An Adult Patient with Early Pre-B Acute Lymphoblastic Leukemia with t(12;17)(p13;q21)/ZNF384-TAF15.

This is a case report of a 46-year-old man diagnosed with early pre-B acute lymphoblastic leukemia (ALL), bearing the translocation t(12;17)(p13;q21) as the sole chromosomal abnormality. This is a rare chromosomal abnormality that has been reported in approximately 25 cases worldwide. FISH analysis revealed a rearrangement of ZNF384 (12p13) and TAF15 (17q12) genes, which is usually associated with a pre-B ALL phenotype with co-expression of the myeloid markers CD13 and/or CD33. ZNF384 encodes a zinc finger protein, which acts as a transcription factor, regulating the expression of several matrix metalloproteinases and TAF15 belongs to the FET (FUS, EWS, and TAF15) family, consisting of RNA and DNA-binding proteins. Unlike most of the cases where CD10 expression was absent or weak, in our case CD10 was highly expressed. The prognostic significance of ZNF384/TAF15 fusion is not very clear since several reports support a generally good prognosis, while others support a poor clinical outcome. Our patient was treated with the German multicenter ALL (GMALL) protocol for B-ALL, but experienced a fulminant gram-negative sepsis and eventually died during induction therapy.