2015 Volume 18 Issue 2 Pages 51-59
Amplification of the MLL gene has been recognized as a recurrent cytogenetic abnormality that occurs in acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). The first case was a 74-year-old man who had a 9-year-long treatment history for hepatocellular carcinoma and concurrent laryngeal cancer. He presented with pancytopenia and his bone marrow picture corresponded to refractory anemia with excess of blasts-2. He died of leukemia progression 80 days after presentation. G-banded karyotype revealed del(7)(q31), −13, two types of ring chromosomes, and one double minute (dmin). The second case was a 68-year-old man who had been treated for bladder, laryngeal, and esophageal cancers for the preceding 12 years. He developed AML with myelodysplasia-related changes and died shortly. Clonally occurring abnormalities were add(2), −5, der(7), der(11), −14, add(15), and a ring chromosome which appeared to be derived from chromosome 11 [r(11)]. Fluorescence in situ hybridization (FISH) using the Vysis LSI MLL dual-color, breakapart rearrangement probe revealed MLL amplification at one of the rings and the dmin in case 1, while in case 2, the gene was duplicated at the atypical banded region of der(11) and amplified at the r(11). del(7q) in case 1 and del(5q) and del(7q) in case 2 were confirmed by FISH, using the respective probes. The clinical features of the two cases corresponded well with those of MLL-amplification-associated AML/MDS. It is likely that the long-lasting cytotoxic treatment for the multiple cancers was responsible for the development of both diseases.
