Generation of the NUP98-TOP1 fusion transcript by the t(11;20) (p15;q11) in a case of acute monocytic leukemia

A rare chromosomal translocation, (11;20)(p15;q11), was detected in a 29-year-old male patient diagnosed with acute monocytic leukemia (AMoL) according to the French–American–British classification criteria. Whole chromosome painting analysis with paints for chromosomes 11 and 20 confirmed the result of conventional cytogenetic analysis. Reverse transcriptase polymerase chain reaction revealed the NUP98-TOP1 fusion transcript. To our knowledge, this is the second report of the translocation involving NUP98 and TOP1 genes in AMoL. On reviewing the literature, we suggest that t(11;20)(p15;q11) is associated with myelocytic disorders rather than lymphocytic proliferative diseases.