Chronic T-cell leukemias. II. Cytogenetic studies

Deletion 6q as a recurrent chromosomal aberration in T-cell large granular lymphocyte leukemia

T-cell large granular lymphocyte (T-LGL) leukemia is an uncommon disease, with limited information on karyotypic aberrations. No consistent chromosomal changes have thus far been described. We report two cases of T-LGL leukemia who presented with severe anemia. The LGL were CD3+, CD4-, CD8+, CD56-, and CD161-, with variable expression of CD94, CD158a, and CD158b, and had clonal T-cell receptor gene rearrangement. A deletion of the long arm of chromosome 6 was the sole aberration in both cases. This is the first report of a recurrent chromosomal aberration in T-LGL leukemia.

Chromosomal abnormalities in T-cell large granular lymphocyte leukaemia: report of two cases and review of the literature

Cytogenetic information on T-cell large granular lymphocyte leukaemia (T-LGL; large granular lymphocytosis) is limited. We report two cases of T-LGL with unusual karyotypic aberrations. The first case showed a novel inv(7)(p15q22) as the sole chromosomal abnormality, while the second case showed an inv(14)(q11q32) with evidence of clonal evolution. The breakpoints 7p14-p15 and 14q11 coincide with the T-cell receptor (TCR)-gamma and TCR-alpha/TCR-delta gene loci respectively. This is the first report describing the possible involvement of T-cell receptor genes in karyotypic aberrations in T-LGL.

Biallelic mutations in the ATM gene in T-prolymphocytic leukemia

Ataxia-telangiectasia (AT) is an autosomal recessive disorder characterized by cerebellar ataxia, oculocutaneous telangiectasia, immune deficiency, genome instability and predisposition to malignancies, particularly T-cell neoplasms. The responsible gene, designated ataxia-telangiectasia mutated (ATM), was recently identified by positional cloning in the chromosomal region 11q22.3-23.1 (ref. 4, 5) ATM is 150 kb in length, consists of 66 exons and encodes a nuclear phosphoprotein of approximately 350 kDa (ref. 4-9). Although ATM is considered to be a tumorigenic factor in several human cancers, it has not yet been found mutated in tumors of non-AT patients. Given the marked predisposition of AT patients to develop neoplasms of the T-cell lineage, we analyzed a series of T-cell leukemias (T-prolymphocytic leukemia, or T-PLL) in non-AT patients in search of genomic changes associated with the development of this disease. Among the recurrent aberrations identified, deletion of the chromosome arm 11q was very frequent. Subsequent molecular cytogenetic analyses allowed us to define a small commonly deleted segment at 11q22.3-23.1 in 15 of 24 T-PLLs studied. Since this critical region contained ATM, we further analyzed the remaining copy of the gene in six cases showing deletions affecting one ATM allele. In all six cases, mutations of the second ATM allele were identified, leading to the absence, premature truncation or alteration of the ATM gene product. Thus, our study demonstrates disruption of both ATM alleles by deletion or point mutation in T-PLL, suggesting that ATM functions as a tumor-suppressor gene in tumors of non-AT individuals.

Trisomy 8q due to i(8q) or der(8) t(8;8) is a frequent lesion in T-prolymphocytic leukaemia: four new cases and a review of the literature

Cytogenetic abnormalities found in four cases of T-cell prolymphocytic leukaemia (T-PLL) are described. An isochromosome 8q was found in three patients and a t(8;8) in one. In the four cases, karyotypes were complex and showed a high degree of instability. In addition, we reviewed 27 published cases of cytogenetically studied T-PLL. On the whole, the most frequently recurring anomalies in T-PLL are 14q lesions with nonrandom breakpoints, inversion (14)(q11q32) or tandem translocations (14;14) (not seen in any of our cases) and trisomy for 8q. mainly due to i(8q), found in more than 40% of patients each. Similar structural anomalies were found almost as frequently among the 23 cytogenetically studied cases of so-called T-chronic lymphocytic leukaemia (T-CLL) reported prior to 1989. It is now accepted that the T-cell counterpart of B-CLL either does not exist or is exceedingly rare and thus previously reported cases of T-CLL sharing the chromosomal characteristics of T-PLL may well have been misdiagnosed examples of T-PLL. Isochromosomes 8q are exceptionally found in other types of haematological malignancies. However, i(8q) could not be shown to be the primary lesion in any case in T-PLL and the role of trisomy for 8q, as well of the associated monosomy 8p, is entirely unknown.

Cytogenetics in CLL and related disorders

Chromosome analysis of more than 1200 patients with chronic lymphocytic leukaemia reported to the International Working Party on Chromosomes in CLL and in the literature is analysed. Clonal chromosomal abnormalities are found in about half of the patients, and one third of those with clonal aberrations have trisomy 12, with or without additional changes. The most common structural abnormalities involve the long arm of chromosome 13, usually as deletions involving 13q14, the site of the retinoblastoma gene. Other recurrent abnormalities are deletions of the long arms of chromosome 11 and 6. 14q+ markers are frequent in patients at advanced stage, but are almost always within complex abnormalities. The number of clonal abnormalities in the CLL cells has a strong prognostic impact. Trisomy 12 as a single abnormality is an adverse prognostic sign, whereas patients with 13q abnormalities generally do comparatively well. Lymphoid leukaemia with monoclonal immunoglobulin secretion frequently involves clonal chromosomal abnormalities, and the type of change is similar to that seen in true CLL. In B cell prolymphocytic leukaemia, t(11;14) is a common finding, together with trisomy 12. T cell prolymphocytic leukaemia is characterized by an inversion of the long arm of chromosome 14, with breaks at q11 and q32, and trisomy of 8q, whereas large granular lymphocytic leukaemia has shown no consistent abnormality. Hairy cell leukaemia seems to involve a specific set of non-random chromosome abnormalities, such as inv(5)9.

Inversion (4)(p13q28) in two cases of acute nonlymphocytic leukemia

An identical inversion, inv(4)(p13q28), was found to occur as the sole karyotypic anomaly in two patients with acute nonlymphocytic leukemia. The breakpoints are different from any previously described structural rearrangements of chromosome 4.

T-cell prolymphocytic leukemia with an unusual phenotype CD4+ CD8+

A patient with T-cell prolymphocytic leukemia (T-PLL) is described. The outcome was poor, with death 8 months after diagnosis, despite several therapeutic interventions. The cells carried both CD4 and CD8 epitopes, but other thymocytic markers were absent. The spleen showed infiltration of CD4+ CD8+ prolymphocytes in the red pulp and in T-cell-dependent areas of the white pulp. Immunologic function studies revealed proliferation after stimulation with mitogens and even several antigens. However, in the mixed lymphocyte culture the T-PLL cells did not proliferate. Cytotoxic T-cells could not be induced. In T-non-T recombination experiments neither helper nor suppressor cell function was found for pokeweed mitogen-dependent plasmablast generation of normal B-cells. Cytogenetically, many abnormalities were found. Among them, 14q+; absence of chromosomes 8, 11, and 22; and the presence of large marker chromosomes and fragments.

Clonal evolution of T-cell chronic lymphocytic leukaemia in a patient with ataxia telangiectasia

Ataxia telangiectasia (A-T) is an autosomal recessive disorder in which patients show an unusual predisposition to malignant disease, including T-cell chronic lymphocytic leukaemia. We report here the steady growth over 5 years of a complex, cytogenetically abnormal clone of T lymphocytes in an A-T patient who was subsequently found to have an OKT3/OKT8 chronic lymphocytic leukaemia. The tumour cells at diagnosis had clearly evolved from a pre-existing, cytogenetically abnormal T-cell clone which contained an inv(14) chromosomal inversion alone.

Application of cytogenetics in neoplastic diseases

This review will concern itself with the application of cytogenetic findings in neoplastic diseases. This application can be divided into two general categories: practical and theoretical. The practical applications reside in utilizing karyotypic changes, particularly in leukemias and lymphomas, not only for diagnostic purposes but also for predicting response to therapy and prognosis. This is especially evident in the various acute nonlymphocytic leukemias and in most of the acute lymphoblastic leukemias. Thus, a definite correlation exists between the cytogenetic findings and the various clinical, laboratory, and cytologic parameters of most of the leukemias. Undoubtedly, these leukemias will ultimately be classified and defined more in terms of their cytogenetic aspects than any other. Though the application in lymphoma is not at the same level as that in leukemia, developments in that field certainly indicate a similar utilization of the cytogenetic findings in these diseases. The presence or absence of a Ph1 chromosome in a chronic myelocytic leukemia has been utilized widely, not only in the diagnosis but also in the predictability of response; the cytogenetic findings have also been utilized in predicting the blastic phase of disease. The list of specific chromosome changes in various solid tumors is of a lesser number, but significant developments indicate that the applicability of chromosome changes in these diseases will, also, be established in the near future. The application of chromosome findings to theoretical aspects of malignancy has assumed an important place recently in the demonstration that so-called oncogenes (or proto-oncogenes) are located or associated with areas of human chromosomes in which breaks and translocations are involved. Thus, it appears that chromosome changes in human malignancy, once their specificity is established, are important parameters in the clinical and theoretical aspects of the disease. A discussion will also be given on primary vs. secondary chromosome changes and their significance in the biology and behavior of the malignancy.

Functional and multimarker analysis of T-cell chronic lymphocytic leukaemia

The morphology, immunophenotype, cytoenzymatic and functional activities of T lymphocytes from 4 patients with chronic lymphoproliferative disease of T-cell origin were studied. Clonal proliferation was demonstrated by distinctive chromosomal abnormalities involving chromosomes 2 and 14. Patients 1 and 2 were classifiable as OKT4+ T-cell chronic lymphocytic leukaemia (T-CLL) and patient 3 as OKT4+/OKT8+ T-CLL, with helper function in vitro only in patient 1. Patient 4 has low-grade lymphocytosis with benign clinical course, with cells showing morphology of large granular lymphocytes (LGL), and immunophenotype HNK-1+, ER+, Fc gamma receptor+, OKT3+, OKT11+ and OKT8+, as well as natural killer activity, radiosensitive suppressor activity on Ig secretion and responsiveness to PHA; this case was interpreted as LGL leukaemia. This study indicates that a large proportion of cases of true T-CLL may belong to the OKT4 subset, and that extensive investigations should be made of the lymphocytic OKT8+/T gamma forms to characterize them precisely.

Chronic T cell lymphocytosis: a review of 21 cases

Twenty-one patients are described with a proliferation of morphologically mature T lymphocytes. The clinical course was chronic in most, and splenic enlargement the main clinical finding; skin involvement and lymphadenopathy were rare. The mean lymphocyte count at presentation was 8 X 10(9)/1 (range 0.75-24 X 10(9)/1). Nineteen of these patients showed some form of cytopenia (18 neutropenia, two red cell aplasia, eight thrombocytopenia) and one had hypogammaglobulinaemia. Seven patients had long-standing arthropathy serologically proven to be rheumatoid arthritis and these had previously been considered to have Felty's syndrome. Five of the group have died (three with an aggressive course), but most have remained stable for prolonged periods with a slow increase in peripheral lymphocyte count and marrow infiltration. Spontaneous regression was never observed but in two patients a prolonged remission was achieved by chemotherapy. The lymphocytes were morphologically and phenotypically homogeneous at presentation and remained so post-splenectomy; they contained azurophilic granules, stained with acid phosphatase but weakly or not at all with alpha napthyl acetate esterase. Membrane phenotyping shows the majority of the cells to be E+, Fc gamma+, OKT3+, OKT8+. Most cells do not stain with OKT1-like reagents and a significant number express HLA-Dr. From these and other reported cases it is clear that this condition represents a distinct entity resulting from the expansion of a subset of cytotoxic/suppressor T cells--the question of the benign or neoplastic nature of the disease remains open. Using T cell-specific antisera and E-rosetting techniques, a small percentage of CLL cases have been shown to be of T-cell origin (TCLL) (Dickler et al, 1973; Lille et al, 1973). Estimates of the percentage vary but in most series T-CLL has been diagnosed in less than 5% (Brouet & Seligmann, 1981), and this is supported by date from the M.R.C. Leukaemia Unit which found T-CLL in only 1.5% of 600 cases of CLL examined by marker studies (D. Catovsky, unpublished). Amongst the published reports of T-CLL a variety of clinical and morphological entities have been described including T prolymphocytic leukaemia (TPLL) (Brouet et al. 1975) and adult T cell disease in Japanese (Uchiyama et al, 1977) and West Indian Caribbean groups (ATLL) (Catovsky et al, 1982). In the original series of Brouet & Seligmann (1981) the group was defined as presenting in middle age with marked hepatosplenomegaly, some lymphadenopathy, skin involvement and with an aggressive disease course; peripheral blood and marrow lymphocytosis were variable.(ABSTRACT TRUNCATED AT 400 WORDS)

Chromosome studies in patients with T-CLL chronic lymphocytic leukemia and expansions of granular lymphocytes

Chromosome analyses were carried out in eight patients with lymphoproliferative disorders of mature T and NK cells. Three cases were characterized by an abnormal expansion of granular lymphocytes (GL), one by a lymphoma of GL with leukemic spread, and four by an OKT4-T-CLL. In four patients cytogenetic studies were performed on bone marrow cells; in seven patients peripheral blood lymphocytes were examined by either direct preparations or PHA-stimulated cultures. Six patients displayed a normal karyotype. Two cases belonging to the OKT4-T-CLL group had a chromosome number ranging from 44 to 47, with multiple numerical and structural clonal anomalies. Clonal anomalies could be a feature of patients with the more aggressive clinical course.

Adult T-cell lymphoma/leukemia in a Caribbean patient: cytogenetic, immunologic, and ultrastructural findings

Cytogenetic findings on immunologically and morphologically characterized leukemic cells from a Caribbean patient with adult T-cell lymphoma/leukemia (ATLL) (HTLV+) are reported. Marker studies on peripheral blood lymphoid cells showed a mature postthymic phenotype: TdT-, OKT3+, OKT4+, OKT6-, OKT8-, 3A1-, anti-HLA-DR-. Light and electron microscopic analysis revealed a great cellular pleomorphism with respect to nuclear features. Three main types of leukemic cell were observed: typical multilobed ATLL lymphocytes, Sézary's syndrome (SS) cells, and cells intermediate between those two. Chromosome studies on PHA-stimulated cultures revealed three clones. The predominant clone was hyperdiploid; significant abnormalities were 1q+, 14q+, and 6q- (breakpoint q21), which are known to occur in lymphoid malignancies, together with trisomy 7q and i(17q), which have been reported previously in Japanese ATLL and the small variant of SS, respectively. The 14q+ marker was t(11;14)(q13;q22-24). The incidence of 6q-, trisomy 7q, and i(17q) varied within the main clone, and it is speculated that these chromosome abnormalities might be related to the variation observed in the cell types of this patient. Two minor clones had 6q- (breakpoint q25) and 13q+ markers, respectively. It was not possible to unequivocally establish the relationship between these three clones. The chromosomal, morphologic, and immunologic findings in this case support a close relationship between ATLL in Japan and in the Caribbean basin, as well as between the proliferating cells of ATLL and SS.

Cytogenetic studies in a case of T-cell prolymphocytic leukemia

The authors describe cytogenetic aberrations observed in a case of T prolymphocytic leukemia. C11 deletion (q14) B5 deletion (pter), D14q +, E20 trisomy, and two markers are the main anomalies of the complement.

Membrane markers, karyotypic abnormalities, ultrastructure and functional properties of lymphocytes in a case of 'D-cell' chronic lymphatic leukemia

D cells are lymphocytes bearing both receptors for the third complement component and the ability to form spontaneous rosettes with SRBC. We report the case of a patient with a D-cell chronic lymphatic leukemia who presented a long evolution without treatment and whose leukemic cell characteristics have been extensively studied. Cytogenetic analysis showed numerous karyotypic abnormalities among leukemic cells; all metaphases were hypodiploid and arranged in four different clones; seven marker chromosomes were present. The cells were found to bear human T-cell specific antigen, the T helper/inducer phenotype, HLA-A and HLA-B determinants, but no HLA-DR antigens. They displayed a high proliferative response to PHA and Con A, no response to PWM stimulation, and possibly the capacity of allogeneic stimulation in the mixed lymphocyte culture system. Assays for cell-mediated cytotoxicity in the CML system, and for K and NK activities were negative.

Chromosome abnormalities in B-cell prolymphocytic leukemia: a study of nine cases

Chromosome abnormalities were demonstrated in 50-100% of Giemsa-banded metaphases from nine cases of B-cell prolymphocytic leukemia (B-PLL). Mitoses were obtained with pokeweed mitogen following pretreatment of peripheral blood (PB) prolymphocytes with neuraminidase-galactose oxidase. Chromosome 14 was abnormal in eight of the nine cases: a marker 14q+, with breakpoint at band q32 in seven and trisomy 14 in one. In four cases the abnormal No. 14 was one of several primary abnormalities and in four others it was seen in secondary clones. The origin of the translocated material was unknown in three cases, in two it resulted from t(11;14), later becoming t(11;14;21) in one of them, t(1;14) in another, progressing later to t(1;14;17); in yet another patient, the 14q+ was the result of a complex rearrangement t(6;14;17). Abnormalities of chromosome 6 were seen in six cases: 6q- as the primary abnormality in three; trisomy 6 was part of secondary changes in one case. Structural abnormalities of chromosome 1 were seen in six cases: 1q- in four (in one as the only abnormality), 1q+ in one case, and 1p- in another, both in the main clone. Trisomy 12 was demonstrated in three cases but not as the primary change. Spleen cells in two patients showed a higher frequency of abnormalities than in the PB, supporting the concept of the spleen being the organ primarily involved in B-PLL. Evidence of karyotypic evolution was demonstrated in six patients, in some clearly associated with clinical progression of the disease. The type and frequency of the abnormalities observed in B-PLL resemble those seen in non-Hodgkin's lymphomas and suggest major differences from B-CLL, although a relationship with the latter can not be completely ruled out at present.

A case of erythroleukaemia with homogeneously staining regions on chromosomes

A case of erythroleukaemia with homogeneously staining regions on chromosomes is described. The number of chromosomes in bone marrow cells varied from 41 to 46 with a mode of 43. A variety of structural and numerical chromosomal abnormalities was observed. Two marker chromosomes with homogeneously staining regions were found in all aneuploid cells examined. Intensive chemotherapy failed to induce a remission and the patient died 3.9 months after diagnosis. The relation of the homogeneously staining regions on chromosomes to the two courses of chemotherapy prior to cytogenetic study is discussed.