Atypical chronic myelogenous leukemia with Philadelphia (Ph') chromosome and an additional translocation

Karyotype evolution in CML: high frequency of translocations other than the Ph

The karyotypes of 33 Philadelphia-positive chronic myelogenous leukemia patients during the blastic phase are reported. Only three patients (9%) had a Philadelphia clone without further chromosomal aberrations, whereas, all the others had karyotype evolution. Aside from some nonrandom abnormalities (+8, i(17q), +Ph, +19) we found a higher frequency of clones with random structural rearrangements (13 cases, 39.4%) than previously reported. From a clinical point of view, however, the additional chromosomal (structural) abnormalities do not significantly influence the patients' survival.

Translocation (1;17) in accelerating and blast phases of chronic myelogenous leukemia

A translocation (1;17)(p11;q11) has been observed in two chronic myelogenous leukemia (CML) patients studied during the accelerated or acute stages of their diseases. In a review of the literature, four additional cases of t(1;17)(p11;q11) were identified, suggesting that this marker may be specific for the terminal phase of CML.

Translocation t(1;20)(q21;q13) in an azoospermic man

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"Masked" Ph1 chromosome in a complex three-way translocation

A patient with myelofibrosis was found to have a 46,XX,del(1)(q24),del(11)(p11),-22,+mar karyotype in unstimulated peripheral blood (PB) and spleen cells. On detailed cytogenetic examination it was determined that this patient had an apparently "masked" Ph1 chromosome contained in a complex three-way translocation. Since phytohemagglutinin (PHA)-stimulated PB and spleen cells were essentially normal, the masked Ph1 chromosome was assumed to be an acquired cytogenetic abnormality. The portion missing from the masked Ph1 chromosome was apparently translocated onto del(1). Thus, the detailed karyotype was 46,XX,t(1;11;22)(q24;p11;q11 or q12),t(1;22)(q24;q11 or q12). This complex rearrangement was present primarily in cells belonging to the granulocyte-macrophage cell lineage, whereas E-rosetting cells, and presumably T lymphocytes, had normal karyotypes.

Break points in chromosome #1 abnormalities of 218 human neoplasms

A survey of 343 break points that lead to chromosome #1 abnormalities in 218 human neoplasms showed that 49.9% were located in or immediately adjacent to the centromeric heterochromatin. Amongst rearrangements with breaks in bands p 12-q21 were 27 isochromosomes, 22 translocations of the long arm, and four translocations of the short arm to the heterochromatic regions of other chromosomes, and 35 deletions resulting in chromosomes consisting mainly or solely of one arm. Deletions following breakage at various sites in the short arm of chromosome #1 are frequent in malignancies and are quite often found in cells that are trisomic for the long arm. It is suggested that fragility of chromosomes generated as a result of early events in carcinogenesis may be one source of chromosome rearrangements, including those of chromosome #1, on which selection can operate and give rise to progressively more malignant clones.

Karyotype evolution in a case of chronic myelogenous leukemia with an unusual Philadelphia chromosome translocation, t(4;22), and an additional translocation, t(3;5)

A patient with chronic myelogenous leukemia was found, at the time of diagnosis, to have an unusual Philadelphia chromosome translocation, t(4;22) (q35;q11) and an additional previously unreported translocation, t(3;5) (q27;q22). The blastic crisis, which occurred after 14 months, was characterized by the appearance of i(17q). Ten months later, two different hyperdiploid cell lines with 50 chromosomes were found in about 20% of the metaphases examined.

Chromosomes and causation of human cancer and leukemia: XL. The Ph1 and other translocations in CML

To date, 85 cases with unusual Ph1 translocations have been described and are summarized in the present work. Of the 85 translocations, 41 were simple and 44 complex. Only chromosomes #1, #4, #8, and #20 and the Y have not been found to be involved in simple translocations and #12, #16, #18, #20 and the Y in complex ones. Chromosomes #18, #20, and Y have not been involved to date in either complex or simple Ph1 translocations. Four cases have been reported in whom more tan three chromosomes were involved in the Ph1 translocation and only four cases in whom the #9 was not involved in complex Ph1 translocations. The chromosomal changes, in addition to the Ph1, accompanying unusual Ph1 translocations in CML are not different from those seen in cases with the standard type of Ph1 translocation. Translocations (other than the Ph1) in CML occur in less than 1% of the cases and, to date, have found to involve all the chromosomes except the X and Y. With rare exceptions, in complex Ph1 translocations 1) the distal end of #22 is translocated to a third chromosome (i.e., other than #9), a part of which is translocated to #9, #2) the breaks in the involved chromosomes probably occur concomitantly, and 3) a characteristic PH1 chromosome is present. The survival of patients with CML and unusual or complex Ph1 translocations does not differ significantly from that of patients with the standard Ph1-translocation.

Chromosome 1 in 26 carcinomas of the cervix uteri: structural and numerical changes

Cytogenetic studies on 26 carcinomas of the cervix showed that chromosome 1 was consistently involved in the changes: either one or more structurally abnormal chromosomes or a relative excess of normal chromosomes were present. Several types of structural change were repeatedly seen: short arm deletions (1p-, in seven tumors); long arm isochromosomes (i(1q), in six tumors); and translocations of unidentified chromosomal material onto one of the arms (possibly in eleven tumors; in four of these, there was an additional C-band on the long arm). In one tumor, there was a short arm isochromosome (i(1p)). The most consistent feature of the aneuploid complements of these tumors appeared to be the presence in excess of the centromeric region and at least part of the adjacent heterochromatin of chromosome 1.

Chromosome changes in a patient achieving complete remission in the acute phase of chronic myelogenous leukemia

A patient with chronic myelogenous leukemia (CML) had a Philadelphia chromosome (Ph') [t(9q+;22q-)] in all cells and trisomy C in 13% of cells (later determined to be trisomy 8) at the time of diagnosis. After 21 months of intermittent treatment with busulfan, the acute phase developed with the appearance of an additional abnormality (trisomy ? 19). During a complete remission and reconversion to the chronic phase, trisomies 8 and ? 19 DISAPPEARed, although the Ph' remained. Following a period of marked thrombocytosis, a second relapse occurred with the reappearance of both marker chromosomes.