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Chromosome translocations are among the most common genetic abnormalities in human leukemia. Each translocation may affect a different pair of genes. The abnormally expressed genes that result from the different translocations provide a rich source for identifying specific markers for clinical diagnosis of each translocation. Microarrays have identified genes differentially expressed in different translocations but the results between laboratories are not always compatible. We used SAGE to quantitate gene expression in bone marrow (BM) samples from 22 patients with four types of AML, namely de novo AML M2 with t(8;21), AML M3 or M3V with t(15;17), AML M4Eo with inv(16), AML M5 with t(9;11) or secondary t(9;11).We generated SAGE libraries from CD15+ leukemic myeloid progenitor cells, collecting over 106 SAGE tags, of which 209,486 were unique tags; 136,010 were known genes and ESTs, and 73,476 were novel transcripts. SAGE tags for further analysis were selected based on a 5-fold difference between patients’ samples and normal CD15+ BM; they were also statistically significantly different at the 5 % level. Using these strict criteria, we identified 1,571 unique tags, of which 1,405 were known genes and ESTs, and 166 were novel transcripts that were either specific for each translocation or were common for all four translocations. Changes in expression of these known genes which fall into different gene ontogeny functional categories varied by translocation. For example, those associated with macromolecular biosynthesis, transport and transcription were most altered in the t(8;21); those related to defense response and apoptosis were altered in the t(15;17); cell proliferation genes were most affected by the t(9;11). Cell surface receptor signaling, intracellular signaling and RNA processing were altered in treatment related but not in de novo t(9;11). From this analysis, we identified the functional molecular signature of each translocation. We designed a custom microarray to validate our SAGE data analysis. Our initial pilot microarray experiment with 96 genes that were specific for each translocation or common for all translocations used mononuclear cells from normal and patient BM and translocation cell lines, ME-1, THP-1, Mono Mac-6, Kasumi 1, NB-4; the array data from BM matched the SAGE data for 48-75 % of genes and the majority of cell lines, except ME-1, matched at least 70 % with the SAGE results for the appropriate translocation. We have now designed a full-scale microarray that contains over 400 probes including 250 known genes, 61 ESTs, 45 novel sequences and 48 genes reported by others. We will test at least 100 patients’ samples with the four translocations to validate which genes provide a robust, reproducible “fingerprint” for each translocation and for all translocations. We will correlate our microarray data with age, sex, race, response to treatment, survival and other mutations (FLT3, MLL ITD, etc) to identify any transcripts that might reliably define these categories. Our results will provide new insights into genes that collaborate with each translocation to lead to a fully leukemic phenotype.

The t(8;21)(q22;q22) that results in an AML1-ETO fusion gene is frequently detected in de novo and in therapy-related acute myeloid leukemia (AML) patients. Most t-AML patients with t(8;21) have received treatment with topoisomerase (topo) II inhibitors for primary tumors. In our previous study in 31 de novo leukemia patients with t(8;21) genomic breakpoints clustered in each three breakpoint cluster regions (BCRs) in intron 5 in AML1 and in intron 1b in ETO which tended to colocalize with DNA topo II cleavage and DNase I hypersensitive sites, implicating these chromatin structural elements in the mechanisms leading to the t(8;21). In this study, we cloned genomic breakpoints in AML1 and ETO in both derivative chromosomes in six t-AML leukemia patients with t(8;21), all of whom were treated with topo II inhibitors for previous tumors. Genomic breakpoints in AML1 and ETO in t-AML patients cluster in the same BCRs previously identified in de novo patients with t(8;21). Our results are unexpected because in MLL translocations involving 11q23, the location of breakpoints in MLL in de novo and in t-AML patients is different. There were deletions and duplications at the breakpoints in both AML1 and ETO, and microhomologies or non-templated nucleotides occurred at most of the genomic fusion junctions. No specific recombination motifs were identified at or near the breakpoint junctions. Both deletions and duplications were larger in de novo leukemia patients than in t-AML patients. In each 10 de novo patients, the deletions ranged from 5 to 556 bp (251 bp in average) in AML1 and from 6 to 225 bp (88 bp) in ETO, whereas in t-AML patients the deletions in AML1 ranged from 1-111bp (39 bp) in three and from 2-125 bp (32 bp) in ETO in five patients. Duplications in AML1 in seven de novo patients ranged from 1-141 bp (76 bp) and in ETO in eight patients from 51 to 355 bp (185 bp); in contrast, duplications in AML1 were 1, 2 and 1085 bp in three t-AML patients, and only one t-AML patient had a duplication (1 bp) in ETO. Similarly, only very small (2-7 bp) deletions or duplications were detected in MLL and CBP in t-AML patients with t(11;16). Thus, there are some unexplained differences in non-homologous end joining repair in de novo and therapy-related leukemia. We mapped a scaffold attachment region (SAR) in intron 4 of AML1, and two SARs in intron 1b of ETO that are near the BCRs. Moreover, we analyzed the free energy (delta G) that is needed to unwind double strand DNA of the BCR-bearing introns in AML1 and ETO and found that the topo II cleavage sites we identified in both genes have the lowest delta G value suggesting that topo II cleaves DNA at the point of the lowest free energy. Our study suggests that illegitimate recombination between AML1 and ETO in the t(8;21) in both de novo and therapy-related leukemia patients is similar, and that topo II cleavage sites with the lowest free energy provide vulnerable sites for breakage. Non-homologous end joining repair is a likely mechanism involved in the formation of the t(8;21).

The U937 cell line was studied with the fluorescence in situ hybridization (FISH) technique using phage and cosmid probes which were mapped and ordered on IIq. Although this cell line was thought to have a del(IIq), FISH demonstrated that IIq was translocated to lop and that the breakpoint on IIq is centromeric to the MLL gene. This I0; II translocation appears to be a t(I0;II)(p I3-I4;q I4–2I), which was recently reported to be a recurring translocation in malignant hematologic disease. This cell line will be a good tool for the study of this chromosomal rearrangement.

THIS ARTICLE presents a summary of the results of investigations to detect the various genetic changes that have been identified in malignant cells, concentrating on those malignant diseases that have been well characterized genetically. Various techniques are reviewed elsewhere.1The correlation of the genetic changes with features that aid in the distinction of different tumors or that have prognostic significance will be emphasized. The explosive growth in this area of clinical investigation causes any review of this sort to become out of date rapidly. Nonetheless, these examples are important illustrations of the future of medical practice. Detailed summaries of chromosome abnormalities in cancer have been described previously.2,3The article is divided into two major parts, hematologic malignant diseases and solid tumors. At present, we know much more about the hematologic disorders, especially leukemia and lymphoma.4This is rapidly changing as many laboratories are actively investigating the genetic

The past decade has witnessed significant advances in our understanding of some aspects of cancer biology, especially the genetic changes in cancer cells. During this period, the critical role of chromosome changes in the complex process of malignant transformation has received further recognition. For years, the cytogenetic database has been tapped by molecular biologists who have used the information as a starting point to tackle problems at the molecular level. Cytogenetic analysis was the key to defining two major categories of genetic rearrangements, namely, recurring chromosomal translocations and consistent deletions. These abnormalities have now been shown to contribute to the oncogenic process through either the modification and activation of cellular protooncogenes or the inactivation of tumor suppressor genes. Clinicians have also used cytogenetic information to assign prognosis in acute leukemia, lymphoma, and certain solid tumors. Thus, the karyotypic picture of any particular tumor has become of value to clinicians, biologists

The Philadelphia chromosome (Ph1) of chronic myelogenous leukemia (CML) contains sequences from chromosome 9, including the ABL protooncogene, that have been translocated to the breakpoint cluster region (bcr) of chromosome 22, giving rise to a bcr-ABL fusion gene, whose product has been implicated in the genesis of CML. Although chromosome 22 translocation breakpoints in CML virtually always occur within the 5.8- kilobase (kb) bcr, chromosome 9 breakpoints have been identified within the known limits of ABL in only a few instances. For a better understanding of the variability of the breakpoints on chromosome 9, we studied the CML cell line BV173. Using pulsed-field gel electrophoresis (PFGE), large-scale maps of the t(9;22) junctions were constructed. The chromosome 9 breakpoint was shown to have occurred within an ABL intron, 160 kb upstream of the v-abl homologous sequences, but still 35 kb downstream of the 5′-most ABL exon. bcr-ABL and ABL-bcr fusion genes were demonstrated on the Ph1 and the 9q+ chromosomes, respectively; both of these genes are expressed. These results suggest that the 9;22 translocation breakpoints in CML consistently occur within the limits of the large ABL gene. RNA splicing, sometimes of very large regions, appears to compensate for the variability in breakpoint location. These studies show that PFGE is a powerful new tool for the analysis of chromosomal translocations in human malignancies.

The aggressive clinical course and the distinctive histologic, cytochemical, and cytogenetic features of an adult non-Sezary T-cell lymphoma with suppressor activity have been investigated. Morphological and ultrastructural analysis of neoplastic cells from peripheral blood and involved lymph nodes revealed cells with convoluted nuclei, prominent cytoplasmic azurophilic granules, well developed Golgi apparatus, short strands of endoplasmic reticulum, and moderate numbers of ribosomes and mitochondria. Cytochemical reactions showed acid phosphatase (ACP) positivity in virtually all of the neoplastic cells; and a substantial percentage of the cells, the tartrate-resistant acid phosphatase (T-ACP) isoenzyme was observed. Granular naphthyl acetate esterase (A-EST) reactivity was not present. The histological and cytochemical features of these neoplastic suppressor cells were compared with those recently described for the suppressor T-cell fraction isolated from normal peripheral blood T-cell by Fc gamma- rosette formation. The aneuploid clone had 47 chromosomes with multiple complex abnormalities, including a 14q + chromosome formed by the tandem translocation of two no. 14 chromosomes and translocations involving the long arms of no. 2 and no. 9 at band 9q34. These latter changes are particularly common in T-cell disorders. The extensive analysis of this histologic, cytochemical, and cytogenetic features of this adult T-cell suppressor lymphoma should help to clarify the criteria for distinguishing among the subsets of T-cell neoplasms with definable immunologic function.

Clinical and cytogenetic studied were done on 12 patients with lymphoblastic lymphoma. The ages of the patients ranged from 17 to 58 years (median, 24.5 years). Males predominated by a ration of 5:1. Ten of the 12 patients had a mediastinal mass at diagnosis; two thirds of the patients had involvement of the bone marrow (3 of 12 patients initially were in a leukemic phase), and 5 of 12 patients had involvement of the central nervous system (CNS) with lymphoma. In all patients, the malignant cells were characterized by nuclear convolutions. Cytogenetic studies done on four patients showed clonal chromosome abnormalities in two cases. Six of the 12 patients were treated with the combination chemotherapy regimen COPA and received CNS prophylaxis; their survival was slightly longer than that of the other patients, who were treated with a variety of treatment regimens. Two of the 12 patients achieved a complete remission. The median survival of all patients was 11.5 months but was shorter in patients with initial CNS involvement or leukemia. The poor results achieved thus far in the treatment of this disease demand a new therapeutic approach.

Both cytogenetic abnormalities and in vitro growth patterns of leukemic cells have prognostic significance in acute nonlymphocytic leukemia (ANLL). The present study was undertaken to analyze the interrelationship between these two factors and response to therapy. Blast cells from 43 patients with de novo ANLL, four patients with secondary ANLL, and two patients with ANLL following a preleukemic phase were studied using both in vitro culture in methylcellulose and quinacrine chromosome banding techniques. In 19 patients with de novo ANLL, minimal growth in culture (less than or equal to 5 colonies without prominence of small clusters) was noted (Pattern I). Blast cells from the remaining 24 patients formed numerous abnormal clusters and colonies in a continuum distribution (Pattern II). Sixty-three percent of Pattern I patients had completely normal karyotypes (NN). Only 29% of Pattern II patients were NN. No Pattern I patient had only abnormal karyotypes (AA), while 25% of Pattern II patients were AA (p less than 0.05). All six patients with secondary leukemia or leukemia following a preleukemic phase demonstrated both Pattern II growth and cytogenetic abnormalities. Fifty-six percent of Pattern I patients with de novo ANLL responded to chemotherapy, 35% of Pattern II patients responded, and 0% of patients with secondary or post-preleukemic ANLL responded. The correlation between the presence of cytogenetic abnormalities in leukemic cells and a pattern of excessive, abnormal growth in vitro coupled with the trend toward poor prognosis in these patients suggests that cytogenetically abnormal cells may have a proliferative advantage both in vitro and in vivo.

Chromosome abnormalities of a clonal nature have been found in approximately 50 per cent of the patients with acute nonlymphocytic leukemia and acute lymphocytic leukemia. Patients with acute myeloblastic leukemia (M1 and M2) with only abnormal metaphases have the worst prognosis among patients with acute nonlymphocytic leukemia, whereas patients with acute myeloblastic leukemia (M1 and M2) with only normal metaphases have the best prognosis. Specific abnormalities include a t(8;21) in approximately 8 per cent of the patients with acute nonlymphocytic leukemia and a t(15;17) in approximately 50 per cent of the patients with either hypergranular (M3) or microgranular (M3 variant) promyelocytic leukemia. In patients who develop acute leukemia after cytotoxic or radiation therapy for a previous malignant disease, clonal chromosome abnormalities are almost always present.

Approximately 50% of acute nonlymphocytic leukemia (ANLL) patients studied with banding techniques have detectable clonal karyotypic abnormalities. Although there is considerable variability, certain nonrandom abnormalities are observed, including trisomy 8, monosomy 7, and the 8;21 translocation (frequently accompanied by loss of an X or Y). The 15; 17 translocation is highly specific for acute promyelocytic leukemia. Clonal evolution of the karyotype can be observed in a significant number of ANLL patients for whom serial cytogenetic analyses are obtained. Gain of a No. 8 is the most frequently observed evolutionary change. Bone marrow cells from patients who develop ANLL following treatment of a previous malignancy often have hypodiploid modal numbers and frequently show loss of all or part of a chromosome No. 5 or No. 7.

The gene IL-3 encodes interleukin 3, a hematopoietic colony-stimulating factor (CSF) that is capable of supporting the proliferation of a broad range of hematopoietic cell types. By using somatic cell hybrids and in situ chromosomal hybridization, we localized this gene to human chromosome 5 at bands q23-31, a chromosomal region that is frequently deleted [del(5q)] in patients with myeloid disorders. By in situ hybridization, IL-3 was found to be deleted in the 5q-chromosome of one patient with refractory anemia who had a del(5)(q15q33.3), of three patients with refractory anemia (two patients) or acute nonlymphocytic leukemia (ANLL) de novo who had a similar distal breakpoint [del(5)(q13q33.3)], and of a fifth patient, with therapy-related ANLL, who had a similar distal breakpoint in band q33 [del(5)(q14q33.3)]. Southern blot analysis of somatic cell hybrids retaining the normal or the deleted chromosome 5 from two patients with the refractory anemia 5q- syndrome indicated that IL-3 sequences were absent form the hybrids retaining the deleted chromosome 5 but not from hybrids that had a cytologically normal chromosome 5. Thus, a small segment of chromosome 5 contains IL-3, GM-CSF (the gene encoding granulocyte-macrophage-CSF), CSF-1 (the gene encoding macrophage-CSF), and FMS (the human c-fms protooncogene, which encodes the CSF-1 receptor). Our findings and earlier results indicating that GM-CSF, CSF-1, and FMS were deleted in the 5q-chromosome, suggest that loss of IL-3 or of other CSF genes may play an important role in the pathogenesis of hematologic disorders associated with a del(5q).

A small fraction of those individuals exposed to cytotoxic chemotherapy or radiation for the treatment of a primary malignant disease will develop a second malignancy some time later. Although exposure to the cytotoxic agents is believed to be the causative factor, the reason only certain individuals develop the second malignancy is unknown. Some studies have suggested that these individuals might be predisposed to cancer because of an inherent sensitivity to the alkylating agents used in cancer therapy. We have reported that these individuals with therapy-related acute nonlymphocytic leukemia (t-ANLL) have reduced endogenous levels of the repair protein O6-alkylguanine alkyltransferase (AGT). To further investigate the etiology of this disease, alkylation-induced sister-chromatid exchange (SCE) formation in individuals who developed second malignancies, was compared to other patient groups and normal controls. Peripheral blood lymphocytes from patients with (1) t-ANLL, (2) primary forms of acute nonlymphocytic leukemia (ANLL de novo), (3) patients with primary malignancies at risk of developing secondary disease, and (4) unexposed, healthy controls were treated in vitro with N-methyl-N'-nitro-nitrosoguanidine or mitomycin C. Baseline and mutagen-induced frequencies of SCEs were determined. These studies failed to detect any increased sensitivity in those patients who developed second malignancies as compared to controls or patients with de novo forms of the same disease. Also, no correlation between sensitivity to the alkylating agent N-methyl-N'-nitro-nitrosoguanidine and endogenous levels of the AGT repair protein was found. These results suggest that t-ANLL patients are not sensitive to SCE induction by either MNNG or MMC.(ABSTRACT TRUNCATED AT 250 WORDS)

The 14;18 translocation [t(14;18)] is the most common chromosome abnormality noted in the non-Hodgkin's lymphomas (NHL). Although the translocation is seen in various histologic subtypes, it is most commonly associated with the follicular lymphomas, especially the small-cleaved cell (FSC) and mixed-cell (FM) subtypes. The translocation breakpoint has been cloned and DNA probes from the junction on chromosome 18 can now be used to detect the genetic consequences of the translocation in tumors with few dividing cells. This will allow a more precise classification of this subset of lymphomas and should lead to better understanding of the biology of this category of lymphomas. Finally, these insights will help in the development of more effective and possibly less toxic therapy.

Three patients with acute leukemia, disseminated intravascular coagulation, and a specific acquired chromosome abnormality [t (15;17)] were found by transmission electron microscopy to have the typical distribution of granules seen in promyelocytes. However, the average granule sizes were 120, 170, and 180 nm, respectively, for the three patients, significantly less than the 250-nm resolution of light microscopy. We regard the leukemia in these three patients as comprising a distinct clinical, ultrastructural, and cytogenetic entity that we have chosen to call “microgranular” acute promyelocytic leukemia.

The Philadelphia (Ph1) chromosome results in a fusion of portions of the BCR gene from chromosome 22 and the ABL gene from chromosome 9, producing a chimeric BCR-ABL mRNA and protein. In lymphoblastic leukemias, there are two molecular subtypes of the Ph1 chromosome, one with a rearrangement of the breakpoint cluster region (bcr) of the BCR gene, producing the same 8.5-kilobase BCR-ABL fusion mRNA seen in chronic myelogenous leukemia (CML), and the other, without a bcr rearrangement, producing a 7.0-kilobase BCR-ABL fusion mRNA that is seen only in acute lymphoblastic leukemia (ALL). We studied the molecular subtype of the Ph1 chromosome in 11 cases of Ph1-positive ALL, including 2 with a previous diagnosis of CML, using a sensitive method to analyze the mRNA species based on the polymerase chain reaction (PCR). We observed unexpected heterogeneity in BCR-ABL mRNA in this population; in particular, 1 of 6 bcr-rearranged cases and 1 of 5 bcr-unrearranged cases contained none of the known fusion mRNA species, while 1 of the bcr-rearranged cases contained both. This latter case is particularly interesting because it suggests that the acquisition of an additional BCR-ABL fusion species may be a mechanism of disease progression. We conclude that the PCR gives additional information about the Ph1 chromosome gene products that cannot be obtained by genomic analysis, but that it cannot be used as the sole means of detection of this chromosomal abnormality in ALL because of the high incidence of false negative results.

Patients with acute lymphoblastic leukemia (ALL) who present with bulky disease of the lymph nodes, spleen, or mediastinum--so-called "lymphomatous ALL"--appear to represent a distinct subgroup among patients with ALL of T-cell lineage who have different clinical findings, but the biologic basis for these differences is not known. While studying 65 patients with lymphoblastic leukemia whose karyotype was determined at diagnosis, we compared the findings in 8 patients with lymphomatous ALL and 57 patients whose presentations were more typical of ALL. Six patients with lymphomatous ALL had karyotypic abnormalities leading to loss of bands p21-p22 on the short arm of chromosome 9. The mechanisms varied and included deletions, unbalanced translocations, or loss of the entire chromosome. Only 1 of the 57 patients without lymphomatous ALL had an abnormality of chromosome 9 at diagnosis (P less than 0.001). These findings indicate that loss of chromosomal material in the region of 9p21-p22 is closely associated with lymphomatous ALL; by analogy with retinoblastoma, in which gene deletions are associated with an enzyme deficiency, this disease may be related to the loss of the enzyme methylthioadenosine phosphorylase, previously reported in some of these patients.

Cytogenetic studies were performed on 26 patients who developed acute nonlymphocytic leukemia (ANLL) or a dysmyelopoietic syndrome after treatment of a primary malignancy. Fifteen patients had radiotherapy and chemotherapy, seven had only chemotherapy, and four had only radiotherapy. The median times from diagnosis of the initial disease to the development of bone marrow dysfunction for these treatment groups were 50, 46, and 49 mo, respectively. Twenty-five patients had an abnormal karyotype in myeloid cells. Loss of part or all of no. 5 and/or no. 7 was noted in 23 of 25 patients with aneuploidy. Loss of no. 5 was noted only in patients who previously had malignant lymphoma, whereas loss of no. 7 was seen in these patients as well as in those who had other malignancies. Abnormalities of both nos. 5 and 7 occurred in 53% of the patients treated with combined therapy and in only 27% of patients treated with either modality alone. Although these changes are distinctly different from those noted in lymphomas, they are similar to those seen in 25% of aneuploid patients with ANLL de novo.

Chromosomes from a patient with mycosis fungoides were examined in detail with banding techniques. Hyperdiploid cells from a lymph node had common anomalies of certain chromosomes which formed three similar clones. The abnormalities involved chromosomes No. 1, 2, 5, 8, 9, 10, 14, and 18, in addition to an unkwown small metacentric marker (M3). Although there were a number of mitotic cells in peripheral blood cultured both with and without PHA, none of the few cells with abnormal karyotypes was similar to the clonal cells of the lymph node. One of the abnormalities in the lymph node was a 14q rearrangement, which could be the result of a translocation of Nos. 8 and 14 involving a third chromosome, No. 2. An abnormality in the blood resulted from a translocation between the long arms of Nos. 1 and 14. These findings could be useful for studies in which mycosis fungoides is compared with the Sezary syndrome and other lymphoid malignancies.

Seventeen patients with therapy-related myelodysplastic syndrome (t- MDS) or therapy-related acute nonlymphocytic leukemia (t-ANLL) were treated with single-agent high-dose cytarabine (HDAC; 1 to 3 g/m2 every 12 hours for 12 doses). The initial neoplasm was still present in eight patients when t-MDS/t-ANLL developed. Fifteen of the 16 patients with chromosomal abnormalities in bone marrow cells had loss or rearrangement of chromosomes 5 and/or 7. One patient had a t(15;17), and one had inadequate material for cytogenetic analysis. Twelve patients had normal metaphase cells (3% to 71%). Indications for HDAC therapy were progressive pancytopenia in 13 patients or rising blast count in four. Five patients died of marrow hypoplasia following therapy. Four others had refractory t-ANLL and died within the subsequent 5 months. Only one of ten patients with a poor performance status (PS greater than or equal to 2 using the ECOG scale) achieved a complete remission, but all seven patients with a good performance status (PS less than or equal to 1) had a complete remission. Hematologic remissions were achieved in 8 patients (47%) after one (6 patients) or two (2 patients) induction courses and were confirmed by recovery of a 100% normal marrow karyotype in six of the seven patients who were retested. Patients in remission received one to four consolidation courses with HDAC alternating with cytarabine/doxorubicin, but seven relapsed within 8 months (median remission duration, 5 months). In every case, the original chromosomal abnormality reappeared at relapse. HDAC has a high response rate for good-performance patients with t-MDS/t-ANLL, but complete remissions are short even when confirmed cytogenetically and consolidated intensively.

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.

Chromosomes were studied in cells from tissues primarily involved by diffuse “histiocytic” lymphoma in nine patients. Two of the patients had stage II disease; their tumors were fibrotic and had no mitotic cells. One patient was in stage III, and the remaining six patients had stage IV disease. The modal chromosome number of abnormal cells from these last seven patients was hypodiploid in two, hyperdiploid in four, and near-triploid in one. Complete banding studies of six cases and partial analysis of the seventh indicate that (1) every patient had a distinct cell line with common markers, with a few cells showing minor variants; (2) although certain chromosomes (Nos. 1, 2, 3, 9, 12, and 14) were structurally affected more often than others, no markers with the same banding pattern were noted among them; and (3) the cytologic type of lymphoma could be correlated with the karyotype in all seven patients. When the Lukes and Collins classification was used, three patients whose tumors were composed predominantly of large noncleaved cells showed a 14q translocation leading to the formation of a 14q+ marker chromosome. This marker was not observed in four patients whose tumors had a majority of large cleaved cells. These preliminary results, if confirmed in a larger series of patients, will provide additional evidence that there are consistent chromosome changes associated with specific subtypes of lymphoproliferative disorders analogous to the Ph1 chromosome in chronic myelogenous leukemia.

A patient with a rapidly fatal hypereosinophilic syndrome and a bone marrow chromosomal abnormality, 49,XYY,t(3:5),+8,+mar, is described. Scanning and transmission electron microscopy of eosinophils failed to reveal any significant abnormalities. Previous cytogenetic data on patients with hypereosinophilic syndrome have been deficient in that few studies have been performed with banding technics. These technics may help in the classification of hypereosinophilic syndrome and predict which patients will have a rapidly fatal course.

Karyotypic abnormalities were detected in the malignant cells of 6 of 18 patients with multiple myeloma (MM). Six patients with benign monoclonal gammopathy, one with amyloidosis of immunoglobulin origin, and two with Waldenstrom's macroglobulinemia had normal karyotypes. All six MM patients with aneuploidy were in a group of 10 patients in an accelerated or relapse phase of their disease and four had high serum paraprotein levels (7.92, 6.24, 6.80, and 4.24 g/dl, respectively) when their abnormal karyotypes were detected. Five of the 6 MM patients with aneuploidy had received prior chemotherapy. Aneuploidy was not observed in 8 stable MM patients. Abnormalities of chromosome 14 were present in all 6 patients, with a 14q+ marker in 5 and loss of No. 14 in 1. A translocation between Nos. 11 and 14 was found in aneuploid cells of 2 patients who had plasma cell leukemia (PCL). However, the break point in the long arm of No. 11 differed in the 2 patients. A gain of Nos. 5, 9, and 11 was seen in 3 patients, a gain of No 1 in 2, and rearrangements of No. 1 in 5 MM patients, including all 4 who had a 14q+ marker chromosome initially. A deletion of chromosome 6 at band q25 was detected in 2 MM patients and a pericentric inversion of No. 6 (6p21 to 6q13) was seen in the patient with PCL. Three of 4 MM patients had a nonrandom loss of one chromosome 8. Two other MM patients, who were treated with melphalan and prednisone, developed acute nonlymphocytic leukemia (ANLL) 2+ and 4+ years after the diagnosis of MM. Marrow cells of one patient showed a 5q- chromosome and a constitutional translocation involving Nos. 13 and 14 during the preleukemic stage; during the leukemic phase, the karyotype evolved to 50 chromosomes including extra chromosomes 1, 6, 8, 10, and 21 and a missing 7, in addition to the originally detected 5q- and the 13/14 translocation. The peripheral blood from the other patient was hypodiploid, with a missing chromosome 7 and a translocation between 3q and 9p. These patterns of chromosome change resemble those of ANLL rather than MM and are similar to the changes seen in ANLL after treated malignant lymphoma.

A splenectomized patient with hairy cell leukemia (HCL) who had received chemotherapy with a low-dose alkylating agent for 2 years developed dysmyelopoietic syndrome (DMPS), the first such case to be described. A portion of his marrow remained chronically involved with HCL, but the remainder evolved from being morphologically and karyotypically normal to involvement with DMPS, with cells having a bizarre karyotype. Three of four metaphase cells had consistent abnormalities, with a missing chromosome No. 5, structural rearrangements resulting in deletion of part of the long arm of chromosome No. 7, deletion of 2q, and a small ring chromosome; upon further clonal evolution, a translocation between chromosomes No. 12 and 15 and deletion of the long arm of chromosome No. 19 were seen. We therefore add HCL patients to the growing list of those at risk of developing a secondary hematologic malignant disease possibly due to cytotoxic therapy for their primary disorder.

A group of 18 patients with acute nonlymphocytic leukemia and the chromosomal aberration monosomy 7 in their bone marrow cells was compared to a group of control patients with the same disease but normal bone marrow chromosomes. The monosomy 7 group of patients had a higher incidence of fever and infections, and a higher white blood cell and granulocyte count compared to the control group at the time of diagnosis. The clinical difference between the groups continued over the first month of hospitalization. Complete remission was obtained in 12% of the monosomy 7 group and in 59% of the control group. Survival was clearly longer in the control group of patients. Monosomy 7 of the bone marrow in acute nonlymphocytic leukemia is therefore to be considered a bad prognostic sign.

Inv(16)(p13q22) and t(16;16)(p13;q22) are recurring chromosomal rearrangements which juxtapose the metallothionein gene cluster at 16q22 with other DNA sequences from 16p13. We have studied 20 men and 13 women who had acute nonlymphocytic leukemia; 27 patients had an inv(16) and six patients had a t(16;16). Eight patients also had trisomy 22, and four had trisomy 8. All but two patients had the unique morphologic features of acute myelomonocytic leukemia with abnormal eosinophils (M4Eo). In one patient with M4 leukemia, abnormal eosinophils were not observed in the marrow. A second patient had acute monocytic leukemia, plus abnormal eosinophils. Eosinophils constituted 1% to 46% (median, 6%) of the bone marrow cells, and in all but a single patient, the eosinophils exhibited distinctly abnormal morphology. Twenty-five patients have had a complete remission (78% of treated patients). Nine patients have remained in remission longer than 24 months. No patient had symptoms of central nervous system (CNS) disease at diagnosis, and none had CNS leukemic mass lesions at any time. Treatment with high-dose cytarabine may have provided prophylactic CNS therapy. Four additional patients with chromosomal rearrangements involving a breakpoint at 16q22 but not at 16p13 have had different morphological features and different clinical courses. Thus, the juxtaposition of genes at 16p13 and 16q22, which occurs both in the inv(16) and the t(16;16), results in a specific subset of acute nonlymphocytic leukemia that has a favorable prognosis.

An insertion (10;11)(pl1;q23q24) was found in bone marrow metaphase cells from two children with acute monocytic leukemia (AMoL-M5b). This rearrangement involves a small chromosomal segment of 11q and may be misinterpreted as a deletion of 11q. Insertion (10;11) may represent a new recurring abnormality involving 11q associated with acute leukemia of the M5b type.

Acute nonlymphocytic leukemia associated with the chromosomal translocation t(6;9)(p23;q34) is an entity that is frequently associated with basophilia, which it shares with chronic myelogenous leukemia. The breakpoint on chromosome 9, q34, appears to be cytogenetically identical in both malignancies and is the site of the cellular oncogene c-abl. We investigated the role of c-abl in cells from two patients with the t(6;9) using in situ chromosomal hybridization, Southern hybridization, and in vitro phosphorylation. We showed that c-abl is not translocated from chromosome 9, resulting in a breakpoint that is on the 3' side of this gene. The t(6;9) translocation does not appear to result in the production of an aberrantly sized protein product or in the acquisition of in vitro tyrosine kinase activity. This is in direct contrast to the findings in chronic myelogenous leukemia, in which c-abl is translocated, leading to the production of a structurally altered c-abl protein with activated tyrosine kinase. Lastly, we demonstrated that the cells of one patient contain sequences from chromosome 9 inserted at the junction of a reciprocal translocation between chromosomes 4 and 10 on the 4q+ chromosome. This insertion, which is at least 100 kilobase pairs in length, represents a duplication and translocation of the protein coding region of c-abl.

Less information is available on the cytogenetic abnormalities in marrow cells of patients with acute lymphoblastic leukemia (ALL) than on abnormalities in acute nonlymphocytic leukemia (ANLL); nonetheless, some patterns of karyotypic change in ALL are evident. Even with banding, about 50% of patients appear to have a normal karyotype. The modal chromosome number tends to be higher in ALL than in ANLL. Every patient with B-cell ALL has had an abnormality of one chromosome No. 14 that involved the translocation of material to the end of the long arm. Among seven reported cases, the translocation was from 8q in three patients and 11q in one. Cells with a haploid or near-haploid (24 to 35) chromosome number have been reported in five patients with ALL and in four patients in a lymphoid blast crisis of chronic myelogeneous leukemia. The karyotype in the four ALL patients whose cells were analyzed with banding was remarkably consistent. All patients had the haploid number, usually with both sex chromosomes, plus an additional No. 10, 18, and 21. Evolution of the karyotype, which occurs in the leukemic cells of about 50% of patients, involves cells of patients who had an initially normal or an initially abnormalmore » karyotype. The evidence regarding a correlation between the presence of an abnormal clone prior to treatment and response to treatment is contradictory at present. Some chromosome abnormalities, such as the presence of a Philadelphia (Ph/sup 1/) chromosome, a 14q+chromosome, or a haploid clone, are associated with a relatively short survival.« less

A 22-yr-old man with acute myelocytic leukemia received a bone marrow transplant from a genotypically HLA-identical female sibling after cyclophosphamide preparation. He remained in complete remission for 18 mo, when he developed a chloroma in the perineum. The chloroma was treated with local radiotherapy. The chloroma recurred 8 mo later and was treated with radiotherapy followed by combination chemotherapy. At 34 mo after transplant, marrow relapse and chloroma were documented. The first chloroma contained host cells by fluorescent Y-chromatin body analyses of interphase nuclei. All metaphase cells and karyotypes from peripheral blood and marrow samples showed no evidence of host cells from 3 wk after transplant through the time of marrow relapse. Data from autosomal and sex chromosome studies indicate that the marrow relapse occurred in cells of donor origin. A new consistent chromosome abnormality [45, X, -X, t(8;21) (q22; q22)] was observed in a majority of donor cells. The patient received a second bone marrow transplant from the same donor after preparation with busulfan and cyclophosphamide and attained a complete remission with full hematologic engraftment.

Chromosome banding patterns were obtained for 50 of 55 consecutive adult patients with acute nonlymphocytic leukemia during a 5-yr period. Twenty-two of the 50 cases were diagnosed as acute myelocytic leukemia (AML), 24 as acute myelomonocytic leukemia (AMMol), 2 as acute promyelocytic leukemia (APL), and 2 as erythroleukemia. Twenty-five patients had initial chromosome abnormalities during the course of the disease. The median survival of patients with normal chromosomes initially (group I) was 10 mo, whereas that of patients with abnormal chromosomes initially (group II) was 2 mo. Similar times were obtained for treated patients with AML and AMMol. However, when the AML patients were separated into those with and those without a chromosome abnormality, the median survival times were markedly different (2 mo versus 18 mo, respectively). Patients with AMMol demonstrated no difference in median survival times when subgrouped according to the presence or absence of chromosome abnormalities. The treated group II patients whose marrow samples had only abnormal metaphases had a poorer response (10% complete remission) and median survival (2 mo) than the group II patients who had at least one normal metaphase (42% complete remission with a median survival of 9 mo). The two cases of APL demonstrated a deletion of the long arm of No. 17 which occurred in the same region of the chromosome in each case. Both patients had similar clinical histories, with disseminated intravascular coagulation, and neither responded to therapy.

Cytogenetic specimens were obtained from blood or bone marrow in 27 patients with acute promyelocytic leukemia, including four with the microgranular variant. A 15;17 translocation was identified in 21 to 100 percent of metaphase cells from all 27 patients. The structural rearrangement was identical in every case, and the breakpoints were assigned to 15q22 and 17q21.1. Twelve patients had complete remission, and two (both with the microgranular variant) have had unmaintained continuous remission longer than four years. These data indicate that the 15;17 translocation may be found in every patient with acute promyelocytic leukemia if optimal chromosome analysis is performed.

Six of eight (75%) patients with postpolycythemic myelofibrosis (PPMF) and 11 of 20 (55%) patients with idiopathic myelofibrosis (MF), seen at the University of Chicago, had abnormal karyotypes in cells of bone marrow origin. The specific chromosomal findings and their clinical significance in these patients were analyzed. A review of the literature added the findings from abnormal karyotype studies in 10 patients with PPMF and 36 patients with MF to this series. The demonstration of an increased frequency of cytogenetic abnormalities after cytotoxic therapy in polycythemia vera (PV) implies that such therapy may have a role in the development of chromosomal changes seen in treated PV and PPMF. The cytogenetic abnormalities in MF appear to be unrelated to therapy except possibly for an association with partial or complete losses of chromosome 5 or 7. Trisomy 8 is the only finding that is more common in MF than in PPMF. Other abnormalities were more common in PPMF, particularly 20q-, loss of 7 or 7q-, and trisomy 9, and to a lesser extent trisomy 1q and 5q-. Cytogenetic abnormalities do not show a pattern that can be used to distinguish between PPMF and MF, nor are they useful in the prognosis of MF or in initial studies in PPMF. PPMF does appear to have a higher tendency toward leukemic transformation than does MF, and an evolution in karyotype appears to have serious prognostic implications in PPMF in regard to this transition.

Cytogenetic, pathologic, and immunologic studies were done on 10 patients with lymphoblastic lymphoma (LL). The median age was 21 years, and males predominated in a ratio of 9:1. At the time of diagnosis, 6 of the 10 patients had an anterior mediastinal mass, 3 had bone marrow involvement, and 2 had central nervous system involvement. All patients were treated with intensive combination chemotherapy. The median survival of the 8 patients who died (7 of whom were adults) was 10.5 months; all 8 achieved only a partial remission. Two other patients were children; they continue in complete remission. Immunologic marker studies were done on 9 of the patients; 5 had T-cell LL, and the other 4 had non-T, non-B LL. In a study of T-cell subpopulations with the use of monoclonal antibodies, the malignant T cells of the 2 patients tested appeared to be mature thymocytes. Clonal chromosome abnormalities were seen in involved tissues from 8 patients; the other 2 patients had a normal karyotype. A 9q+ chromosome, a 6q- chromosome, and a 1q-chromosome associated with 1q trisomy were each seen in 2 patients. No patients had a 14q+ chromosome, which is the most common abnormality in various lymphoproliferative disorders, including other T-cell malignant diseases. The variable chromosome pattern in LL could be related to the heterogeneity of the immunologic phenotype of the malignant T cells. More data are needed before it can be established whether there are any correlations between a particular karyotype and the immunologic phenotype of LL cells.

An identical reciprocal translocation between the long arms of chromosomes 3 and 21 with breakpoints in bands 3q26 and 21q22, t(3;21)(q26;q22), was found in three male patients with the blast phase of chronic myelogenous leukemia (CML). The abnormality was clonal in all three patients and was always accompanied by either a standard or variant 9;22 translocation resulting in a Philadelphia chromosome (Ph1). In two cases, the t(3;21) was the only abnormality other than a t(9;22) in the primary clone. Serial studies of one patient demonstrated that the t(3;21) occurred as a result of clonal evolution near the time of development of the blast phase. We have not observed the t(3;21) in greater than 500 patients with CML in the chronic phase. Thus, the t(3;21) is a new recurring cytogenetic abnormality associated with the blast phase of CML.

Forty-nine patients with primary myelodysplastic syndromes (MDS) were subclassified according to French-American-British (FAB) Cooperative Group criteria. Eight patients had acquired idiopathic sideroblastic anemia (AISA), ten had chronic myelomonocytic leukemia (CMMoL), 14 had refractory anemia (RA), nine had refractory anemia with excess blasts (RAEB), and five had refractory anemia with excess blasts in transformation (RAEB-T); three patients could not be subclassified. The actuarial median survival for patients with AISA or with RA had not been reached at 60 months of follow-up. The median survival times for patients with CMMoL, RAEB, and RAEB-T were 25, 21, and 16 months, respectively. The percentages of patients with each subtype who developed ANLL were none in AISA, 20% in CMMoL, 7% in RA, 56% in RAEB, and 40% in RAEB-T. Patients with CMMoL had a poor prognosis independent of transformation to acute nonlymphocytic leukemia (ANLL), whereas patients with RAEB and RAEB-T had a high incidence of transformation and short survival times. Clonal chromosomal abnormalities were present in bone marrow cells from 19 patients at the time of diagnosis, and two others developed an abnormal karyotype at the time of leukemic transformation. The most frequent abnormalities, including initial and evolutionary changes, were trisomy 8 (9 patients), deletion of 5q (4 patients), and deletion of 20q (4 patients). The median survival times were 32 months for patients with an abnormal karyotype, and 48 months for those with a normal karyotype (P = 0.2). Specific chromosomal abnormalities were not associated with particular histologic subtypes; however, a high percentage of patients with RAEB and RAEB-T had an abnormal clone (89% and 80%, respectively). The percentages of patients with clonal abnormalities were 13% for AISA, 20% for CMMoL, and 29% for RA. The MDS transformed to ANLL in 42% of patients with an abnormal karyotype, compared to 10% of those with an initially normal karyotype (P less than .01). Among patients with RA, RAEB, and RAEB-T, the risk of leukemic transformation was confined to those with an abnormal karyotype (P less than .01). Thus, in the present study, morphology and karyotype combined were the best indicators of outcome in patients with MDS.

The renewed interest in the study of chromosome abnormalities in hematologic malignancies, particularly in the leukemias, is the result of technical improvements which permit the precise identification of each human chromosome, and of parts of chromosomes as well. The information obtained raises a number of questions regarding the validity of older notions, such as the variability of the chromosome pattern (karyotype) in acute leukemia, or the rarity of associations of specific chromosome abnormalities with particular types of leukemia. One of the surprising observations of the last few years has been the frequent occurrence of consistent translocations in a variety of hematologic malignancies. The challenging questions at present are how and why nonrandom changes, particularly consistent translocations, occur.