Myeloid/Lymphoid Neoplasm with FGFR1 Rearrangement Presenting with Polycythemia Vera and T-cell Acute Lymphoblastic...

Area of Science:

• Hematology
• Oncology
• Genetics

Background:

• Myeloid/lymphoid neoplasms with fibroblast growth factor 1 rearrangements (MLN-FGFR1) are rare hematologic malignancies.
• Diagnosis often requires integration of morphology, immunophenotype, cytogenetics, and molecular findings.

Observation:

• A 69-year-old woman presented with adenopathy and a history of polycythemia vera.
• Lymph node biopsy revealed T-cell acute lymphoblastic lymphoma (T-ALL) with an FGFR1 rearrangement (t(8;13)).
• Bone marrow biopsy showed trilineage hyperplasia and confirmed MLN-FGFR1, alongside an ASXL1 frameshift mutation and variants of unknown significance in HDAC4 and CHEK2.

Findings:

• This is the second reported case of MLN-FGFR1 with an ASXL1 mutation.
• This is the first reported case of MLN-FGFR1 with co-occurring HDAC4 and CHEK2 variants.
• The patient experienced rapid clinical deterioration and death despite initial treatment response.

Implications:

• This case expands the known molecular landscape of MLN-FGFR1.
• Identifying novel genetic alterations may inform future therapeutic strategies for rare hematologic neoplasms.
• Further research is needed to understand the role of ASXL1, HDAC4, and CHEK2 in MLN-FGFR1 pathogenesis.