Cytogenetic Findings in Pediatric T-Lymphoblastic Lymphomas: One Institution’s Experience and a Review of the Literature

Cytogenetic analyses of lymphomas commonly reveal nonrandom chromosomal abnormalities, but there are relatively few reports in childhood lymphoblastic lymphoma (LL). We retrospectively reviewed G-banded karyotypic analyses performed at Arkansas Children’s Hospital between 1990 and 2004. Six children (2 to 20 years old) had LL that presented as mediastinal or cervical masses and had a T-cell immunophenotype and clonal abnormalities. The cytogenetic findings in these 6 patients were as follows: 46,XX,?7,inv(9)(p11q12),der (12)t(7;12)(q11.2;p13),t(16;18)(p13.1;q21),+22 in patient 1; 47,XX,+9,del(9)(q11q22)x2 in patient 2; 72?119, XY,+X,+1,+1, inv(2) (p11q13),?3,+5,+6,+7,+10,?12,?16, ?21,?21,?22,+mar in patient 3; 48,XY,+5,+20,t(7;9) (q32;q34) in patient 4; 47～48,XX,der(10)t(10;14)(q23; q11.2),+12, del(12)(p12)x2, ?14,del(16)(q22q22),+?add (19)(p13.3) in patient 5; and 48～49,XY,+7,+8,t(11;19) (q23;p?13.3),+der(19)t(11;19)[cp20] in patient 6. Eleven chromosome breakpoints in 6 of our patients (7q11, 12p13, 16p13, 18q21, 9q11, 2p11, 2q13, 7q32, and 7q23) have been reported in other patients with acute lymphoblastic leukemia or LL and involved regions containing TEL, ABL, E2A, MLL, and T-cell receptor-α genes. A review of the cytogenetic findings of these and other cases of LL reveals that clonal aberrations are common and most frequently involve T-cell receptor gene regions. The aberrations show some features similar to those of acute lymphoblastic leukemia and are not unique to LL, thus furnishing additional evidence of the equivalence of these two diseases. The cytogenetic features of LL may be helpful in the diagnosis of pediatric lymphomas and undifferentiated neoplasms.     

Acute megakaryoblastic leukemia after transient myeloproliferative disorder with clonal karyotype evolution in a phenotypically normal neonate

We report a case of transient myeloproliferative disorder (TMD) in a neonate without features of Down syndrome (DS) with clonal karyotype evolution, after apparent spontaneous resolution of TMD, but eventually progressing to acute megakaryoblastic leukemia (AMKL). The patient had petechiae, thrombocytopenia, and blastemia. Trisomy 21 with a satellited Y chromosome (Yqs) was found in proliferating blasts. A stimulated peripheral blood culture confirmed the constitutional origin of the Yqs, but did not reveal the presence of any trisomic 21 cell. By the age of 3 months, clonal chromosome evolution in the form of an interstitial deletion of the long-arm of chromosome 13 [del(13)(q13q31)] was detected along with trisomy 21 in unstimulated bone marrow cultures. However, remission was achieved without treatment at the age of 4 months. Trisomy 21 and del(13)(q13q31) were not identified in either cytogenetics or fluorescence in situ hybridization studies at that time. The child was asymptomatic until the age of 20 months when anemia and thrombocytopenia prompted a bone marrow biopsy, revealing changes consistent with AMKL. The remission proceeded by clonal karyotype evolution in a neonate with TMD demonstrates that clonal karyotype evolution does not indicate an immediately progressive disease. However, the development of AMKL after TMD in this case illustrates the increased risk for leukemia in TMD cases, even without DS. The gradual clonal evolution of the blasts in our patient suggests that "multiple hits" oncogenesis applies to TMD progression to acute leukemia.     

Novel translocation in acute megakaryoblastic leukemia (AML-M7)

The authors report a unique translocation in a patient with M7 acute myeloid leukemia and review the literature. A 22-month-old girl without Down syndrome was diagnosed with acute myeloid leukemia, subtype M7 (AML-M7), and died with relapsed disease following bone marrow transplantation. Tumor cells were evaluated using cytogenetics (including spectral karyotyping), immunohistochemistry, and flow cytometry. The patient was found to have a previously unreported complex translocation as follows: 50,XX,der(1)t(1;5)(p36?.1;p15?.1),del(5)(p15?.1), +6,+der(6;7)(?;?),der(7)t(6;7)(?;p22)[2],der(9)t(6;9) (?;p21)t(9;14)(q34;q11.2-q13),+10,t(12;16)(p13;q24),-14[2], del(14)(q13)[2],+der(19)t(1;19)(?;p13.3),+22[cp 4]. AML-M7 in non-Down syndrome patients is a rare disease that requires improved prognostic markers.     

The incidence peaks of the childhood acute leukemias reflect specific cytogenetic aberrations

The correlation between age and karyotype was studied in 1425, 0 to 14.9 years old children who were diagnosed with acute lymphoblastic leukemia (ALL) or acute myeloblastic leukemia. Almost 80% of the non-Down B-cell precursor ALL cases in the 2 to 7 years frequency peak group who had aberrant cytogenetic results had either a high-hyperdiploid clone (51 to 61 chromosomes) or a translocation t(12;21)(p13;q22). Among B-cell precursor ALL cases, high white blood cell counts correlated with earlier age at diagnosis (rS=-0.23; P<0.001) being most evident for 11q23/MLL-aberrations, translocation t(12;21)(p13;q22), and high-hyperdiploidy. Among acute myeloblastic leukemia patients, frequency peaks were found for those with MLL/11q23 rearrangements (peak: first year), Down syndrome (peak: second to third year), or cytogenetic abnormalities other than translocations t(8;21), t(15;17), and inv(16)/t(16;16) (peak: first to third year). The epidemiology of the cytogenetic subsets of acute leukemias questions whether age as a disease-related prognostic parameter has any relevance in childhood leukemia clinical research beyond being a surrogate marker for more important, truly biologic features such as cytogenetic aberrations and white cell count at diagnosis. Further research is needed to explore whether the 2 to 7 years age incidence peak in childhood ALL harbor yet unidentified cytogenetic subsets with the same natural history as the high-hyperdiploid and t(12;21)-positive leukemias.     

Chromosome Abnormalities and Prognosis in Childhood Acute Leukemia

We report here on the leukemic cell karyotypes of 134 children with acute nonlymphocytic leukemia (ANLL) examined at Saitama Children's Medical Center (SCMC), and of 88 children with acute lymphoblastic leukemia (ALL) referred to SCMC. The patients were mainly treated according to the protocol of the Tokyo Children's Cancer Study Group. Of 106 ANLL cases with adequate banding, 18% were normal, 34% had miscellaneous clonal abnormalities, and 48% were classified into known cytogenetic subgroups: t(8;21) (n = 21), 11q23 abnormalities (n=14), -7/del(7q) (n = 6), inv (16)/del(16) (n = 5), and t(15;17) (n = 5). According to the FAB classification, M7 (21.7%) were more frequent than in previous reports because this study included a number of Down's Syndrome patients with M7 morphology. The present study confirmed the well-known association of t(15; 17) with M3, t(8;21) with M2, 11q23 abnormalities with M4 and MS, and inv (16)/del(16) with M4. Patients with t(8;21) or inv (16)/del(16q) ANLL fared no better overall than the entire group. Of 51 ALL cases with adequate banding, 13.7% were normal, and 86.3% were classified into abnormal subgroups: translocation (n=14), hyperdiploidy (>50) (n=13), and miscellaneous abnormalities (n = 17). Cases with hyperdiploidy (>50) were restricted to a common phenotype and fared better overall than the entire group. Patients with translocation were found in all phenotypes, and had a poor prognosis. We concluded that childhood acute leukemia could be subgrouped according to karyotypic patterns, and that patients with translocations had a poor prognosis in ALL as well as ANLL.     

Acquired chromosome rearrangements, including fine interstitial deletions, in a patient with Down syndrome and monoblastic leukemia

A female child with Down syndrome who developed acute monoblastic leukemia is reported. Anemia associated with milk leukopenia was first recognized when the patient was 14 months old. Acute monoblastic leukemia was diagnosed 1 year later; cytogenetic studies were performed on circulating leukemic cells at this time. Analysis of elongated, finely banded chromosomes revealed three structural rearrangements, including two rather subtle interstitial deletions, in addition to trisomy 21 which was representative of the patient's constitutional karyotype. The karyotype of the leukemic cells was 47,XX,+21,t(3;18)(p23;q11.2), del(7)(q31.1q31.3), del(9)(p22p24 or p21p23). The patient received no cytostatic chemotherapy and died 4 months after the diagnosis of acute leukemia was made.     

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

We report the serial cytogenetic study of a patient with Down syndrome who experienced a congenital leukemoid reaction, underwent a spontaneous remission within four months, and subsequently developed acute myeloid leukemia at 16 months. A blood chromosome study to rule out Down syndrome performed at age 24 days, during the leukemoid reaction, revealed a 47,XX,+21 karyotype. The diagnosis of acute leukemia was made at 16 months, at which time a chromosome study, on bone marrow, was performed. This analysis revealed a clonal karyotype of 47,XX,+21,-22,+der (22)t(1;22)(q21;q13) in all but one cell studied. The single apparently nonclonal cell showed a karyotype of 49,XX,+12,-13,-19, +der(19)t(19;?)(q11;?)x2,+21,+22. A third chromosome study at 19 months indicated the original leukemic clone with t(1;22) (q21;q13) had been replaced by the clone represented by the single cell with 49 chromosomes seen in the previous chromosome study. This case of an infant with Down syndrome and acute leukemia illustrated rapid evolution and a transitory nature to clonal chromosome aberrations while retaining AML morphology and course. © 1994 Wiley-Liss, Inc.     

A lineage switch in acute monocytic leukemia. A case report

A case of congenital monocytic leukemia that underwent a lineage switch to acute lymphocytic leukemia (ALL) is described. The original leukemia had typical monocytic features, as evidenced by morphology (FAB M5), cytochemistry (nonspecific esterase) and immunophenotype (My4 positive). Cytogenetic study showed a pseudodiploid clone t(9;11)(p22;q21) that could be interpreted as a variant of the t(9;11)(p22;q23) reported in patients with the M5 type of leukemia. After successful remission induction with single-agent chemotherapy (VM-26) and subsequent sustained remission for 12 months with alternating VM-26 and VP-16-213, lineage switch to ALL (FAB L1) occurred. The presence of both lymphoid and myeloid markers on leukemic cells at lineage switch suggested the biphenotypic character of the patient's ALL. Our observation indicates that a lineage switch can occur from monocytic leukemia to ALL, although most of the cases previously reported have been in the reverse direction. This case emphasizes again the need to carry out careful and comprehensive marker studies to gain insight into the possible prognostic significance and the application of appropriate therapy.     

Successful treatment of a child with T/myeloid acute bilineal leukemia associated with TLX3/BCL11B fusion and 9q deletion

Acute bilineal leukemias are rare and are commonly associated with t(9;22) and MLL abnormalities. Herein, we report a pediatric case of bilineal T/myeloid acute leukemia associated with del (9q)(q13q22) and TLX3/BCL11B fusion due to the cryptic t(5;14)(q35;32). FISH studies confirmed the TLX3/BCL11B fusion in both the myeloid and lymphoid blasts, while the 9q deletion was restricted to the lymphoid component. Optimal therapy for such patients remains controversial and it is not clear if they should be treated with ALL or AML-based chemotherapeutic regimens. Our patient has been in extended remission following ALL-based chemotherapy and a matched unrelated cord blood transplant. Inc.     

儿童Pre-B急性淋巴细胞白血病和急性髓系白血病特异遗传亚型

目的总结儿童急性白血病(AL)特异遗传亚型的发生率和特征,为评估预后提供依据。方法对365例AL患儿进行骨髓染色体核型检测分析白血病细胞的遗传学特点,荧光原位杂交(FISH)检测特异基因及相应位点拷贝数变异。结果 175例前体B急性淋巴细胞白血病(Pre-B ALL)和54例急性髓系白血病(AML)存在特异亚型。在Pre-B ALL中,高超二倍体最常见(33%),t(12;21)/ETV6-RUNX1、t(4;11)/MLL重排、t(9;22)、t(1;19)和iAMP21占比分别为22%、5%、3%、7%和1%。在AML中,MLL重排最常见(18%),其中t(9;11)型占56%;BCR/ABL阳性1例,FISH证实是隐匿核型ins(22;9);t(8;21)、t(15;17)和inv(16)分别占12%、15%和8%。倍体水平显示ALL高超二倍体和AML超二倍体获得染色体方式为非随机性。值得注意的是特异亚型中的变异型和不同附加异常,如额外融合,del(9p),del(12p),dup(1q)和非整倍体等畸变。结论儿童Pre-B ALL和AML中特异遗传亚型的发生率与西方儿童相似,揭示遗传异质性可能有助于预后研究。     

EQUAL FREQUENCY OF TEL/AML1 ACUTE LYMPHOBLASTIC LEUKEMIA IN CHILDREN WITH AND WITHOUT DOWN SYNDROME

Constitutional trisomy 21 is the most prominent predisposing factor to childhood leukemia, whereas the t(12;21)(p13;q22) with its molecular genetic counterpart, the TEL/AML1 fusion gene, is the most common acquired chromosomal rearrangement in childhood B-cell precursor (BCP) acute lymphoblastic leukemia (ALL). Thus, it was somewhat surprising that according to the currently available literature the incidence of TEL/AML1+ BCP ALL is extremely low in patients with Down syndrome (DS). To further investigate this issue in a population-based fashion, the authors retrospectively assessed the number of DS patients with a TEL/AML1+ ALL in two consecutive Austrian ALL multicenter trials. Accordingly, they were able to analyze 8 of 10 individuals with DS and a BCP ALL, including 2 who suffered from a TEL/AML1+ leukemia. Based on this observation we concluded that individuals with a constitutional trisomy 21 may have the similar likelihood to develop a TEL/AML1+ leukemia as BCP ALL patients without this specific predisposing factor.     

Equal frequency of TEL/AML1+ acute lymphoblastic leukemia in children with and without Down syndrome

Constitutional trisomy 21 is the most prominent predisposing factor to childhood leukemia, whereas the t(12;21)(p13;q22) with its molecular genetic counterpart, the TEL/AML1 fusion gene, is the most common acquired chromosomal rearrangement in childhood B-cell precursor (BCP) acute lymphoblastic leukemia (ALL). Thus, it was somewhat surprising that according to the currently available literature the incidence of TEL/AML1+ BCP ALL is extremely low in patients with Down syndrome (DS). To further investigate this issue in a population-based fashion, the authors retrospectively assessed the number of DS patients with a TEL/AML1+ ALL in two consecutive Austrian ALL multicenter trials. Accordingly, they were able to analyze 8 of 10 individuals with DS and a BCP ALL, including 2 who suffered from a TEL/AML1+ leukemia. Based on this observation we concluded that individuals with a constitutional trisomy 21 may have the similar likelihood to develop a TEL/AML1+ leukemia as BCP ALL patients without this specific predisposingfactor.     

Acute nonlymphocytic leukemia after transient myeloproliferative disorder in a patient with Down syndrome

An infant with Down syndrome (DS) and RH isoimmunization developed transient myeloproliferative disorder (TMD) during the neonatal period. At 16 months she presented with acute nonlymphocytic leukemia (ANLL). Cytogenetic studies during TMD showed trisomy 21 only but new abnormalities emerged during ANLL. She is now in complete remission 5 years after diagnosis. Patients with TMD have either trisomy 21 or mosaic 21 in blood and bone marrow but in phenotypically normal children this cell line disappears with resolution of the TMD. A review of the literature indicates that there are no clinical, hematological, or cytogenetic differences between DS children with TMD who subsequently develop acute leukemia and those who do not. However, the leukemia in the former group may differ in presentation, type, and possibly survival time from other DS children who develop leukemia de novo.     

单中心MAE方案诱导治疗儿童急性髓系白血病的合并症及疗效分析

目的 回顾性分析米托蒽醌、阿糖胞苷联合依托泊苷（MAE）方案诱导治疗初诊儿童急性髓系白血病（AML）的合并症发生情况及疗效。方法 170例AML患儿采用MAE方案诱导治疗,分析诱导治疗后的合并症及缓解率。结果 170例中男女比例为1.33：1,年龄7.4（1~15）岁,诊断时WBC 29.52（0.77~351）×10⁹/L,其中M0 2例、M2 24例、M4 2例、M5 48例、M6 3例、M7 7例,AML伴有t（8;21）（q22;q22）69例,AML伴有inv（16）（p13.1q22）或t（16;16）（p13.1;q22）15例。最常见的合并症为感染,占92.9%,其中无明确感染灶的粒缺伴发热占13.9%（22/158）,有明确感染病灶（包括血流感染）的占86.1%（136/158）;其他合并症包括非感染性腹泻、出血、药物性肝炎等。治疗相关死亡10例,其中严重感染8例、多脏器功能衰竭1例、呼吸衰竭1例。156例进行了缓解率评估,完全缓解率85.3%、部分缓解率4.5%、未缓解率10.3%。结论 MAE方案治疗儿童AML的1疗程诱导缓解率较好,合并症及治疗相关死亡原因以感染为主。     

Transient leukemia in newborns with Down syndrome

Children with Down syndrome (DS) have a 10- to 20-fold increased risk of developing leukemia, particularly acute megakaryocytic leukemia. Newborns with DS or trisomy 21 mosaicism may exhibit a particularly unique form of leukemia that historically has been associated with a high rate of spontaneous remission. This transient leukemia (TL) has been shown to be a clonal proliferation of blast cells exhibiting megakaryocytic features. Its true incidence remains to be determined. At presentation, many infants are clinically well with only an incidental finding of abnormal blood counts and circulating blasts in the peripheral blood. However, in approximately 20% of cases, the disease is severe and life-threatening, manifesting as hydrops faetalis, multiple effusions, and liver or multi-organ system failure resulting in death. Of those children who enter a spontaneous remission, 13-33% have been found to develop subsequent acute megakaryoblastic leukemia, usually within the first 3 years of life, which if left untreated is fatal. This unique TL of the DS newborn has been the subject of recent clinical cooperative group trials as well as many biological and genetic research efforts. We summarize here the known clinical, biological, and cytogenetic features of TL associated with DS.     

Equal frequency of TEL/AML1 rearrangements in children with acute lymphoblastic leukemia with and without Down syndrome

Constitutional trisomy 21 is the most prominent predisposing factor to childhood leukemia, whereas the t(12;21)(p13;q22) with its molecular genetic counterpart, the TEL/AML1 fusion gene, is the most common acquired chromosomal rearrangement in childhood B-cell precursor (BCP) acute lymphoblastic leukemia (ALL). Thus, it was somewhat surprising that according to the currently available literature the incidence of TEL/AML1⁺ BCP ALL is extremely low in patients with Down syndrome (DS). To further investigate this issue in a population-based fashion, the authors retrospectively assessed the number of DS patients with a TEL/AML1⁺ ALL in two consecutive Austrian ALL multicenter trials. Accordingly, they were able to analyze 8 of 10 individuals with DS and a BCP ALL, two of whom who suffered from a TEL/AML1⁺ leukemia. Based on this observation they concluded that individuals with BCP leukemia and a constitutional trisomy 21 may have similar likelihood to have a TEL/AML1 rearrangement as BCP ALL patients without this specific predisposing factor.     

Translocation t(11;19) (q23;p13) in a child with myelomonocytic leukemia following 2 years after chemotherapy for pneumoblastoma

A child, who received successful chemotherapy for pneumoblastoma, developed a myelomonocytic leukemia with translocation t(11;19)(q23;p13) 2 years later. Although this leukemia did not present with features generally associated with therapy-related leukemias, we think this hematologic disease to be secondary to previous chemotherapy. Involvement of chromosome 11q23 is common in acute leukemia and seems to be more significantly related to ANLL in young children (M4 and M5 FAB classification). However, our observation and previous reports suggest that this chromosomal abnormality might be more frequent in therapy-related leukemias. The responsibility of etoposide and cisplatin may be discussed in such secondary malignancies. © 1993 Wiley-Liss, Inc.     

A translocation t(5;15)(q15;q11-13) infant case with acute lymphoblastic leukemia and literature review: prognosis implications

Infant acute lymphoblastic leukemia (ALL) represents poor prognosis despite intensive chemotherapy. Rearrangements of chromosome 11q23 are not observed in 34% of the cases. Infant ALL patients with t(5;15)(p15;q11-13) are rare and sporadic. In large series of infant ALL studies, 6 patients have been reported. We present a new case of an infant ALL patient with t(5;15)(p15;q11-13), and a literature review. Considering the data provided by our case and previous reports, we reinforce that this chromosomal abnormality is characteristic of ALL patients under 12 months of age sharing break point in 5p15 and 15q11-13 and strengthen the existence of an infant ALL subgroup characterized by pre-B L1 ALL, CD10-positive, complete remission (100%), and event-free survival (71%), with a relatively good prognosis and clearly less severe than the 11q23 rearrangement cases. This abnormality can be considered a recurrent abnormality on this nosologic group.