An analysis of chromosome findings in non-Hodgkin's lymphomas

Unusual Interstitial Deletion of the 8q 12 Band in a Case of Acute Monocytic Leukemia

The authors describe a case of acute monocytic leukemia with a clonal deletion of the 8q12 band as a single chromosomal aberration. On the basis of this and other reports from the literature, they suggest that the 8q1 region, hitherto considered significantly involved in solid tumors, may be important also for hematologic malignancies.

Isolated isochromosome 17q: a distinct type of mixed myeloproliferative disorder/myelodysplastic syndrome with an aggressive clinical course

A clinicopathologic study was performed on 15 patients with haematological malignancies in which isochromosome 17q [i(17q)] was the sole structural chromosome abnormality identified in bone marrow. The data indicated that an isolated i(17q) is associated with a distinct type of mixed chronic myeloproliferative/myelodysplastic disorder with an aggressive clinical course. The patients ranged in age from 37 to 83 years (median 60) with a M:F ratio of 3:1. All cases were chronic myeloid disorders with mixed proliferative and dysplastic features, making classification difficult. 11 patients tested for BCR/ABL gene fusion were normal. A low bone marrow blast count (<5%) at presentation was a typical finding. All cases had severe myeloid dysplasia which included non-segmented neutrophils and an increase in the monocyte/macrophage lineage. Fluorescence in situ hybridization (FISH) analysis of one case showed the i(17q) to involve all myeloid lineages, but not the lymphocytes. For cases with complete follow-up (n = 11) the median survival was 2.5 years (range 0.83-5.25) and 64% progressed to AML prior to death. The following features were identified which defined the haematological disorder associated with an isolated i(17q): (1) adult patient, (2) chronic myeloid disorder with clonal involvement of all myeloid lineages, (3) mixed chronic myeloproliferative/myelodysplastic features, (4) severe hyposegmentation of neutrophil nuclei, (5) prominence of the monocyte/macrophage lineage, (6) high risk for progression to AML, and (7) median survival of 2.5 years.

Deletion 20q in association with Philadelphia chromosome positive acute lymphoblastic leukemia. A report of two cases

Cytogenetic deletions involving the long arm of chromosome 20 are thought to be characteristic of myeloid disorders. We report clinical and cytogenetic observations of two adult patients with Philadelphia chromosome positive acute lymphoblastic leukemia: one with a smaller 20q deletion that was the sole cytogenetic abnormality in a persisting remission clone, the other with a larger 20q deletion that was a late addition to the leukemic clone at disease relapse following allogeneic bone marrow transplantation.

Cytogenetic study of B-cell lymphoma of mucosa-associated lymphoid tissue

The recently described B-cell lymphomas arising in mucosa-associated lymphoid tissue (MALT) form a distinct clinico-pathologic group of non-Hodgkin's lymphoma, and therefore would be expected to be characterized by a recurrent chromosomal aberration. We have analyzed the cytogenetics of 23 cases of MALT lymphomas arising in the stomach, small intestine, lung, and lacrimal gland. In each case the presence of an abnormal clonal cell population was confirmed by the identification of rearranged bands when digested tumor DNA was hybridized with a probe to the joining region of the immunoglobulin heavy chain gene. Metaphase spreads were obtained in 14 cases, of which 9 cases showed an abnormal karyotype. Although no unifying aberration was detected, rearrangements of chromosome 1p, and numerical abnormalities of chromosomes 3 and 7, may play a role in the genesis of these tumors.

Chromosomal fragile site expression in dogs: I. Breed specific differences

Peripheral blood lymphocytes from clinically normal Doberman pinscher and boxer dogs were cultured for folate-sensitive and, in preliminary studies, aphidicolin-inducible fragile site expression. Both autosomal and X chromosomal fragile sites were observed in canine cells cultured under folate/thymidine depletion and in cells cultured in medium containing aphidicolin. Results from the three dogs evaluated for both folate-sensitive and aphidicolin-inducible fragile site expression showed that the frequency of fragile site expression was significantly (P less than 0.05) greater in cells cultured in medium containing aphidicolin than in cells cultured in folate/thymidine-depleted medium. Cells from the boxer dog expressed a high percentage (66.67%) of aphidicolin-inducible fragile sites in contrast to the Doberman pinscher dog in which only 21.10% of the lymphocytes expressed aphidicolin-inducible fragile sites. The frequencies of spontaneous and folate-sensitive fragile site expression did not vary significantly by breed of dog. Age of dog was significantly and positively correlated with frequency of folate-sensitive fragile site expression in dogs of the boxer breed, but not in dogs of the Doberman pinscher breed. The dog X chromosome expressed three folate-sensitive and aphidicolin-inducible fragile sites. The G-band location of these three fragile sites showed homology with three recognized constitutive common fragile sites on the human X chromosome: Xp22, Xq21, and Xq27.2. Two specific autosomal fragile sites were identified, one on the distal end of the long arm of chromosome 1 and one on the distal end of the long arm of chromosome 8. Other autosomal fragile sites were also apparent but could not be assigned reliably to specific chromosomes.

Stepwise development of chromosomal abnormalities in angioimmunoblastic lymphadenopathy

Cytogenetic studies of lymphoproliferative diseases, such as angioimmunoblastic lymphadenopathy (AILD), may provide a clue to the understanding of tumor development. Angioimmunoblastic lymphadenopathy may evolve from a nonmalignant lymphoproliferation into a peripheral T-cell lymphoma or even into a high-grade B-cell lymphoma and thus offers the chance to observe cytogenetic changes during lymphoma development. We report the cytogenetic findings in 24 cases of AILD. They are discussed together with 18 previously published cases from the same series. A striking feature was that unrelated chromosome abnormalities, both clonal and nonclonal, were frequently observed. Eighteen of 25 cases with aberrant clones show trisomy 3 (a characteristic chromosome abnormality in peripheral T-cell lymphoma), trisomy 5, or both. This finding provides cytogenetic evidence that these cases are definitely peripheral T-cell lymphomas. From the results of the 42 cases, hypotheses of stepwise evolution of the chromosome abnormalities in AILD are deduced: the first step is the appearance of chromosome abnormalities in different cells because of a genetic instability. At this time, clonal proliferation of T cells was already demonstrated by the rearrangement of T-cell receptor genes. As a second step, chromosomally aberrant clones become established. A cytogenetically detectable monoclonal proliferation represents the third step.

Abnormalities involving chromosome 6 in newly diagnosed patients with non-Hodgkin's lymphoma. Nebraska Lymphoma Study Group

Several cytogenetic abnormalities involving chromosome 6 occurring in non-Hodgkin's lymphoma (NHL) have been described. We report 34 newly diagnosed patients with NHL who had an abnormal chromosome 6 on initial biopsy. Monosomies (n = 5), trisomies (n = 6), deletions of 6q (n = 13), and isochromosomes 6p (n = 9) were frequently observed and translocations were rare. As compared with 70 other NHL patients with cytogenetic abnormalities, the patients with an abnormal chromosome 6 had a higher frequency of immunoblastic lymphoma (p less than 0.001). These patients also were more likely to have B symptoms (p = 0.02). Patients with a breakpoint at 6q11-16 all had a deletion of the distal portion and also were more likely to have B symptoms (p less than 0.001). Most patients with breakpoints at 6q21-25 had a deletion associated with a lower frequency of stage IV disease (p = 0.03) and a higher complete remission (CR) rate (p = 0.03). The patients with an i(6p) had a lower frequency of stage IV disease (p = 0.03), and the patients with a trisomy 6 had a shorter median survival (p = 0.005). Our results suggest that chromosome 6, especially the long arm, carries important information for the clinical behavior of NHL. Future studies are necessary to resolve the molecular defects.

Chromosome analysis of 30 cases of non-Hodgkin's lymphoma

Karyotype analysis is now a routine procedure in the clinical evaluation of leukaemia because of its value in diagnosis and prognosis. This is not yet so for lymphoma because the relative paucity of data available has prevented an evaluation of its usefulness. We therefore karyotyped 30 unselected cases of non-Hodgkin's lymphoma and six controls with reactive hyperplasia. All cases were karyotyped 'blind' to diagnosis; all were classified by immunohistopathology and 29 were analysed before treatment. This is one of the four largest cytogenetic studies to be reported of untreated, immunotyped patients with non-Hodgkin's lymphoma. Chromosome abnormalities were observed in 29/30 tumour samples. The only rearrangement observed more than once was the 14;18 translocation. The combined results of this study and others indicate that while there are no unique associations between histological sub-types and chromosome rearrangements in untreated non-Hodgkin's lymphoma patients, some partial specificity does exist.

Karyotypic analysis of the human monoblastic cell line U937

Karyotypes of three sublines of the human cell line U937 showed considerable variation, but all contained four consistent marker chromosomes (i.e., 3q-, 11q-, 16p+, and 17p- chromosomes). The 11q- chromosome appeared to be derived from either an interstitial deletion in bands 11q21-23 or from a translocation with an unidentified chromosome. The presence of this chromosome was of particular interest because rearrangements of chromosome #11 at band 11q23 are often associated with malignancies of the monocytic lineage. The possible significance of these findings is discussed.

Chromosomal abnormalities in indolent lymphoma

Cytogenetic studies were performed on lymph node biopsies from 60 patients with indolent (low grade) non-Hodgkin's lymphoma. Thirty-two of the 39 successfully cultured biopsies had abnormal clones. The 32 abnormal clones represented the following histologies: seven small lymphocytic lymphoma (SL), eight follicular small cleaved cell lymphoma (FSC), 14 follicular mixed, small cleaved, and large cell lymphoma (FM), and three composite lymphomas. One of the composite lymphomas had FSC/DSC (diffuse small cleaved cell) and the other two FM/DM (diffuse mixed, small cleaved and large cell). Twenty-seven of the 32 biopsies were immunologically typed, and all were B cell. The clones all exhibited more structural than numerical abnormalities, and there was no difference in the modal chromosome number of the abnormal clones found in each histology. Biopsies with no normal cells were more frequently found in the SL histology (71%) than in the two follicular lymphoma groups (54%-55%). A translocation of the 14q32 segment was the most common abnormality found in all three histologies. In the follicular lymphomas a t(14;18)(q32;q21) was seen in 52% (13 of 25) of these patients, this translocation was not observed in the SL patients. Overall 84% (21 of 25) of the follicular lymphoma patients had abnormalities of 14q32 and/or 18q21. Other specific abnormalities included anomalies of chromosome #3 in FM, an abnormal 10q in FSC and FM lymphoma, and a high incidence of +18 and chromosome #1 abnormalities in patients with t(14;18). The presence of specific chromosome abnormalities in the indolent lymphoma patients suggests a relationship between certain karyotypic features and histology.

The molecular genetics of human non-Hodgkin's lymphoma

There is increasing evidence to implicate oncogenes in the etiology of Burkitt's and non-Burkitt's non-Hodgkin's lymphoma. Some of these oncogenes have been identified because of their location at common breakpoints, some because they have been found by transfection assays to be activated, and some because they have been shown to be expressed in non-Hodgkin's lymphomas. So far there is no consistent pattern of involvement between specific oncogenes and specific subtypes of non-Hodgkin's lymphoma. This may be because more than one oncogene is necessary for transformation.

Chromosomal abnormalities in non-Hodgkin lymphoma with peripheral T-cell type: effect of HTLV-I infection

Cytogenetic studies were done in lymph node and peripheral leukemic cells from sixteen patients with non-Hodgkin lymphoma with peripheral T-cell type. Ten patients were positive for human T-cell leukemia virus I (HTLV-I) proviral DNA in tumour cells and six were negative. The former group had a higher tendency for leukemic conversion and poorer prognosis than the latter. However, no definite difference on the numerical and structural chromosomal abnormalities between these two groups was found. The most frequent chromosome abnormalities: 14p+, 14q+ and No. 6 abnormalities were detected in both groups. These results may indicate that HTLV-I does not play a specific role in chromosome abnormalities of non-Hodgkin lymphoma with peripheral T-cell type.

Prognostic implication of cytogenetic findings in 106 patients with non-Hodgkin lymphoma

The cytogenetic findings in samples from 106 patients with non-Hodgkin lymphomas (NHL), histopathologically classified according to the Kiel classification, have been correlated with survival time. Clonal chromosomal abnormalities were found in 60 patients, and only normal karyotypes in ten. The chromosome analysis of the remaining samples failed. The failures did not differ in survival compared with the cytogenetically successful cases, indicating that this group is not a prognostic entity within NHL. The cytogenetic findings were classified in six ways in order to evaluate the prognostic value of the cytogenetic pattern. Multivariate analysis demonstrated that presence of clonal chromosome abnormalities and the number of aberrations both were important prognostic factors independent of histopathology, whereas, the modal chromosome number, presence of translocations, or unidentified marker chromosomes were not. Some characteristic chromosome abnormalities were correlated with survival time: Patients with a 1p+ marker or +7 had a significantly shorter survival time than patients with normal karyotypes only (NN). Patients with +3, +12, 6q-, i(17q), and t(14;18)(q32;q21) did not differ significantly from the NN group.

Frequency of constitutional chromosome alterations in patients with hematologic neoplasias

From 1978 to 1985 cytogenetic studies were performed on 718 patients with different hematologic diseases. Nine (1.25%) had a constitutional chromosome alteration. One patient had trisomy 21, four had balanced translocations and four had sex chromosome anomalies. Although the frequency of constitutional alterations was twice that seen in the newborn population, an analysis of these data and also from the literature shows a random association between constitutional chromosome alterations and hematologic neoplasias, except for patients with Down's syndrome.

Chromosomal abnormalities in lymphogranulomatosis X (LgrX)/angioimmunoblastic lymphadenopathy (AILD)

Histologically, lymphogranulomatosis X (LgrX) is a Morbus Hodgkin-like disease which until now has been considered as an abnormal immune reaction or a prelymphoma. Chromosome analyses showed that LgrX and angioimmunoblastic lymphadenopathy AILD) are characterized by chromosomal aberrations. Chromosome analyses of 18 cases of LgrX with sequential banding techniques showed abnormalities in 13 out of 18 cases. They were monoclonal in 7 cases. The most frequent abnormalities were trisomies of chromosomes Nos 3 and 5 and duplication of the X-chromosome. The abnormal karyotypes always appeared with normal mitosis in single or clonal cells. They were found in unstimulated and in PHA-stimulated cultures from lymph node and peripheral blood. Thus, it can be concluded that at least some cases of LgrX are monoclonal cell proliferations. An attempt is made to define the role of chromosomal abnormalities in the development of malignant lymphomas.

Chromosome analysis on a cell line (CE48T/VGH) derived from a human esophageal carcinoma

The cell line CE48T/VGH was established from an epidermoid carcinoma of the middle third of the esophagus of a 58-year-old male patient. Cytogenetic analysis at passages 90-99 showed that the line was hypotetraploid, with a mean chromosome number of 73. None of the 50 karyotyped cells had a normal chromosome #1 or Y. Cells with multiple copies of some of the autosomes were observed frequently. Structural rearrangements were numerous, especially of chromosomes #1, #9, #14, X, and Y.

Chromosome abnormalities in malignant hematologic disorders

Certain chromosome abnormalities have been detected in routine cytogenetic studies of patients with hematologic disorders. This article is a cytogenetic and clinical review of 28 structural and 15 numeric chromosome abnormalities. As a group, the structural abnormalities involved 40 different chromosome breakpoints and included 13 types of translocations, 8 deletions, 3 isochromosomes, 3 inversions, and 1 duplication. The numeric abnormalities included 4 types of monosomy, 10 trisomies, and a near-haploid category. We determined the relative frequency for each of these anomalies in our practice by reviewing the results of 1,228 consecutive specimens studied between 1979 and 1984 in which a chromosomally abnormal clone was found; 61% of these specimens had one or more of the selected anomalies. The three most common translocations were 9;22 translocations (378 specimens), 8;21 translocations (15 specimens), and unbalanced abnormalities derived from 1;7 translocations (13 specimens). The two most common deletions were those involving the long arm of chromosomes 5 (101 specimens) and 20 (65 specimens). The most common isochromosome was i(17q) (33 specimens). The two most common types of monosomy were loss of a Y chromosome (118 specimens) and monosomy 7 (97 specimens). The three most common trisomies were + 8 (161 specimens), +21 (53 specimens), and +19 (31 specimens). Each of the 43 anomalies was observed in patients with different types of hematologic disorders, but in most cases one kind of neoplasm usually predominated.

Two 14q+ chromosomes in malignant lymphoma: crucial cytogenetic changes on 14q

We encountered a 36-year-old white male patient with poorly differentiated lymphocytic lymphoma, whose lymph node cells showed a clonal cytogenetic change involving chromosome #14, i.e., 47,XY, + 2,der(14),t(14;14)(14pter----14q32;14q24----14q32++ +). In addition to this change, cells with a translocation between chromosomes #2 and another #14 [t(2;14)(q21;q24)], as well as a missing chromosome #8 were found. We have reviewed the literature dealing with two or more changes affecting chromosome #14 and discussed the importance of the cytogenetic change at band 14q32 in malignant lymphoma.

Cytogenetic and immunologic phenotype findings in Hodgkin's disease

There are very few chromosome studies using banding techniques of lymph nodes in Hodgkin's disease (HD), and determinations of immunologic phenotypes are scarce. We have performed both cytogenetic and immunologic studies in 12 of 22 lymph node biopsies of different histologic types obtained from 20 HD patients (no mitotic cells were found in the remaining ten lymph nodes). A near-diploid modal number was obtained in 80% of the cases, and 20% showed a bimodal distribution. Clones were observed in 50% of HD lymph nodes, with chromosome markers in 60% of them. Markers 15q+, 5p-, and der(X) and a trisomy of chromosome #21 were observed in our cases. Seventy-one percent of the lymph nodes studied showed a predominance of T lymphocytes. Within the lymph nodes, where the karyotype was determined, 4/12 lymph nodes presented a predominance of B lymphocytes, and they were all included in the group with structural chromosome abnormalities.

Clonal chromosome abnormalities in prison-acquired lymphoproliferative syndrome

Lymph nodes from five male patients with prison-acquired lymphoproliferative syndrome (PALS), which seems to be a prodrome of acquired immune deficiency syndrome (AIDS), were examined cytogenetically. Two had clonal chromosome abnormalities, i.e., 11q- and -11, and another had multiple nonclonal chromosome changes, including t(2p-;3q+),6q-,+12,14q+. These chromosome changes are also common in malignant lymphoma and suggest that the patients with PALS may be predisposed to develop malignant lymphoma.

Cytogenetic studies of a diffuse mixed cell lymphoma of T cell origin

The chromosome finding obtained from a lymph node of a patient with T cell lymphoma is described. Two different abnormal clones were found; one of them had a t(14;18)(q32;q21), along with other structural and numerical abnormalities, including 1p+q-,1p-,2p+q+, der(11),t(11;?)(q13;?),+20,+21,22p+. The other clone contained der(13),t(13;?)(q22;?).

Histiocytic lymphoma cell lines: immunologic and cytogenetic studies

Cell lines were established from 15 patients with diffuse histiocytic lymphoma (DHL) of the intermediate grade, diffuse large cell (class G), and high-grade, large cell immunoblastic (class H) types. Immunologic studies indicated that 11 of the 15 DHL cell lines were B cell in origin, 2 were histiocytic, and 2 were null cell. Cytogenetic studies revealed 1 hypodiploid, 11 hyperdiploid, and 3 near-tetraploid cell lines. Chromosome #7 was trisomic in 3 lines, chromosomes #12 in 4 lines, and chromosome #13 in 3 lines. Chromosome #2 was monosomic in 3 lines, chromosome #8 was monosomic in 5 lines, chromosome #14 in 4 lines, and chromosome #22 in 6 cell lines. This is of special interest, as chromosomes #2, #8, #14, and #22 are clearly concerned with rearrangements in Burkitt's lymphoma and immunoglobulin expression. The most common rearrangement in the DHL cell lines involved chromosome #14 at band 14q32. However, in contrast to Burkitt's lymphoma, the pattern of translocation in DHL is between chromosome #14 and usually chromosome #11 or chromosome #18. The 14;18 translocation is not restricted to patients with low-grade follicular, small cleaved cell lymphomas, as has been reported. The 14q+ chromosome is characteristic of lymphoid malignancies in general. It is due, invariably, to a translocation with the breakpoint in band 14q32, which is the locus of the immunoglobulin heavy chain genes. We propose that in each translocation, for example, chromosomes #11 or #18, an oncogene may be transposed onto chromosome #14, and that each 14q+ translocation in DHL represents an event that transposes an oncogene from another chromosome to chromosome #14.

Rearrangements of the short arm of chromosome No. 6 in T-cell lymphomas

Cytogenetic studies on four patients with T-cell lymphomas are reported. In all four the short arm of chromosome No. 6 (6p) was abnormal. In three cases it was involved in a translocation, and in one there was a deletion of the terminal part: del(6)(p23-24). One of the translocations could be identified as a t(2:6)(q24;p24). Identification was not possible in the others. These 6p anomalies were associated with complex structural and numerical abnormalities of other chromosomes in three out of four cases. In three patients chemo- and/or radiotherapy administration preceded cytogenetic investigations.

Chromosomes and causation of human cancer and leukemia. LIV. Near-tetraploidy in acute leukemia

Near-tetraploid cell populations were observed in a case of T-cell acute lymphoblastic leukemia (T-ALL) and in one of acute myeloblastic leukemia (AML). In the ALL case, hyperdiploid chromosomal changes, characterized by an isochromosome 17q [i(17q)], as well as other changes, were seen at the onset of the disease. At the first relapse, hypertetraploid cells appeared in about 10% of the mitoses in the bone marrow (BM), and by the second and third relapses, the hypertetraploidy was present in more than 90% of the mitoses in the BM. Even though karyotypic instability was evident, all abnormal karyotypes contained one or two i(17q) at every sampling. In spite of karyotypic instability at each relapse, karyotypic evolution was observed whenever relapse occurred. A normal female karyotype was confirmed in the BM of each period. Immunologic examinations performed at each sampling revealed no recognizable changes before and after the appearance of tetraploidy. In the AML case, which was classified as FAB M2, cytogenetic examination was performed at diagnosis and relapse. In both, hypotetraploid cells were observed in over 60% of the BM cells; the modal chromosome number was 90. Banding analysis was successful at relapse, and a pseudodiploid clone characterized by t(8;21) and a hypotetraploid clone with two t(8;21) and a loss of two Y chromosomes were observed in the same BM sample. A normal male karyotype was also observed in BM cells. In both cases, giant and bizarre blasts were seen in the BM. A close correlation between near-tetraploid mitoses and giant and bizarre blast cells in BM smears of the same samples was observed. Previously published tetraploid acute leukemia cases analyzed with banding methods were accumulated and compared with our two cases.

Neoplastic kappa and lambda cells in a B-PLL with chromosome translocations of both light chain gene regions

We describe a chromosome translocation t(2;13) (p11-12;p11) involving the kappa (kappa) light chain gene region (2p11-12), and a subsequent translocation t(11;22) (q23;11) involving the lambda (lambda) light chain gene region (22q11) within the same clone, in a patient with B-cell prolymphocytic leukaemia (B-PLL), of whose peripheral mononuclear cells 82% expressed (kappa) chains and 8% expressed (lambda) chains. Electron microscope (EM) studies using the immunogold method showed that both kappa- and lambda-producing cells were prolymphocytes. Immunoglobulin (Ig) gene analysis by Southern blotting demonstrated rearrangement of both Ig heavy (H) chain genes and one kappa gene. Although a lambda gene rearrangement corresponding to the minor lambda-positive population was not detected, a small monoclonal (M) band of IgM-lambda was present in the serum. The chromosome translocations and the pattern of light chain expression, particularly the lambda-producing cells, are discussed in the light of the restricted light chain expression observed in Burkitt's lymphomas with variant translocations involving the light chain genes.

Biclonal trisomy 3 in a case of epithelioid cellular lymphogranulomatosis (Lennert's lymphoma)

Biclonal trisomy 3 in a case of epithelioid cellular lymphogranulomatosis (Lennert's lymphoma) was demonstrated by Q-banding polymorphisms of chromosome #3. Seventeen of 19 mitoses with trisomy 3 showed duplication of 1 of the homologous chromosomes and the remaining 2 showed duplication of the other chromosome. It is assumed that both chromosomes #3 independently underwent nondisjunction and that this led to the development of the two abnormal clones. Moreover, there appeared to be a qualitative difference between the two clones, because one of them made up a major proportion and the other a minor proportion of the cells in both of the two samples studied at different times.

Erythrophagocytic acute lymphocytic leukemia with B-cell markers and with a 20q- chromosome abnormality

An erythrophagocytic neoplastic infiltration of the bone marrow which resembled malignant histiocytosis was found in an elderly man who, when initially examined, had fever and cytopenias. Results of cytochemical and immunologic studies were consistent with an acute lymphocytic leukemia in which the lymphoblasts showed the simultaneous expression of lymphoid stem cell and B-cell markers. Chromosome analysis revealed an abnormal clone with a deletion of part of the long arm of chromosome 20. This case illustrates (1) the occurrence of striking erythrophagocytosis by lymphoblasts at the time of initial presentation of a patient with acute lymphocytic leukemia, (2) the fact that abnormalities of chromosome 20 can occur in patients with acute lymphocytic leukemia, and (3) the capability of lymphoid malignant lesions to show the simultaneous expression of antigens that are characteristic of different stages of lymphoid differentiation.

Translocation 1;19--a new cytogenetic abnormality in acute lymphocytic leukemia

A study of the chromosomes of 125 consecutive patients with acute lymphocytic leukemia (ALL) showed the same translocation between chromosomes #1 and #19 in 5 patients. In 4 of the 5, the t(1;19)(q21;q13) was present at diagnosis. The fifth patient, who had Philadelphia chromosome positive (Ph1+) ALL, developed t(1;19) in first relapse. Trisomy 1q was involved in 2 of the 5 patients; 3 patients had additional abnormalities. All patients had low white cell counts at presentation (less than 35 X 10(9)/L), and the 4 patients tested had common ALL antigen (CALLA) positive leukemic blast cells. All achieved complete remission, including the Ph1+ ALL patient in first relapse, and survival times ranged from 4 to 21+ mo from the time the t(1;19) first appeared. Our data suggest that t(1;19) is a previously unrecognized nonrandom structural abnormality in ALL that is also found in other lymphoid malignancies. Unlike the other specific translocations, it is not associated with a poor prognosis.

Hematologic manifestations associated with deletions of the long arm of chromosome 20

We investigated 20 patients with hematologic disorders who had a clone of cells with a deletion of most of a chromosome #20 long arm (20q-) in the bone marrow. Three patients had polycythemia vera (PV), 6 had acute nonlymphocytic leukemia (ANLL), 8 had preleukemia (PL), and 3 had other myeloproliferative disorders. In our laboratory, a 20q- chromosome is found in 6% of patients with PV, 3% of patients with ANLL, and 1% of patients with PL. Among the 6 patients with ANLL and a 20q- abnormality, 3 had erythroleukemia. There were no apparent clinical differences among our patients with 20q- chromosomes compared with other patients with similar disorders who did not have a 20q- chromosome. The breakpoint of the 20q- anomaly, in each instance, was in band 20q11, but it occurred near the centromere at 20q1101 in 16 patients and at the distal part of this band at 20q1109 in 4 patients. Three of the 4 patients with a breakpoint at 20q1109 had PL.

The biology of tumor growth in the non-Hodgkin's lymphomas. A dual parameter flow cytometry study of 220 cases

Dual parameter flow cytometry studies (cell DNA content and electronic cell volume) were performed in 220 cases of non-Hodgkin's lymphoma. All cases were characterized as B or T cell malignancies, based on immunologic surface marker characteristics. Aneuploidy by flow cytometry was more common among the B cell lymphomas than among the T cell lymphomas, and was most common among the large B cell lymphomas and B cell lymphomas of intermediate size. Ploidy index distributions showed a prominent hyperdiploid peak, as well as tumor cell populations with near-tetraploid DNA contents. In serial studies, a decrease in ploidy index was observed in association with clinical and histologic transformation in one case. The highest S fractions were observed among the large and intermediate B cell lymphomas and among the aggressive T cell lymphomas. In clinical samples consisting of mixtures of diploid and aneuploid populations, the data on the aneuploid components could often be separated from other components of the mixture in multiparameter studies on the basis of the larger electronic cell volumes of the aneuploid cells. In each case, the aneuploid large cell component almost invariably had a higher S fraction than the residual component(s) of the mixture. Overall, the data are consistent with a model of clonal selection and clonal evolution in the lymphomas in which early cytogenetic abnormalities that involve little or no change in total cell DNA content are followed by cell tetraploidization that is associated with cytogenetic instability and chromosome loss over the course of time.

Indirect stimulation of B-cell proliferation in vitro by T cells, as evidenced by cytogenetic analysis of PHA-stimulated cell cultures of B-cell lymphomas

In a retrospective study of non-Hodgkin's lymphomas, the 14q+ marker was found in at least one of the samples examined from 17 patients with B-cell lymphoproliferative diseases (LPD). In the PHA-stimulated cultures, the marker was found in each sample in 10%-100% of the cells. An indirect stimulation, as indicated by a 3H-thymidine incorporation and IG secretion, of normal B cells by a T-cell mitogen, such as PHA, has been recently documented. This phenomenon is confirmed by our chromosome analysis, which demonstrated characteristic chromosome changes in PHA-stimulated cultures of patients with B-cell malignancies and indicated that the phenomenon can be observed not only in normal B cells but also in malignant B cells.

Prognostic implications of karyotype and morphology in patients with non-Hodgkin's lymphoma

Clonal chromosome abnormalities were observed in 30 patients with non-Hodgkin's lymphoma; the type of lymphoma was characterized on the basis of the International Working Formulation. The 30 patients were classified into five groups according to the chromosome abnormality. There were 8 patients with t(14;18), 3 with t(8;14), 7 with a translocation to the long arm of chromosome 3 (a 3q+ chromosome), 5 with near-tetraploidy, and 7 with other abnormalities. Among the 8 patients with t(14;18), 5 had follicular small cleaved-cell lymphoma (FSC), I had follicular mixed cell lymphoma (FM), and 2 had diffuse large-cell lymphoma (DL); the diagnosis in these 2 patients was based on extranodal tissue. All 3 patients with t(8;14) had DL and B-cell markers. Except for 1 patient, all those with a 3q+ chromosome had DL; 4 of those who were tested had B-cell or pre-B-cell markers. Four of the 5 patients with near-tetraploidy had follicular mixed-cell lymphoma, and 2 of the 7 patients with other abnormalities had T-cell lymphoma. Thus, patients with a t(8;14), a 14q+ chromosome, or a 3q+ chromosome all tend to have diffuse large-cell lymphoma, usually of the non-cleaved type. On the other hand, our data suggest that patients with FSC generally have a t(14;18) whereas those with follicular and diffuse mixed small cleaved cells and large noncleaved cells have a different pattern with modal chromosome numbers in the tetraploid range. We added 17 previously reported patients to the 30 presented here and correlated the karyotype with survival. The 6 patients with near-tetraploidy had the longest median survival, 69 months, the 15 patients with t(14;18) had the next longest, 48 months. The 4 patients with t(8;14) had the shortest survival, 12 months, and the 9 with other abnormalities had the next shortest, 17 months. Intermediate survivals of 27 and 30 months were observed in patients with a 14q+ or a 3q+ chromosome, respectively. The median survival of these various categories differs and our data, thus, indicate that the karyotypic pattern of the malignant cell may be a significant independent prognostic feature influencing the survival of patients with non-Hodgkin's lymphoma.

Karyotype evolution in B-cell lymphoid malignancy with an 8;14 translocation

To evaluate the significance of karyotypic evolution of tumor cells with an 8;14 translocation [t(8;14)(q24;q32)], we examined the clinicopathologic features and immunologic phenotypes of nine Japanese patients with various types of B-cell malignancy with the translocation. All these patients had structural rearrangements of the long arm of chromosome No. I (Iq) in a stem line or the subline of tumor cells with a t(8;14). The rearrangements were composed of a translocation involving Iq with other chromosomes and a tandem duplication of Iq, and they were exclusively associated with a partial trisomy for Iq. Two patients with diffuse large-cell lymphoma, whose tumor cells did not express surface immunoglobulins (s-Ig), had the Iq translocation in their highly complex karyotypes. Tumor cells from the other seven patients expressed s-Ig and the karyotypes were relatively simple. Among these patients, the Iq translocation was found in two patients with Burkitt's lymphoma, and the Iq duplication were observed in a stem line or the sublines from four patients with Burkitt's lymphoma-leukemia and one each with small non-cleaved-cell or diffuse large-cell lymphoma. Except for one patient in the stage of IE, these patients had a poor prognosis because of the clinical conversion of extranodal metastases in the earlier disease phase. These findings are compatible with those of Western patients with a t(8;14). Therefore, tumor cells marked primarily with a t(8;14) could have "major routes" in the karyotypic evolution, for which potentials should be recognized as clinical risk factors, and the morphologic presentation and the expression of surface immunoglobulins may be associated with the process of karyotypic evolution.

Translocations involving chromosomes #3 and #12: hematologic diseases associated with abnormalities of these chromosomes

Two hematologic cases with translocations involving chromosomes #3 and #12 are described. The first case is that of a myeloproliferative disorder (preleukemia?) associated with a (3;12)(q29;q24) translocation in the bone marrow cells. No evidence of leukemic transformation has appeared to date. The second case is that of acute leukemia (AL) (M4 type) in which leukemic cells with t(3;12)(p14;q24) were seen. The roles of chromosomes #3 and #12 in hematopoiesis are considered, and the abnormalities affecting these chromosomes in various hematologic disorders have been tabulated and correlated. Abnormalities in chromosomes #3 and #12 appear to be common and nonrandom in hematologic diseases of a premalignant and a malignant type.