del(5q) in acute lymphoblastic leukemia with biphenotypic and early progenitor phenotype

An uncommon case of an adult with del(5)(q) in acute lymphoblastic leukemia

Del(5)(q) is a common chromosomal abnormality with favourable prognosis in Myelodysplastic Syndrome (MDS) and Acute myeloid leukemia (AML). However, del(5)(q) is also seen rarely in Acute lymphoblastic leukemia (ALL) and its significance remains poorly understood. We present here, a case report of diagnosis of an adult 75 year old patient of ALL with a cytogenetic abnormality of del(5)(q32). His clinical features, morphology and immunophenotyping findings were suggestive of T-ALL. Relevant literature has been reviewed and discussed.

Cytogenetic profile of acute lymphocytic leukemia patients: report of a novel translocation t(4;13) (q21 x 3; q35) from an Indian population

Acute lymphocytic leukemia (ALL) is a malignant neoplasm characterized by clonal proliferation, decreased apoptosis and accumulation of immature lymphoid cells in the bone marrow as well as the peripheral blood. The aim of this study was to determine the overall cytogenetic profile of Indian ALL patients along with their frequency and distribution pattern. A total of 75 ALL subjects were included in the study. The major outcome of the work was identification of a novel translocation t(4;13) (q21 x 3;q35) that has not yet been reported. In addition, a few rare chromosomal aberrations such as t(4;16) (p16;q12 x 2) and t(7;10)(q36;q21 x 2) were also detected. Overall, of 75 cases, 67 (89 x 33%) were successfully karyotyped. Normal and abnormal karyotypes were seen in 38 (56 x 7%) and 29 (43 x 3%) cases respectively. Various other abnormalities were hyperdiploidy (20 x 68%), hypodiploidy (10 x 34%), t(8;14) (3 x 44%), t(9;22) (6 x 9%), t(4;16) (3 x 44%), t(7;10) (3 x 44%) and gain of chromosome 8, 13, 16, and 22 was seen in one case each (3 x 44%). Deletions in chromosome 5, 9 and 11 were found to be 3 x 44, 6 x 89 and 6 x 89% respectively, while complex and other aberrations were detected in 3 x 44 and 13 x 8% cases. Finally, we conclude that cytogenetic analysis has an important role in routine genetic diagnostic workup and management of ALL patients.

Acute leukemia with B-lymphoid and myeloid differentiation associated with an inv(5)(q13q33) in an adult patient

A paracentric inversion in the long arm of chromosome 5, inv(5)(q13q33), was found as a clonal abnormality in a patient with a treatment-resistant biphenotypic acute leukemia with B-lymphoid and myeloid differentiation. This cytogenetic aberration has not been reported previously in biphenotypic acute leukemia, although rearrangements of chromosome bands q13 and q33 have been implicated in the development of several hematologic malignancies. The presence of this aberration as the sole chromosomal abnormality suggests an important role in the pathogenesis of biphenotypic acute leukemia.

Cytogenetics in acute leukemia

Cytogenetic analyses in acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) have revealed a great number of non-random chromosome abnormalities. In many instances, molecular studies of these abnormalities identified specific genes implicated in the process of leukemogenesis. The more common chromosome aberrations have been associated with specific laboratory and clinical characteristics, and are now being used as diagnostic and prognostic markers guiding the clinician in selecting the most effective therapies. Specific chromosome aberrations and their molecular counterparts have been included in the World Health Organization classification of hematologic malignancies, and together with morphology, immunophenotype and clinical features are used to define distinct disease entities. However, the prognostic importance of less frequent recurrent aberrations in AML and ALL, both primary and secondary, is still to be determined. This review summarizes current views on clinical relevance of major cytogenetic findings in adult AML and ALL.

New complex t(2;11;17)(p21;q23;q11), a variant form of t(2;11), associated with del(5)(q23q32) in myelodysplastic syndrome-derived acute myeloblastic leukemia

The t(2;11)(p21;q23) is a rare recurrent aberration observed in myelodysplastic syndrome (MDS) and acute myeloblastic leukemia (AML). It has been suggested that t(2;11) is specifically associated with a deletion of the long arm of chromosome 5 (5q). A 63-year-old man was initially diagnosed as AML with del(5)(q23q32) as a sole abnormality. At relapse, t(2;11;17)(p21;q23;q11) in association with del(5q) appeared in 14 of 20 cells by G-banding. Spectral karyotyping confirmed three derivative chromosomes, der(11)t(2;11), der(17)t(11;17), and der(2)t(2;17). Fluorescence in situ hybridization analysis with a probe for MLL demonstrated that the breakpoint at 11q23 was telomeric to the MLL gene. Nine of 10 reported cases with t(2;11) and del(5q) had MDS including 5q- syndrome and four of them evolved to AML, as observed in the present case. Our results indicated that t(2;11;17) was a secondary genetic change, which appeared during disease progression after del(5q) was observed. Furthermore, considering another reported case, the MLL gene seems to be not involved in the pathogenesis of MDS/AML with t(2;11) and del(5q).

New recurring cytogenetic abnormalities and association of blast cell karyotypes with prognosis in childhood T-cell acute lymphoblastic leukemia: a Pediatric Oncology Group report of 343 cases

To further define the cytogenetic differences between B-cell lineage (B-lineage) acute lymphoblastic leukemia (ALL) and T-cell lineage ALL (T-ALL) and to determine the prognostic value of cytogenetics in childhood T-ALL, the blast cell karyotypes of 343 cases of pediatric T-ALL, the largest series reported to date, were evaluated. Cytogenetics were performed in a single central laboratory, and the children were treated using a single Pediatric Oncology Group protocol. Clear differences between the karyotypic characteristics of B-lineage ALL and T-ALL were confirmed. This study suggests that there may be survival differences associated with some T-ALL blast cell karyotypes. Better survival is associated with only normal karyotypes and with t(10;14) (translocation of chromosomes 10 and 14); worse survival is associated with the presence of any derivative chromosome. Two new recurring chromosome aberrations previously not reported in T-ALL were found: del(1)(p22) and t(8;12)(q13;p13). Ten aberrations found in this series, which were reported only once previously in T-ALL, can now be considered recurring abnormalities in T-ALL. All 12 of these new recurring aberrations are targets for discovery and characterization of new genes that are important in T-cell development and leukemogenesis.

New recurring cytogenetic abnormalities and association of blast cell karyotypes with prognosis in childhood T-cell acute lymphoblastic leukemia: a Pediatric Oncology Group report of 343 cases

To further define the cytogenetic differences between B-cell lineage (B-lineage) acute lymphoblastic leukemia (ALL) and T-cell lineage ALL (T-ALL) and to determine the prognostic value of cytogenetics in childhood T-ALL, the blast cell karyotypes of 343 cases of pediatric T-ALL, the largest series reported to date, were evaluated. Cytogenetics were performed in a single central laboratory, and the children were treated using a single Pediatric Oncology Group protocol. Clear differences between the karyotypic characteristics of B-lineage ALL and T-ALL were confirmed. This study suggests that there may be survival differences associated with some T-ALL blast cell karyotypes. Better survival is associated with only normal karyotypes and with t(10;14) (translocation of chromosomes 10 and 14); worse survival is associated with the presence of any derivative chromosome. Two new recurring chromosome aberrations previously not reported in T-ALL were found: del(1)(p22) and t(8;12)(q13;p13). Ten aberrations found in this series, which were reported only once previously in T-ALL, can now be considered recurring abnormalities in T-ALL. All 12 of these new recurring aberrations are targets for discovery and characterization of new genes that are important in T-cell development and leukemogenesis.

5q- anomaly preceding acute myeloblastic leukemia with 53 chromosomes without chromosome 5 abnormality

Partial deletion of the long arm of chromosome 5 (5q-) was found in a patient with a myeloid disorder. After treatment, hematologic parameters became normal, but acute myeloblastic leukemia occurred after 58 months. At that time, cytogenetic studies showed the presence of an abnormal clone with 53 chromosomes and without 5q-. This exceptional case suggests that the 5q- abnormality may precede the occurrence of an acute leukemia in favoring the appearance of unrelated malignant clones.