neoplasms with eosinophilia.

Findings:

• The T-lymphoblastic crisis was refractory to chemotherapy, with allogeneic stem cell transplantation being the only curative option.
• This specific clinical presentation associated with the t(12;22) translocation has not been previously reported.
• The findings support the hypothesis of a neoplastic process originating from an early, uncommitted hematopoietic precursor cell.

Implications:

• This case underscores the importance of comprehensive molecular characterization for accurate classification and prognostic assessment of MDS/MPN.
• It highlights the potential for diverse clinical manifestations, including lymphoid crisis, in MDS/MPN.
• The study emphasizes the need for tailored treatment strategies, potentially including stem cell transplantation, for refractory cases.