The t(1;22) (p13;q13) is nonrandom and restricted to infants with acute megakaryoblastic leukemia: a Pediatric Oncology Group Study

Abstract

We report the nonrandom occurrence and frequency of the t(1;22)(p13;q13) in acute myeloid leukemia (AML) and its close association with the French-American-British M7 subtype of AML in infants (less than 1 year). This chromosomal abnormality occurred in 6 of 252 (2.4%) children and adolescents with AML (6 of 28 infants, 22%; 6 of 18 M7 AML cases overall, 33%; and 6 of 6 M7 cases in infants). Infants with AML of M7 subtype and the t(1;22) often presented with prominent abdominal masses. Two of these infants were not treated and died early. Three of four treated infants entered complete remission with therapy for AML; the remaining infant died of hemorrhage on day 8. Of the three infants who entered remission, only one remains alive and disease free at 5+ months. The other two infants relapsed in the bone marrow at 5 and 2 months from the start of therapy, respectively. We conclude that M7 AML with the t(1;22) usually presents in infants with extensive infiltration of abdominal organs by leukemic cells and may confer a poor prognosis despite intensive AML-directed treatment. Identification of this nonrandom translocation exclusively in infants with acute megakaryoblastic leukemia (AMkL) implies that it may serve as an additional diagnostic marker for this disease and links it to the pathogenesis of AMkL in infants.

Biology, clinical, and hematologic features of acute megakaryoblastic leukemia in children

“…In the present study in which we used a systematic approach to identify the presence of megakaryoblasts with a panel of MoAbs against platelet specific markers in all cases of newly diagnosed AL attending the Hematology Department at the INP between January 1, 1990, and July 31, 2002, we found an 19.1% incidence of AMKL. Our data and those of Ruiz-Argüelles et al [28] suggest that the incidence of FAB AML-M7 might be higher in Mexico, than those reported in Caucasian white pediatric population in western countries [14][15][16][17]. Twenty-four percent of the cases in our study occurred in infants 2 years old or younger, and this included 20.7% of non-DS children (6 cases) and one patient (3.45%) with DS, and more than 40% of the cases occurred in children 41 months of age or younger.…”

“…Within the last 10 years with specific criteria for diagnosis, the clinicopathologic features of AMKL have been defined and the incidence has been estimated to be 4-7% of pediatric AML in large Cooperative Group studies in developed countries [14][15][16][17], although higher incidence rates (10-15%) have been reported from single institutions [13,[18][19][20][21]. Based on the number of single case reports or of small series that included a limited number of cases, the incidence of AMKL appears to be higher in children than in adults [13,[19][20][21][22][23][24][25][26][27].…”

Karyotype evolution in a patient with down syndrome and acute leukemia following a congenital leukemoid reaction

“…The trisomy 12 observed in this karyotype is most commonly found in B-lineage chronic lymphocytic leukemia and occurs almost exclusively in middle-aged and elderly patients. Trisomies for chromosomes 6,19, and 22 have all been reported in other cases of acute leukemia associated with Down syndrome [21].…”

Clinicopathological features of acute megakaryoblastic leukaemia: Relationship between fibrosis and platelet‐derived growth factor

“…With regard to chromosomal analysis of AMGL, previous studies reported that in children and particularly infants under 1 year of age, there may be an association with a t(1;22)(p13;q13). 1,33 In addition, the c-sis gene, which encodes the B chain of PDGF, 34 is on 22q13. 35 Others demonstrated an association between AMGL and abnormalities of -5, -7, -5q and -7q.…”