We analyzed 12 MLL/ENL positive ALL patients consecutively diagnosed between 1999 and 2009. The MLL/ENL fusion was identified in 4/150 (2.6%), 8/993 (0.8%), and 0/70 of pediatric, adult, and elderly patients, respectively. Eight patients had a WBC count >50 x 109/L. Ten cases had an evaluable immunophenotyping. A B or T precursor ALL occurred in 7 and 3 patients, respectively. Eleven/12 patients (92%) achieved CR. At 48 months, overall survival and event-free survival rates were 73.3% and 67%, respectively. At CR, a parallel RT-PCR evaluation of the MLL/ENL expression was available in 5 cases. Of these latter, 2 tested MLL/ENL-negative and 3 positive. The minimal residual disease molecular monitoring showed that MLL/ENL status did not correlate with outcome. In fact, all the 2 PCR-negative and 1 of the 3 PCR-positive cases relapsed. Further, a MLL/ENL expression, not preceding a relapse, was detected several times during the follow-up of five long-survivors. In conclusion, also in adults, the MLL/ENL fusion identifies a rare leukemic entity with a favorable prognosis. The observed inconsistency between the clinical cure and the presence of detectable MLL/ENL transcript suggests the existence of a MLL/ENL-expressing preleukemia stem cells, similar to what demonstrated for the AML1/ETO-positive leukemia setting. Am. J. Hematol. 2011. (c) 2011 Wiley-Liss, Inc.
Clinical outcome and monitoring of minimal residual disease in patients with acute lymphoblastic leukemia expressing the MLL/ENL fusion gene / Elia, Leopoldo; Grammatico, Sara; Francesca, Paoloni; Vignetti, Marco; Angela, Rago; Cenfra, Natalia; Sergio, Mecarocci; Marco, Mancini; Matteo, Luciani; Francesco Di, Raimondo; Giovanni, Cazzaniga; Mabel, Matarazzo; Maria Luisa, Moleti; Lidia, Santoro; Gianluca, Gaidano; Foa, Roberto; Mandelli, Franco; Cimino, Giuseppe. - In: AMERICAN JOURNAL OF HEMATOLOGY. - ISSN 0361-8609. - 86:12(2011), pp. 993-997. [10.1002/ajh.22161]
Clinical outcome and monitoring of minimal residual disease in patients with acute lymphoblastic leukemia expressing the MLL/ENL fusion gene
ELIA, Leopoldo;GRAMMATICO, SARA;VIGNETTI, Marco;CENFRA, NATALIA;FOA, Roberto;MANDELLI, Franco;CIMINO, Giuseppe
2011
Abstract
We analyzed 12 MLL/ENL positive ALL patients consecutively diagnosed between 1999 and 2009. The MLL/ENL fusion was identified in 4/150 (2.6%), 8/993 (0.8%), and 0/70 of pediatric, adult, and elderly patients, respectively. Eight patients had a WBC count >50 x 109/L. Ten cases had an evaluable immunophenotyping. A B or T precursor ALL occurred in 7 and 3 patients, respectively. Eleven/12 patients (92%) achieved CR. At 48 months, overall survival and event-free survival rates were 73.3% and 67%, respectively. At CR, a parallel RT-PCR evaluation of the MLL/ENL expression was available in 5 cases. Of these latter, 2 tested MLL/ENL-negative and 3 positive. The minimal residual disease molecular monitoring showed that MLL/ENL status did not correlate with outcome. In fact, all the 2 PCR-negative and 1 of the 3 PCR-positive cases relapsed. Further, a MLL/ENL expression, not preceding a relapse, was detected several times during the follow-up of five long-survivors. In conclusion, also in adults, the MLL/ENL fusion identifies a rare leukemic entity with a favorable prognosis. The observed inconsistency between the clinical cure and the presence of detectable MLL/ENL transcript suggests the existence of a MLL/ENL-expressing preleukemia stem cells, similar to what demonstrated for the AML1/ETO-positive leukemia setting. Am. J. Hematol. 2011. (c) 2011 Wiley-Liss, Inc.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.