Constitutional pericentric inversion of chromosome 9 and acute leukemia

In view of the recent reports demonstrating delayed engraftment after autologous and allogeneic transplantation from donors with constitutional pericentric inversion of chromosome 9, [inv(9)], we conducted a retrospective study on six patients with acute leukemia and inv(9) to investigate if there is an impaired engraftment potential of the inv(9) hematopoietic stem cells. All but one of our patients had poor outcome. The hematopoietic recovery after induction chemotherapy was not prolonged. It is possible that the hematopoietic defects of inv(9) become more apparent after repeated courses of chemotherapy. Alternatively, the number of patients in our series may have been too small to detect a partial hematopoietic defect in patients with constitutional inv(9). Larger studies are required to confirm our findings.     

Karyotypic evolution in patients with acute myeloid leukemia

Karyotypic evolution was found in 13 of 42 (31%) patients who were examined serially; if only those patients who were examined during successive stages of active leukemia were included, karyotypic evolution was revealed in 13 of 21 (62%). A further 6 patients showed multiple cytogenetic clones when leukemia was diagnosed. We did not find nonrandom chromosome involvement in the karyotypic changes, reported by others, notably trisomy #8. Our data for all patients who showed cytogenetic clones at some stage of their disease suggested that clones occurred with a higher incidence and arose earlier in patients with myeloblastic leukemia than in patients with myelomonocytic and monocytic leukemia. Patients showing karyotypic evolution tended to have longer than average survivals and to have had an abnormal karyotype when leukemia was diagnosed. The mode of preparation of hematologic samples, whether direct or cultured, has a bearing on karyotypic findings and could influence studies of karyotypic evolution.     

Association of an inversion of chromosome 16 with abnormal marrow eosinophils in acute myelomonocytic leukemia. A unique cytogenetic-clinicopathological association

We identified 18 patients with an inversion of chromosome 16, inv(16)(p13q22), among 308 patients with newly diagnosed acute nonlymphocytic leukemia. Each of these 18 patients had acute myelomonocytic leukemia (M4 subtype) and eosinophils with distinctly abnormal morphology, cytochemical staining, and ultrastructure. These eosinophils constituted from 1 to 33 per cent of the nucleated marrow cells. In our series, every patient with acute myelomonocytic leukemia and abnormal eosinophils also had an abnormal chromosome 16. This subgroup of M4 patients had a good response to intensive therapy designed to induce remission; 13 of 17 treated patients entered a complete remission, and 10 remain in first remission. Thus, patients with an inversion of chromosome 16 appear to represent a unique cytogenetic-clinicopathological subtype of acute nonlymphocytic leukemia with a favorable prognosis.     

Trisomy of chromosome 22 in acute myelomonocytic leukemia

A patient with acute myelomonocytic leukemia type M4, with a trisomy 22 as the only chromosomal abnormality is reported. All six previously published cases with this anomaly had acute myeloid leukemia. The subtype was AMMoL in five patients, and the subtype of the sixth one was not indicated.     

Therapy-related acute nonlymphocytic leukemia with inversion of chromosome 16 and a sustained remission

Acute nonlymphocytic leukemia, apparently without a preleukemic phase, developed in a 48-year-old male who had received oral cyclophosphamide and razoxane in succession. Inversion of chromosome #16 was present in association with the morphologic features typically seen with this abnormality in de novo acute leukemia. Conventional chemotherapy resulted in complete remission, which lasted for 13 months. The importance of performing cytogenetic studies in cases of secondary leukemia is emphasized.     

Inversion of chromosome 16 with the Philadelphia chromosome in acute myelomonocytic leukemia with eosinophilia. Report of two cases.

Two cases are described with the rare combination of inv(16)(p13q22), strongly associated with acute myelomonocytic leukemia with eosinophilia, M4Eo, and the Philadelphia translocation, t(9;22)(q34;q11), hallmark of chronic myeloid leukemia (CML) and rarely found, (less than 1%), in acute nonlymphocytic leukemia. The patients were: case 1, a 9-year-old girl presenting with a white blood cell count (WBC) 42 x 10(9)/L with 32% blasts and bone marrow with blasts and eosinophil precursors consistent with M4Eo, and case 2, a 25-year-old man with WBC 34.7 x 10(9)/L with 13% blasts and bone marrow with features of M4Eo and basophilia. Both patients achieved remission but died following bone marrow transplantation in first remission (case 1) or in relapse (case 2). Cytogenetic findings were: case 1, at diagnosis, 46,XX,inv(16)(p13q22)(21)/46,XX,t(9;22) (q34;q11),inv(16)(8)/46,XX(10), and case 2, at diagnosis, 46,XY,t(9;22) (q34;q11),inv(16)(p13q22) (16) and in remission, 46,XY,t(9;22)(q34;q11) (1)/46,XY (24). Investigation of the breakpoint on 22 in case 1 with Southern blotting and the polymerase chain reaction demonstrated the presence of a p190 mRNA and a breakpoint typical of acute leukemia. Thus a diagnosis of M4Eo was supported by clinical and cytogenetic sequelae in each case; the Ph in case 1 was apparently secondary to inv(16), in case 2 the Ph probably preceded inv(16) in the etiology of the leukemia.     

A family with pericentric inversion of chromosome 12

Summary A heterozygous pericentric inversion of chromosome 12 (inv(12)) was prenatally diagnosed. The breakpoints were localized to p12.3 and q14, resulting in more than one-third of the total length of the chromosome being inverted. The inversion was transmitted from the father whose phenotype was completely normal. The newborn also showed normal phenotype and grew without any clinical problems. The parents had no history of infertility. Based on these facts, it is indicated that pericentric inv(12) (p12.3q14) does not affect phenotype.     

Familial pericentric inversion of chromosome 8

Eight children from seven presumably unrelated families were identified independently as having an unbalanced recombinant chromosome resulting in the presence of extra material on the short arm of a chromosome 8. Parental chromosomes were analyzed, and one member of each couple (four fathers and three mothers) was found to carry a pericentric inversion of a chromosome 8 [inv(8)(p23q22)]. The propositi had an unbalanced recombinant chromosome [rec(8),dup q,inv(8)(p23q22)]. The affected infants all had developmental delay, congenital heart disease, and unusual appearance. A common origin of the pericentric inversion was suggested because of geographic location and Mexican--American ancestry of the seven families.     

Biclonal chromosome evolution of chronic myelomonocytic leukemia in a child

A monosomy 7 was first detected in a 6-month-old boy with a chronic myelomonocytic leukemia. After etoposide treatment, relapse occurred after 29 months, with transformation of the disease into an acute myeloblastic leukemia. After bone marrow transplantations, two abnormal clones were found in marrow cells: 45,XY,-7,del(12)(p11p12)(66%), and 45,XY,-7,t(3;12)(q26;p12)(33%). Several karyotypic studies performed until the terminal phase exhibited the persistence of these two clones in the same proportion, although both independently acquired additional and often similar anomalies. The clone with t(3;12) acquired der(7),der(11),der(17),der(8),der(10),-5,-20, and the clone with del(12p), del(5q),der(4),der(8),der(10),der(17),-5,-20. The anomalies in 12p12 appear to represent an important although secondary event of the neoplastic process. The other anomalies may correspond to either those of a secondary acute nonlymphocytic leukemia, since they occurred after treatment by etoposide and alkylating agents, or to the natural evolution of myelomonocytic leukemia.     

A case of chronic lymphocytic leukemia with a constitutional pericentric inversion of chromosome 1

Chronic lymphocytic leukemia (CLL) has been reported to be associated with various chromosomal aberrations, the most common being trisomy 12 and structural rearrangements involving 13q, 11q, and 17p. We present a case of CLL with a constitutional pericentric inversion of chromosome 1.     

Deletion of CBFB in a patient with acute myelomonocytic leukemia (AML M4Eo) and inversion 16

Acute myelomonocytic leukemia with bone marrow eosinophilia (AML M4Eo) is a subtype of AML with distinct morphological features. Inversion (16)(p13.1q22), t(16;16)(p13.1;q22), and del(16)(q22) are nonrandom abnormalities associated with AML M4Eo and a favorable prognosis, compared with the standard risk group for AML. Deletions of the proximal region of the MYH11 gene located at 16p13.1 have been detected in about 20% of patients with inv(16), with an undetermined effect on patient survival. We present the case of a patient with AML M4Eo and inversion 16 with a distal deletion of the CBFB gene at 16q22 detected with fluorescence in situ hybridization. To our knowledge, only one previous report of a similar deletion has appeared in the literature.     

Familial Miller-Dieker syndrome associated with pericentric inversion of chromosome 17

Recently it has been shown that most cases of the Miller-Dieker syndrome (MDS) are caused by deletion 17p13.3. All familial cases have been associated with a balanced reciprocal translocation in a carrier parent and unbalanced translocations in their affected offspring. We report a new case of familial MDS in whom the mother carries a pericentric inversion of chromosome 17. She has had two children with MDS, one of whom was shown to carry a recombinant 17 consisting of dup(17q) and del(17p). The high frequency of familial MDS and its consistent association with balanced chromosomal rearrangements in one of the parents makes it important to do high-resolution chromosome analysis on all patients with MDS and possibly all patients with lissencephaly. Finding a familial balanced rearrangement makes prenatal diagnosis of this condition feasible.