[Complete cytogenetic response to interferon-alpha in a patient with chronic myelogenous leukemia undergoing hemodialysis].

We describe a complete cytogenetic response to interferon-alpha in a patient with chronic myelogenous leukemia undergoing chronic hemodialysis. Although IFN-alpha therapy has been applied to patients with chronic hepatitis C receiving hemodialysis, the pharmacokinetics of IFN-alpha in patients with poor renal function still remain unclear. In the present patient, the serum IFN-alpha concentration remained high even 48 hours after injection (42.9 IU/ml), and IFN-alpha was almost completely removed by hemodialysis (< 6 UI/ml). The patient was treated with IFN-alpha (3 x 10(6) IU, three times a week), and cytogenetic disappearance (0%) of the Ph-positive clone was confirmed 31 months after the start of therapy. Recombinant human erythropoietin (Epo) was used to treat anemia due to renal failure and IFN-alpha therapy. The anemia was controllable with Epo, and no adverse effect was observed.

Rearrangement of the BCL6 gene in B-cell lymphoid neoplasms: comparison with lymphomas associated with BCL2 rearrangement.

We report a series of B-cell neoplasms with regard to rearrangement of the BCL6 gene on chromosome band 3q27. Southern blot analysis using probes from the major translocation cluster (MTC) region of the BCL6 revealed rearrangement in 21/197 patients (10.7%) with B-cell neoplasms studied at presentation, and 11/25 patients (44%) first studied at relapse. In non-Hodgkin's lymphoma (NHL) studied at diagnosis, rearrangements of the BCL6 gene were not closely associated with a specific histopathologic subtype but distributed in subcategories in the Working Formulation. The incidence in follicular lymphoma was 12.1%, with significantly higher frequency in mixed and large cell subtypes, and that in diffuse aggressive lymphoma was 14.1%. Comigration analysis using probes from the immunoglobulin genes revealed association of the BCL6 gene with one of the three immunoglobulin loci in 9/25 cases analysed. A comparative study between NHL associated either with BCL2 or BCL6 rearrangement showed that advanced disease and bone marrow involvement were more frequent in BCL2(+) NHL. In contrast, extranodal involvement was more frequently observed in the BCL6(+) NHL. The survival curve of BCL6(+) NHL was characterized by a rapid decline followed by a plateau. Of the total of 32 BCL6(+) patients, six carried both BCL2 and BCL6 rearrangements; five of these six showed clinicopathological properties characteristic of follicular lymphoma, suggesting that the presence of the two genetic abnormalities does not necessarily have synergistic effects on malignant phenotypes. The high level of BCL6 expression in follicular lymphoma cell lines carrying a BCL2 rearrangement suggests that the deregulated BCL2 gene may have an effect on the development of genetic abnormalities of the BCL6 gene. The present study suggests that BCL6 gene rearrangement is primarily involved in large cell lymphoma irrespective of growth pattern of neoplastic cells, and that BCL6(+)BCL2(-) NHL could be curable with modern intensive chemotherapy.

Involvement of the BCL3 gene in two patients with chronic lymphocytic leukemia.

The t(14;19)(q32;q13) is a recurring translocation found in some patients with chronic lymphocytic leukemia (CLL), and the t(14;19) juxtaposes the BCL3 gene on chromosome 19 with the immunoglobulin heavy chain gene (IGH) locus on chromosome 14. Genomic DNAs from 49 patients with chronic B-cell leukemia and the related lymphomas were examined by Southern blot hybridization using 2 separate probes, named p alpha 1.4P and p alpha .5B, from the BCL3 gene locus. None of the 18 patients with leukemic manifestations of non-Hodgkin's lymphomas had detectable BCL3 rearrangements. Of 31 patients with CLL, 2 had the BCL3 rearrangements. A comigration study using the C alpha and C epsilon constant gene probe from IGH indicated that the t(14;19) translocation occurred in these 2 patients, and they were diagnosed with CLL/prolymphocytic (PL) according to the French-American-British (FAB) classification. Probes for the IGH locus revealed that leukemia cells of the 2 patients each were clonal, indicating that both small lymphocytes and prolymphocytoid cells found in the peripheral blood of one patient had the t(14;19), as well as a major population of the small lymphocytes in the peripheral blood of a second patient. It thus appears that tumor cells carrying the t(14;19) constitute a distinct disease entity in a group of chronic B-cell leukemia, that has a converting potential to more aggressive forms.

[Clinical and cytological features of acute myelogenous leukemia with 8; 21 chromosome translocation].

Eight cases of acute myelogenous leukemia with (8; 21) translocation were reported. As recently reported, they showed following features: M2 morphology in FAB classification (all 8 patients), abnormal granulocyte maturation, i.e. large granules and pseudo Pelger-Huet forms (5), Auer rods (8), occasional eosinophilia (2), frequent loss of one sex chromosome (5), the low neutrophil alkaline phosphatase activity (5), and tumor formation (one). Both CD13 and CD33 antigens were expressed on smaller number of leukemic cells than the other AML (M2) cells, whereas CD34 and HLA-DR antigens were expressed on higher number of cells. Interestingly CD19 antigen was detected on a small to large population of tumor cells from four out of six patients. Despite the high remission rate, many of them relapsed within one year. More intensive postinduction and maintenance therapy should be considered for those patients.

A novel translocation, t(2;5)(p23;q35), in childhood phagocytic large T-cell lymphoma mimicking malignant histiocytosis.

We report a novel chromosome translocation--t(2;5)(p23;q35) or its variant, t(2;5;13)(p23;q35;q12)--in 3 patients with peripheral T-cell lymphoma. All 3 were female children who had peripheral lymphadenopathy without organomegaly and underwent complete remission with or without chemotherapy. Their tumors were characterized histologically by predominant large cells, at times showing phagocytosis, and immunologically by peripheral T-cell phenotype and expression of Ki-1 antigen and epithelial membrane antigen (EMA). Since the same translocation has been reported in the literature in 4 patients with malignant histiocytosis (MH), and our patients had histologic features suggestive of that disease, it is likely that many tumors previously interpreted as MH are actually phagocytic large T-cell lymphoma carrying this translocation.

Involvement of bcl-2 gene in Japanese follicular lymphoma.

A t(14;18) (q32;q21) chromosome translocation is closely associated with the follicular lymphoma, which is prevalent in the United States, and the t(14;18) causes the juxtaposition of a bcl-2 gene on chromosome 18 with an immunoglobulin heavy-chain gene locus on chromosome 14. Genomic DNAs from 30 Japanese patients with follicular lymphoma were examined for the molecular features by Southern blot hybridization. Using probe b for the major breakpoint cluster region of a bcl-2 gene, the rearrangements were detected in eight patients. Six of the eight patients had breakpoints located within the major breakpoint region, while two had breakpoints outside this cluster region but within the region of the 7.5-kb SstI fragment containing the probe b sequence. In two patients, pFL-2 probe detected the bcl-2 gene rearrangements that occurred near or within the minor breakpoint cluster region. These ten patients had a rearranged JH-containing fragment that migrated with the rearranged bcl-2 fragment. In the other 20 patients, these two chromosome 18-specific DNA probes did not detect the bcl-2 rearrangements. Compared with studies performed in the United States, the statistical analysis indicates a significant difference in frequency of the bcl-2 gene rearrangements near or within the major breakpoint cluster region (P = 0.0027) and the minor breakpoint cluster region (P = 0.029). However, the distribution difference of these events was not significant.

Significance of extra 18q- chromosome in Japanese t(14;18)-positive lymphoma.

Karyotype evolution of t(14;18)-positive lymphoma was studied in 13 Japanese patients. The extra 18q- chromosome, found in six of ten patients with complex karyotypes, was the most common change subsequent to a t(14;18)(q32;q21) chromosome translocation. The additional change was interpreted as being a duplication of an 18q- derived from a t(14;18). The six patients had transformed histology of follicular small cleaved cell lymphoma or diffuse large cell lymphoma, and five of them had extranodal expansion associated with a poor prognosis. These findings indicate that the extra 18q-, together with other chromosome abnormalities, is closely associated with the advanced grade disease of t(14;18)-positive lymphoma, and the extra chromosome is evolutionally comparable with the second Philadelphia (Ph1) chromosome often found in the blastic phase of chronic myelocytic leukemia carrying a t(9;22)(q34;q11). In addition, since the extra 18q- is rarely found in American patients with t(14;18)-positive lymphoma, there appears to be a difference in the karyotype evolution between Japanese and American patients.

[Autosomal translocation and associated male infertility].

Four balanced autosomal reciprocal translocations were found through mitotic chromosome analysis among 72 subfertile males, 27 with azoospermia and 45 with sperm counts below 40 X 10(6)/ml. They were 46, XY, t(3; 20; 21) with azoospermia, 46, XY, t(14; 21) with sperm counts below 1 X 10(6)/ml, 46, XY, t(1; 19) lqh+ with azoospermia and 46, XY, t(3; 16) with sperm counts 27 X 10(6)/ml. Histological, cytogenetic and hormonal analysis were performed. Testicular biopsies from the first 3 carriers revealed complete spermatogenic arrest at the spermatocyte stage and meiotic studies of the same biopsies showed severe reduction in numbers of cells in 2nd meiotic division. In spite of severely defective spermatogenesis, serum gonadotropins of the carriers were within normal range, except for LH of the 4th case. Other chromosomal aberrations observed were 5 Klinefelter's syndrome, 2 autosomal minor variants (46, XY, 15p+ and 46, XY, 14s+) and 1 small Y.