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CD8-depleted donor lymphocyte infusion as treatment for relapsed chronic myelogenous leukemia after allogeneic bone marrow transplantation.

Donor lymphocyte infusions can reinduce complete remission in the majority of patients with chronic myelogenous leukemia (CML) who relapse into chronic phase after allogeneic bone marrow transplantation (BMT). Such infusions are associated with a high incidence of graft-versus-host disease (GVHD) and marrow aplasia. BMT using selective depletion of CD8+ lymphocytes from donor cells reduces the incidence of GVHD without an increase in leukemia relapse. We hypothesized that infusion of CD8-depleted donor peripheral blood lymphocytes could also reinduce complete remissions with a lesser potential to produce symptomatic GVHD in patients with CML who relapsed after allogeneic BMT. Ten patients with Ph(+) CML who relapsed a median of 353 days after BMT (range, 82 to 1,096 days) received donor lymphocyte infusions depleted of CD8+ cells. Nine patients received a single infusion and 1 received two infusions. Four patients were treated while in chronic phase with clonal evolution, 2 during accelerated phase, 3 during blast crisis, and 1 in a cytogenetic relapse. A mean of 0.9 +/- 0.3 x 10(8) mononuclear cells/kg were infused, containing 0.6 +/- 0.4 x 10(6) CD3+CD8+ cells/kg. Six patients achieved hematologic and cytogenetic remission at 4, 8, 11, 15, 39, and 54 weeks after lymphocyte infusion. Two patients developed > or = grade II acute GVHD, and 1 patient developed mild chronic GVHD. We conclude that donor lymphocyte infusions depleted of CD8+ cells can induce remissions with a low rate of severe acute GVHD in patients with CML who relapse after allogeneic BMT, supporting the hypothesis that CD8+ lymphocytes are important effectors of GVHD, but may not be essential for the graft-versus-leukemia effect against this disease. Further controlled studies are required to confirm these preliminary observations.

Acute Disease↗

Differential effects of TGF-beta 1 on normal and leukemic human hematopoietic cell proliferation.

We evaluated the effects of transforming growth factor-beta 1 (TGF-beta 1) on the growth of hematopoietic progenitors in normal donors and in patients with hematologic malignancies now designed as clonal disorders of multipotential stem cells. TGF-beta 1 at 80 pM exhibited differential effects on the normal hematopoietic progenitors when cells were stimulated with different growth factors, such as G-CSF, GM-CSF, interleukin-3 (IL-3), or stem cell factor (SCF). The suppressive effect by TGF-beta 1 was increased for growth with GM-CSF, IL-3, and SCF, and growth with G-CSF was unaffected in hematologic malignancies, TGF-beta 1 suppression for growth with G-CSF was increased for essential thrombocythemia (ET) and polycythemia vera; chronic myelogenous leukemia (CML) in chronic phase; CML in accelerated phase; CML in myeloid crisis; myelodysplastic syndrome (MDS) in refractory anemia; MDS in refractory anemia with an excess of blasts; and acute myeloblastic leukemia (AML). In CML-myeloid crisis and AML, TGF-beta 1 almost completely abolished the growth, with some patient-to-patient variation. The mean ED50s for the growth of leukemic blast progenitors were 1.6, 1.2, 0.7, and 0.2 pM in the presence of G-CSF, GM-CSF, IL-3, and SCF, respectively, c-myc and c-myb antisense oligonucleotides significantly suppressed the growth of leukemic blast progenitors, but not that of clonogenic cells from normal donors and patients with ET. We also demonstrated that TGF-beta 1 inhibits mRNA expression by AML blasts for c-myc and/or c-myb. When the data are taken together, growth suppression by TGF-beta 1 appears to increase with the progression of clonal evolution in hematologic malignancies.

Base Sequence↗

Prolonged persistence of PCR-detectable minimal residual disease after diagnosis or first relapse predicts poor outcome in childhood B-precursor acute lymphoblastic leukemia.

The follow up of minimal residual disease (MRD) in childhood B-precursor ALL by polymerase chain reaction (PCR) may be of help for further stratification of treatment protocols, to improve outcome. However, the clinical relevance of this approach has yet to be defined. We report the retrospective follow-up of MRD in bone marrow (BM) samples from 50 childhood B-precursor ALL patients by IgH/TCR delta PCR. Twenty-two patients remained in continuous complete remission (median follow-up 61 months), and 28 experienced relapse (median follow-up 75 months). Initial regression of MRD on therapy correlated with outcome. At the end of induction therapy 2/18 (11.1%) patients from the CCR group were PCR positive vs 10/16 (62.5%) from the 'relapse' group (P = 0.005). The presence of PCR detectable MRD predicted event-free survival independent of standard clinical and cytogenetical parameters. Also subsequent to first BM relapse, a correlation between MRD regression and outcome was observed. Six of eight patients who became PCR negative in the time period between relapse and bone marrow transplantation are in CCR, whereas 7/7 patients who remained PCR positive in this time period died (P = 0.006). In approximately 70% of evaluable patients, clinical relapse was preceded by recurrence of detectable MRD at time intervals of 3-18 months earlier and the recurrence of PCR positivity after a period of negativity was always followed by overt relapse. At relapse, the combined use of IgH and TCR delta probes reduced false negativity caused by clonal evolution to approximately 10%. This study shows that the evolution of PCR detectable MRD is an independent predictor of outcome.

Adolescent↗

Fluorescent in situ hybridization and cytogenetic studies of trisomy 12 in chronic lymphocytic leukemia.

Cytogenetic studies (CG) of 475 chronic lymphocytic leukemia (CLL) cases showed trisomy 12 in 6.1% or 26% of patients with abnormal karyotypes. Fluorescence in situ hybridization (FISH) detected trisomy 12 in 35% of 117 CLL patients. Only 34.6% of cases detected by FISH were detected by CG. Twelve patients had low levels of trisomic cells (4% to 11%) relative to clonal B cells (47.5% to 86%), suggestive of clonal evolution. Untreated patients with trisomy 12 were predominantly male (P < .05) and had an increased incidence of splenomegaly (P < .03). Patients with trisomy 12 were more likely to be previously treated and had advanced Binet stage compared with those without trisomy 12. The median survival was shorter in patients with trisomy 12 (7.8 years) and patients with other chromosomal abnormalities without trisomy 12 by FISH (5.5 years) than in patients with diploid karyotypes (14.4 years). The response to fludarabine was similar to that of patients with diploid karyotypes, but there was a trend for earlier disease progression. FISH detected residual disease in all patients with trisomy 12 in complete (n = 6) or partial remission (n = 4). As few as 1 trisomic cell in 5,000 was detected by performing FISH on fluorescence-activated cell sorter-sorted cells. Trisomy 12 was absent in T cells in patients with trisomy 12. We conclude that FISH identifies trisomy 12 approximately 2.6 times more often than CG, readily identifies minimal residual disease, and predicts for a shorter median survival.

Antigens, CD↗

Detection of aneuploidy and polyploidy in non-Hodgkin's lymphoma by computer video image analysis.

Thirty-six cases of histologically intermediate and low grade non-Hodgkin's lymphoma, classified according to the International Working Formulation, were examined using image analysis cytometry. Aneuploidy was detected in 21 cases (58%). No significant difference in either the incidence or extent of aneuploidy was seen for cases that entered remission when compared to cases that did not. Bone marrow examinations, by either aspiration or trephine biopsy, were conducted on 34 cases, with 11 showing lymphocytic infiltration. Aneuploidy was detected in 6 of the 11 cases having bone marrow involvement, while 5 cases with bone marrow infiltration were euploid. Polyploid cell distributions were detected in 3 cases, and the remaining 12 cases were diploid. The biologic significance of polyploidy among non-Hodgkin's lymphomas is not well understood, and its detection is limited to static techniques for DNA quantitation. With further investigation, awareness of its presence may reveal some insight into the clonal evolution of this neoplasm.

Adolescent↗

Genomic instability and the role of p53 mutations in cancer cells.

The p53 tumor-suppressor gene encodes a cell-cycle checkpoint protein that functions in the G1 phase of the cell cycle. When DNA damage is incurred, p53 transactivates a number of downstream genes whose products, with diverse biologic activities, each make a contribution to the cellular response to DNA damage. One major p53-mediated stress response is the G1 cell-cycle arrest, or delay, which probably allows the cell time to repair DNA damage prior to S-phase entry. In cells lacking p53 function, which include most cancer cells, a condition of genomic instability results from checkpoint loss that culminates in gene amplifications, aneuploidy, and other chromosomal aberrations. These abnormalities contribute to the clonal evolution of cancer cells and tumor progression. The role of p53 in radioresistance and chemoresistance is discussed.

Animals↗

Basophilic differentiation in acute promyelocytic leukemia.

A rare variant of acute promyelocytic leukemia (APL) is associated with basophilic differentiation. Such a patient presented with basophilia, headaches, and diffuse engorgement of superficial blood vessels, attributable to hyperhistaminemia. Karyotype analysis showed a clonal rearrangement of chromosome 12p13 in addition to the t(15;17). During treatment with all-trans-retinoic acid (TRA), the absolute basophil count rose steadily during the first week, then declined. By one month, the basophilia resolved, an abrupt rise occurred in both the platelet and absolute neutrophil count, and the bone core biopsy showed complete maturation of all cell lines. Abnormalities of chromosome 12p13 in acute myelogenous leukemia have been associated with basophilia. Since every cell in our patient with t(12p13;?) also had the t(15;17), we speculate that the basophilia was due to clonal evolution with acquisition of the t(12p13;?). In two out of five other reported cases, abnormalities of chromosomes known to be associated with basophilia were present in addition to t(15;17). It is possible that the basophilia in this variant is reactive; however, since TRA induces differentiation of leukemic promyelocytes into mature neutrophils, we speculate that the leukemic promyelocytes in our patient differentiated into basophils. Future studies employing either fluorescent in situ hybridization or polymerase chain reaction using a probe to the breakpoint on t(15;17) may establish whether or not the basophils derive from the leukemic clone.

Adult↗

[Detection of minimal residual disease by means of FISH and PCR methods and its clinical evaluation].

The monitoring of MRD by FISH and PCR is now clinically evaluated for a prediction of the relapse of leukemia. However, these methods include several technical limitations. In FISH, an appropriate cut off value should be settled for each probe or procedure in estimating chromosomal gain, loss, or translocation and the sensitivity depends on the cut off values but it may reach to 10(-3). In PCR, the sensitivity is higher than that of FISH especially using genomic DNA as a template. However, the detection of chromosomal translocation-specific DNA or RNA constructs is currently applicable to limited cases and the amplification of Ig or TCR gene rearrangement has a major pitfall caused by the clonal evolution. Clinically, MRD can be an indicator for a prediction of the relapse. For example, a greater MRD on entering CR tends to be related with an early relapse, a return to MRD-positive after disappearance of MRD will be a sign of impending relapse, and MRD negativity at the termination of therapy may be correlated with a long-term disease free status. More precise evaluation of MRD is necessary with regard to therapeutic strategy.

Humans↗

Development of surrogate endpoint biomarkers for clinical trials of cancer chemopreventive agents: relationships to fundamental properties of preinvasive (intraepithelial) neoplasia.

The tissue changes offering the greatest immediate potential for development as surrogate endpoint biomarkers (SEBs) to be used in Phase II trials of cancer chemopreventive agents are those derived from the microscopic tissue changes pathologists use to make the diagnosis of preinvasive (intraepithelial) neoplasia. These changes comprise four categories: proliferative index, ploidy, nuclear morphometry (size, shape, texture, and pleomorphism), and nucleolar morphometry (number, size, shape, position, and pleomorphism). Computer-assisted image analysis (CIA) permits dozens of additional morphometric parameters to be developed. Other categories of candidate SEBs are: DNA and chromosomal structural changes associated with genomic instability, activation of oncogenes and inactivation of tumor suppressor genes, structural changes in differentiated molecules, and aberrations of growth factor/receptor structure and function. Self-perpetuating DNA breakage with secondary mutator mutations in genomic stability genes is a major mechanism by which the genomic instability characteristic of neoplasia occurs, and from which stem other basic neoplastic properties, including clonal evolution, along multiple pathways of genetic variation that are stochastically determined, continuously increasing proliferation, rate and extent of phenotypic heterogeneity. SEBs resulting from genomic instability include homogeneously staining regions, double minute chromosomes, micronuclei, dicentrics, gene amplification, loss of heterozygosity, and alterations in chromosome number. Newly developed assays for detecting genomic instability include comparative genomic hybridization using fluorescence in situ hybridization on > 20 micron-thick sections monitored by confocal laser scanning microscopy, assays for microsatellite instability, and restriction landmark genomic scanning. These assays offer promise for detecting the earliest molecular changes of neoplasia in normal-appearing epithelium prior to the onset of the dysplastic phase of intraepithelial neoplasia.

Anticarcinogenic Agents↗

Minimal residual disease after bone marrow transplantation for multiple myeloma: evidence for cure in long-term survivors.

Allogeneic bone marrow transplantation (BMT) can induce long-term complete remission (CR) in patients with multiple myeloma but it is not yet clear whether the disease can be eradicated. We have used immunoglobulin gene fingerprinting, a PCR-based technique, to evaluate minimal residual disease in 5 patients in unmaintained CR 9-60 months after allogeneic BMT. All 5 patients were PCR-positive within the first year after BMT, suggesting that early PCR positivity is common and not predictive of relapse. Three patients were studied at > 1 year post-transplant; one had become PCR-negative at 1 year, a second at 2 years and the third at 4.5 years post-BMT. The ability of the technique to detect clonal evolution was demonstrated by serial studies in a further patient who relapsed post-BMT. The absence of any detectable disease at the molecular level in 3 patients in long-term CR post-transplant suggests that cure of multiple myeloma may be a realistic goal.

B-Lymphocytes↗

Biological consequences of p160v-abl protein tyrosine kinase activity in a primitive, multipotent haemopoietic cell line.

A temperature sensitive abl protein tyrosine kinase gene was transferred into a multipotent haemopoietic stem cell line, and the primary biological effects of expression of the gene were examined at the permissive and non-permissive temperatures. Unlike previous studies in factor-dependent cell lines, we found that expression of the functional abl protein tyrosine kinase did not lead to growth autonomy. Furthermore, the cells were still able to undergo terminal myeloid differentiation. However, expression of the functional gene did lead to a delay in maturation with a concomitant increase in cell production, had a modest effect in terms of delayed apoptosis particularly when the cells were maintained at a high cell density, and slightly increased the response to sub-optimal concentrations of IL-3. In many respects, therefore, the effects of abl protein tyrosine kinase in these cells mimics the effect of bcr/abl in primary haemopoietic cells where growth factor independence and an aberrant differentiation profile are relatively late events in clonal evolution and are not intermediate consequences of activation of the abl gene.

Apoptosis↗

Richter's transformation of chronic lymphocytic leukemia with Hodgkin's-like cells is associated with Epstein-Barr virus infection.

The appearance of a high-grade lymphoma in the setting of B-cell chronic lymphocytic leukemia (CLL) is termed Richter's syndrome. Usually the high-grade component is a monomorphous, large cell lymphoma, but occasionally the high-grade component takes the form of Hodgkin's disease or a Hodgkin's-like lymphoma. Although Richter's syndrome is thought to represent clonal evolution of the underlying B-cell neoplasm in most cases, such a progression is difficult to explain when the high-grade component is Hodgkin's disease. We report two cases of Richter's syndrome in which the large cells had a morphology consistent with Reed-Sternberg cells and were found in a background of CLL. The large cells in both cases expressed the CD15 and CD30 antigens in a pattern characteristic of Reed-Sternberg cells, and the large cells in one case also expressed monotypic cytoplasmic immunoglobulin of the same type as that expressed by the underlying CLL. In both cases, Southern blot analysis of DNA from lymph nodes that contained both CLL and the Hodgkin's-like component showed single immunoglobulin gene rearrangements. Using the polymerase chain reaction, we found Epstein-Barr virus DNA in lymph nodes from both cases, and in peripheral blood lymphoid cells from one case 4 yr before the onset of Richter's syndrome. Immunoperoxidase staining showed expression of EBV latent membrane protein only in the Reed-Sternberg-like cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Analysis of Ig and T-cell receptor genes in 40 childhood acute lymphoblastic leukemias at diagnosis and subsequent relapse: implications for the detection of minimal residual disease by polymerase chain reaction analysis.

The rearrangement patterns of Ig and T-cell receptor (TcR) genes were studied by Southern blot analysis in 30 precursor B-cell acute lymphoblastic leukemias (B-ALLs) and 10 T-ALLs at diagnosis and subsequent relapse. Eight precursor B-ALLs appeared to contain biclonal/oligoclonal Ig heavy-chain (IgH) gene rearrangements at diagnosis. Differences in rearrangement patterns between diagnosis and relapse were found in 67% (20 cases) of precursor B-ALLs (including all eight biclonal/oligoclonal cases) and 50% (five cases) of T-ALLs. In precursor B-ALLs, especially changes in IgH and/or TcR-delta gene rearrangements were found (17 cases), but also changes in TcR-beta, TcR-gamma, Ig kappa, and/or Ig lambda genes (11 cases) occurred. The changes in T-ALLs concerned the TcR-beta, TcR-gamma, TcR-delta, and/or IgH genes. Two precursor B-ALLs showed completely different Ig and TcR gene rearrangement patterns at relapse, suggesting the absence of a clonal relation between the leukemic cells at diagnosis and relapse and the development of a secondary leukemia. The clonal evolution in the other 23 ALL patients was based on continuing rearrangement processes and selection of subclones. The development of changes in Ig and TcR gene rearrangement patterns was related to remission duration, suggesting an increasing chance of continuing rearrangement processes with time. These immunogenotypic changes at relapse occurred in a hierarchical order, with changes in IgH and TcR-delta genes occurring after only 6 months of remission duration, whereas changes in other Ig and TcR genes were generally detectable after 1 to 2 years of remission duration. The heterogeneity reported here in Ig and/or TcR gene rearrangement patterns at diagnosis and relapse might hamper polymerase chain reaction (PCR)-mediated detection of minimal residual disease (MRD) using junctional regions of rearranged Ig or TcR genes as PCR targets. However, our data also indicate that in 75% to 90% of ALLs, at least one major rearranged IgH, TcR-gamma, or TcR-delta band (allele) remained stable at relapse. We conclude that two or more junctional regions of different genes (IgH, TcR-gamma, and/or TcR-delta) should be monitored during follow-up of ALL patients for MRD detection by use of PCR techniques. Especially in biclonal/oligoclonal precursor B-ALL cases, the monitoring should not be restricted to rearranged IgH genes, but TcR-gamma and/or TcR-delta genes should be monitored as well, because of the extensive changes in IgH gene rearrangement patterns in this ALL subgroup.

Adolescent↗

Molecular detection and characterization of clonal cell populations in acute lymphocytic leukemia by analysis of conformational polymorphisms of cRNA molecules of rearranged T-cell-receptor-gamma and immunoglobulin heavy-chain genes.

Junctional regions of rearranged T-cell-receptor-gamma (TCR) and immunoglobulin heavy-chain (IgH) genes represent an idiotypic DNA sequence for an individual lymphocytic cell, and any clone or clonal disease developing from this cell. In this study, a novel methodology for detection and characterization of clone specific DNA sequences in patients with acute lymphocytic leukemia (ALL) was developed. Junctional regions of rearranged TCR-gamma IgH genes in specimens of bone marrow aspirates of patients with ALL (precursor-B-ALL ten, T-ALL two, null-ALL one; ALL not classified one), of a patient with lymphoid blast crisis of chronic myeloid leukemia, of a B-cell chronic lymphocytic leukemia, and in DNA from peripheral blood mononuclear cells of ten healthy volunteers were amplified by polymerase chain reaction (PCR). The PCR products were transcribed into complementary RNA (cRNA). Conformational polymorphisms of cRNA molecules were analyzed by non-denaturing polyacrylamide gel electrophoresis. A specific cRNA banding pattern for rearranged TCR-gamma or IgH genes was observed in all patients with lymphocytic leukemia. In contrast, analysis of DNA from healthy volunteers yielded a smear of confluent polymorphisms representing multiple different cRNA molecules. In two patients with precursor-B-ALL, cRNA banding patterns of junctional regions of rearranged TCR-gamma genes were analyzed in sequential bone marrow aspirates. The banding patterns disappeared after chemotherapy and achievement of blast clearance. This novel and rapid molecular assay offers several advantages as compared to Southern blot analyses and previous PCR based methodologies for the detection of clonal lymphocytic populations. With this methodology, studies on the clonal evolution of lymphoproliferative disorders (e.g. the prognostic significance of the emergence of additional clones) can be performed more easily than with any other traditional molecular method.

B-Lymphocytes↗

Anaplastic (sarcomatoid) carcinoma of the thyroid gland.

Anaplastic (sarcomatoid) carcinomas of the thyroid gland (ACT) seem to be decreasing in frequency. During the past 45 years, a threefold to fourfold diminution in the number of ACT cases has been seen internationally. Despite this fact, these tumors continue to pursue a lethal course in virtually all cases. Clinically, ACT are characterized by rapidly growing neck masses, often in patients who have had long-standing thyroid nodules or goiters. Microscopically, ACT shows a mixture of fusiform and pleomorphic tumor cells, with widespread permeation of surrounding cervical tissues. Osteoclast-like giant cells, intranuclear cytoplasmic invaginations, and divergent differentiation into chondro-osseous, vascular, or myogenic tissues also may be observed in ACT histologically. The common presence of admixed foci of differentiated thyroid cancer in ACT suggests that the latter neoplasm arises through the mechanism of "clonal evolution." Keratin is observed immunohistologically in roughly 80% of cases, further supporting this contention. Because the incidence of ACT has inversely paralleled increasing use of thyroid surgery in general, it may be hypothesized that early removal of hyperplastic or neoplastic thyroid tissue aborts the previously mentioned "dedifferentiation" phenomenon.

Adult↗

Malignant rhabdoid tumors: a clinicopathologic review and conceptual discussion.

The malignant rhabdoid tumor (MRT) has been a controversial lesion since its seminal description. There is no consensus as to whether it represents a distinctive clinicopathological entity or, alternatively, a phenotypic pattern that is potentially common to several disparate neoplasms. MRT of the kidney is a childhood tumor that is associated with uniformly aggressive behavior, but it shows a wide spectrum of histologic, immunophenotypic, and cytogenetic findings. Malignant extrarenal rhabdoid tumors (MERTs) have been observed in pure form over a broader range of patient ages and anatomic locations, but they show substantial morphological and biological homology with renal MRT. Lastly, "composite" extrarenal rhabdoid tumors (CERTs)--in which recognizable "parent" neoplasms are admixed with MERTs--also have been recognized in several topographic sites. In aggregate, these observations suggest that "rhabdoid tumors" are a heterogeneous group of lesions with dissimilar lineages of differentiation. Particularly in CERTs, it is likely that the rhabdoid phenotype represents a common end point of clonal evolution in tumors of clearly different origins. Despite these caveats, the authors do support retention of the diagnosis of "rhabdoid tumor," because the affiliated morphological pattern is uniformly attended by aggressive biological behavior despite potential dissimilarities at a subcellular level.

Abdominal Neoplasms↗

Interphase fluorescence in situ hybridization (FISH) as a powerful tool for the detection of aneuploidy in multiple myeloma.

Conventional cytogenetic (CC) studies performed in multiple myeloma (MM) are difficult because of the low proliferation rate of plasma cells (PC). The purpose of this study was to compare results obtained by CC and by FISH for the detection of numeric chromosomal changes in patients with MM. PC DNA content, CC and interphase FISH analysis were performed on 29 consecutive patients with MM. Fifteen patients (control group) had known Cytogenetic abnormalities identified by CC. The other 14 patients (study group) had a normal karyotype but an abnormal DNA content. Bone marrow material prepared for CC or cytospin slides were probed with classical satellite III or alpha satellite DNA sequences for chromosomes 3, 7, 8, 9, 11 and 15 (chromosomes 3, 7, 9, 11, 15 probes for hyperdiploid patients and the chromosome 8 probe for hypodiploid patients). In the control group, an unexplained discrepancy between CC and FISH occurred for only one chromosome in one patient. Also in this group, four patients had only one abnormal cell by CC and the numeric changes in these patients were always confirmed by FISH analysis. In the study group, FISH analysis showed an abnormal result in all but one patient. From these data, we conclude that FISH improves the detection of cytogenetic abnormalities in multiple myeloma. Using commercially available DNA probes for the most frequent numeric changes and slides for CC or cytospin slides, we demonstrated abnormal cytogenetics by FISH in 28/29 patients. In further studies, use of FISH could permit a more accurate description of numeric changes and their prognostic value in MM as well as an approach to clonal evolution. It would also be of interest in the study of monoclonal gammopathies of undetermined significance.

Adult↗

Incidence of chromosome numerical changes in multiple myeloma: fluorescence in situ hybridization analysis using 15 chromosome-specific probes.

The presence of complex karotypes with frequent numerical and structural abnormalities has been reported in 20 to 50% of multiple myeloma (MM) patients. This variability is mainly due to the difficulty of conventional cytogenetics to obtain tumor metaphases representative of all possible neoplastic clones in MM. To gain insight into the real incidence of numerical chromosome changes in MM we have studied by fluorescence in situ hybridization technique 15 different human chromosomes, 1, 3, 6, 7, 8, 9, 10, 11, 12, 13, 15, 17, 18, X, and Y, in a series of 52 MM patients. In all cases, the DNA index assessed by a propidium iodide/CD38 double-staining technique with flow cytometry was simultaneously investigated for correlation, with fluorescence in situ hybridization results. Additional aims of this study were 1) to analyze whether the abnormalities detected were common to all plasma cells or were present in only a subpopulation of tumor cells, 2) to explore changes caused by disease progression, and 3) to establish possible associations among the altered chromosomes. Although the overall incidence of numerical abnormalities was 67%, this frequency increased to 80% in the 41 cases in which 7 or more chromosomes were analyzed. Trisomies were significantly more common than monosomies (84% versus 16%). Chromosomes 9 and 15 were the most frequently altered (52% and 48% of cases, respectively), with all of their abnormalities corresponding to trisomies. The most frequent losses involved chromosomes 13 (26%) and X in females (32%). Other common numerical changes corresponded to chromosomes 1 (39%), 11 (37%), 6 (32%), 3 (31%), 18 (29%), 7 (28%), and 17 (22%). By contrast, chromosomes 8(13%), 10(8%), and 12(3%) were rarely altered. DNA aneuploidy by flow cytometry was detected in 67% of patients, and a high degree of correlation was observed between the DNA index obtained by flow cytometry and the chromosome index derived from fluorescence in situ hybridization studies, calculated according to two mathematical formulas (coefficient of correlation of 0.82 and 0.91 when at least 7 or 12 chromosomes were considered, respectively). The frequency of numeric chromosome aberrations was higher in those patients with progressive disease and, interestingly, trisomy of chromosome 8 was exclusively detected in this latter group of patients. Our study shows that, with the exception of chromosome 8, a possible marker of clonal evolution, the numeric chromosome changes are present in nearly all malignant plasma cells (r > 0.84). Finally, frequent associations between chromosomal aberrations were observed (ie, chromosomes 6, 7, 9, and 17; 7 and 15; and 11 and 17). By excluding them, it was found that two triple combinations of chromosome-specific probes, chromosomes 1 and 9 together with either chromosome 13 or 15, could be a useful marker for detection of residual disease, as it permits the identification of most MM patients displaying numerical changes.

Aged↗