Frequency of BCR-ABL fusion transcripts in Serbian patients with chronic myeloid leukemia.

PURPOSE: The aim of this study was to analyze the occurrence of the most frequent BCR-ABL transcript variants (b3a2, b2a2 and e1a2) in Serbian patients with chronic myeloid leukemia (CML) and compare it with the occurrence reported in other populations. METHODS: We analyzed peripheral blood and bone marrow samples of 136 Serbian patients with CML by RT-PCR and cytogenetic methods. RESULTS: In 100 patients (73.5%) the b3a2 and in 34 (25%) the b2a2 forms of BCR-ABL were detected. One (0.75%) patient was BCR-ABL negative, but in lymphoblastic transformation he expressed the e1a2 [corrected] transcript of BCR-ABL. One (0.75%) patient displayed both b2a2 and b3a2 forms of BCR-ABL. Analysis of this group according to karyotype showed b3a2 predominance (79%) in patients with classic t(9;22); b2a2 was found in 20% and both b2a2 and b3a2 forms in 1%. In variant translocations b3a2 in 65% and b2a2 in 35% of the patients were detected. In contrast, the subgroup with normal karyotype expressed slight predominance of the b2a2 form (50%); b3a2 was found in 43% of the patients and one patient (7%) displayed e1a2. CONCLUSION: Predominance of the b3a2 form in Serbian patients with CML is in concordance with other relevant investigations, conducted mostly on Caucasian ethnic groups, but in contrast to the study performed on the Mestizo ethnic group in Ecuador. Slight predominance of the b2a2 form was also noticed among the patients with normal karyotype.

Detection of t(14;18), P53 and RAS gene mutations and quantification of residual disease in patients with B-cell non-Hodgkin's lymphoma.

UNLABELLED: PCR analysis has been demonstrated as a valuable tool for detection of minimal residual disease (MRD) in lymphoid malignancies. However, the finding that patients with evidence of MRD sometimes remain in long-lasting remission directs further investigations toward biology of residual disease and/or quantification of MRD level. The study included 40 B-NHL patients--13/40 patients with high- (HG) and 27/40 with low-grade (LG) lymphoma. Seven patients achieved partial clinical remission (PR) and 33 patients achieved complete clinical remission (CCR) after chemotherapy. Peripheral blood samples were analyzed for MRD at up to ten follow-up points while samples of MRD+ patients and patients who achieved partial clinical response after therapy were further analyzed for the presence of t(14;18) and P53 and RAS genes mutations. The level of MRD was quantified in eight patients by PCR-limiting dilution method. RESULTS: MRD was found in 13/33 patients (12 LG and 1 HG) who achieved CCR. The incidence of relapse was significantly higher in MRD+ vs. MRD- B-NHL patients (Fisher's exact test, p = 0.0083). In the LG group the incidence of relapse between MRD+ and MRD-patients was not significantly different. In the HG group MRD was detected in only one patient who subsequently relapsed. Significant difference in DFI between MRD+ and MRD- patients was not observed. Concerning MRD+ patients in CCR and patients who achieved PR, t(14;18) was found in six patients (4 relapsed). In the same group of patients P53, K- and N-RAS mutations were not found. H-RAS mutations were found in six patients--3 relapsed and 3 remain in CCR. The calculated number of IGH copies ranged from 4800 to 44,000. Our results demonstrated positive correlation between MRD-positivity and incidence of relapse in B-NHL patients, but could not indicate significance of P53 and RAS mutations for evaluation of residual clone malignancy. The study implies that MRD level, measured at one follow-up point, does not correlate with clinical outcome. The measurement of MRD level sequentially, at different follow-up points, seems to be a better parameter for the prediction of disease course.

Distinct spectrum of N-ras mutations in aml and mds patients in yugoslavia.

Mutations that activate ras genes were demonstrated to be associated with certain types of malignancies. Multiple point mutations were predominantly found in the N-ras and occasionally in the K-ras genes. The analysis of 4 MDS, 23 AML and 11 CML patients from Yugoslavia revealed the prevalence of the N-ras mutation (83%) over K-ras mutations (17%). Although the frequencies of the N- and K-ras mutations in these patients were similar to the ones reported for patients from USA and Japan, the N-ras mutational spectra considerably differed. The prevailing type of mutation in patients from Yugoslavia was G-to-T transversion at the first position in the codon 12 of the N-ras gene. This study supports a hypothesis that different geographical and environmental factors may cause the accumulation of different type of point mutations in the same target gene.

[Antilymphocyte globulin in the treatment of aplastic anemia]. / Antilimfocitni globulin u lecenju aplasticnih anemija.

Between January 1986 and July 1990, 17 patients with acquired aplastic anemia were treated with ALG or ATG combined with high doses of methylprednisolone. The mean age was 24.3 years (from 4 to 51 years). There were 9 cases with idiopathic etiology of acquired aplastic anemia; in 7 cases aplastic anemia was developed during or after HBsAg infection. In one case aplastic anemia was developed during tuberculous kidney infection. The remission of the disease was achieved in 11 of 17 cases (complete remission in 9-53%, and partial in 2-12% patients). Six (35%) patients did not respond to the treatment with ALG. One patient died of infection and hemorrhagic complications, two weeks after the therapy, without responding to the treatment with ALG. The four year survival rate without recidives was 65% (11/17). Four (23.5%) patients developed clonal diseases: PNH in 2; MDS in 1 and AL in 1 patient, 24, 38, 9 and 6 months after the therapy with ALG, respectively. The age of the patients is a valuable prognostic parameter (all patients under 20 years of age entered the remission), which cannot be said for pretreatment levels of reticulocytes, neutrophils and platelets. In none of the patients adverse effects of ALG were observed. The treatment was conducted in isolated rooms with sterile air circulation. ALG combined with high doses of methylprednisolone, for the majority of patients with aplastic anemia represents a drug of choice and is an appropriate alternative therapy to alogenic bone marrow transplantation, especially for patients with no HLA identical bone marrow donor.

[Erythrocyte cell aplasia in chronic myeloid leukemia--coincidence or pathogenic link]. / Aplazija eritrocitne loze kod hronicne mijeloidne leukemije--koincidencija ili patogenetska povezanost.

At the Clinic for Hematology of the Military Medical Academy in Belgrade two patients had been treated from November, 1983 to July, 1986, in whom the existence of chronic myelogenous leukemia (CML) was established with negative Ph'-chromosome, as well as the existence of acquired partial erythrocyte aplasia (APEA). In the male patient of 58 years of age and the female patient of 71, APEA was established at the same time as CML. The maladies showed to be refractory to antileukemia (busulfan, hydroxyurea) and immunosuppressive (corticosteroid, androgen) therapy in both of the patients, while in the first patient splenectomy was also without effect on the course of the disease. Serumal inhibitors of erythropoiesis were not registered. After 18 months of disease duration one patient had a blastic transformation of CML into acute myeloblastic leukemia (AML) of the M1 form, and death appeared under the clinical manifestation of sepsis during iatrogenic aplasia of the bone marrow. The other patient died 32 months after start of illness because of intracranial hemorrhage, without signs of HML metamorphosis. In the discussion, previous illnesses are considered--kidney tuberculosis and polyarthralgias--as well as the applied treatment of these illnesses (antituberculotics and nonsteroid antirheumatics) as possible etiological factors in the appearance of APEA. The mutual link between APEA and CML, though exceptionally rare, is possible, and erythroblastopenia can precede or occur simultaneously with CML or during its treatment. APEA is usually the sign of CML terminal metamorphosis into acute leukemia, though it sometimes coexists with CML as an independent malady.