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D K Kalwinsky

Publications and source records attributed to D K Kalwinsky.

66 records · Page 4Linked to original sources

Cytogenetic features of acute nonlymphoblastic leukemia in 73 children and adolescents.

We examined the leukemia cells of 81 consecutively admitted children and adolescents with acute nonlymphoblastic leukemia (ANLL) to determine the frequency and specificity of chromosomal abnormalities. Karyotypes were obtained for 73 (90%) of the 81 children, and 36 (49%) were abnormal. The modal karyotypes for the cases were tightly clustered in the diploid range; only 5 (7%) were hypodiploid, with 45 chromosomes each, and only 2 (3%) had greater than 50 chromosomes. Specific chromosomal abnormalities in the abnormal karyotypes were compared to morphologic subgroups of ANLL. An 8;21 translocation was found in 6 of 9 cases with M2 morphology but was also found in 1 case with M1 morphology. One of 4 with M3 (progranulocytic) morphology had a 15;17 translocation, and another had a 17q deletion. A structural abnormality in 11q was found in 3 of 7 patients with M5 (monoblastic) morphology, 2 of whom had a 9;11 translocation. The only case of M6 had a 22q-or Philadelphia chromosome in addition to other abnormalities. Statistical analysis of 27 abnormal karyotypes showed preferential structural rearrangement of 8q and 21q. We conclude that, in children as well as adults, specific structural abnormalities are correlated with certain morphologic subgroups of ANLL. However, other chromosomal changes associated with prior mutagenic exposure of adult ANLL were uncommon in children, which may suggest a difference in pathogenesis.

Acute Disease↗

Effects of the epipodophyllotoxin VP-16-213 on cell cycle traverse, DNA synthesis, and DNA strand size in cultures of human leukemic lymphoblasts.

Serial studies of human leukemic lymphoblasts (CCRF-CEM line) cultured with 0.25 to 2.5 microM VP-16-213 for 0 to 6 hr indicated that the mechanism of cytotoxicity of this compound involves a primary effect on DNA. The most striking early change shown by flow cytometry in VP-16-213-treated cells was a delay in S-phase transit before arrest of cells in G2. Coinciding with this S-phase delay was a selective inhibition of thymidine incorporation into DNA as well as concentration-dependent scission of DNA strands. Using alkaline elution methods, we were able to detect DNA breakage at concentrations of VP-16-213 well below the level required to demonstrate kinetic effects or inhibition of DNA synthesis. These data suggest that DNA strand scission is the initial event in the sequence of kinetic and biosynthetic changes leading to growth inhibition and death of VP-16-213-treated cells. Inhibition of replicon initiation due to strand scission is a plausible explanation for the cytotoxic action of this podophyllotoxin derivative.

Cell Cycle↗

VM-26 with prednisone and vincristine for treatment of refractory acute lymphocytic leukemia.

Fifty-six children with refractory acute lymphocytic leukemia (ALL) were assessed for remission-induction responses to VM-26 (250 mg/m2 per week) in combination with prednisone (40 mg/m2 per day) and vincristine (1.5 mg/m2 per week). Each child had been treated intensively with steroids, vincristine, daunorubicin and L-asparaginase. In fact, all patients had failed to respond to previous reinduction therapy with prednisone-vincristine or had relapsed while receiving vincristine. Our intent in this study was to test whether or not addition of VM-26 to prednisone-vincristine would overcome clinical resistance to these established agents. Complete remissions were induced in 17 patients (0.30) over 4 to 6 weeks. Five of these children, all clinically unresponsive to prednisone-vincristine alone, had complete remissions that lasted longer than 1 year; two remain in remission for 2 1/2 years and both are now off therapy. Myelosuppression, the most serious treatment complication, was documented in 20 of 26 evaluable patients. The median time to recovery of normal marrow function was 15 days. These results demonstrate further the potential of VM-26 in combined-drug treatment of refractory ALL. Whether the effectiveness of this combination represents potentiation of prednisone and vincristine activity by VM-26 or some other, as yet unidentified interaction, remains to be determined.

Adolescent↗

Metastatic epidural tumors in children.

Spinal cord compression is a rare but serious complication of malignant diseases in children. Epidural cord compression was noted in 81 patients within the past 17 years at this center. The complication developed at different times during the course of the primary disease. For 29 of our patients, cord dysfunction was one of the initial signs of cancer--Ewing sarcoma, neuroblastoma, Hodgkin disease, and malignant lymphoma. By contrast, for most of the patients with osteosarcoma and rhabdomyosarcoma, it appeared later in their clinical course. The treatment outcome of patients who were paraplegia with complete loss of sensory function for greater than or equal to 48 hours was poor. Only four of 22 in this group became ambulatory. Ten patients with osteosarcoma did not undergo laminectomies because they all had multiple metastases and terminal disease. Paraplegia developed in all ten. There was no difference in ambulatory rates among other patients, with or without laminectomies.

Child↗

Cytokinetically based induction chemotherapy and splenectomy for childhood acute nonlymphocytic leukemia.

A four-drug regimen, based on cell kinetic principles, induced complete remissions in 68 of 95 children (72%) with acute nonlymphocytic leukemia (ANLL). Patients entered remission after 2-5 weekly cycles of vincristine-daunorubicin (day 1) followed by sequential cytosine arabinoside and 6-azauridine (days 4-7). With continuation therapy of monthly vincristine-doxorubicin-cyclophosphamide, weekly cytosine arabinoside, and daily 6-mercaptopurine, the median duration of complete remission was 10 mo and the median survival time 21 mo. Portal triaditis, evident in 11 of 23 patients with liver biopsies, was associated with long remissions. A larger spleen size (greater than 5 cm) and a higher myeloblast labeling index (greater than 10%) at diagnosis were clearly related to shorter durations of remission. Splenectomy within 1 mo of remission had no statistically significant effect on the frequency of relapse or length of remission. Patients without central nervous system (CNS) leukemia at diagnosis, all treated prophylactically with intrathecal methotrexate, had a low frequency of initial CNS relapse (3/56, 5%). The 2-yr disease-free survival rate is 29% (20 of 68 patients attaining complete remission). fifteen patients have completed 2.5 yr of therapy, and each remains in continuous complete remission, off treatment, for 1+ -36+ mo. This induction chemotherapy was as effective as more intensive regimens, with the advantage of less toxicity and shorter periods of hospitalization.

Acute Disease↗

Prognostic importance of chromosome number in 136 untreated children with acute lymphoblastic leukemia.

Leukemia cell karyotypes were determined at diagnosis for 136 of 159 consecutive patients with acute lymphoblastic leukemia (ALL) who were followed for up to 35 mo. Ninety patients (67%) had abnormal karyotypes. Five chromosome categories were designated, based on the distribution of modal numbers: hyperdiploid greater than 50 (n = 41), hyperdiploid 47-50 (n = 18), pseudodiploid (n = 28), normal (n = 46), and hypodiploid (n = 3). Treatment response was assessed for the categories in terms of time to failure (induction failure, first relapse, or death). Children in the hyperdiploid greater than 50 category had the best responses to treatment, with only 2 failures, and those in the pseudodiploid category had the poorest (p less than 0.001). The remaining 3 chromosome categories had intermediate responses and formed a third prognostic group. This same influence of chromosome number on time to failure was evident within the 2 clinical prognostic groups: high risk, signified by a leukocyte count greater than 100 X 10(9)/liter, meningeal leukemia, mediastinal mass, or the presence of blasts that formed rosettes with sheep erythrocytes at 37 degrees C, and standard risk, indicated by the absence of these features. The influence of chromosome number on time to failure was also the same within the historically favorable prognostic group that had common ALL. Results of a multivariate analysis indicated that chromosome number was the strongest single predictor of outcome (p less than 0.001) and was the only variable that added significant prognostic information to leukocyte count (p less than 0.001). The combination of chromosome number and leukocyte count should more clearly distinguish patients with ALL at low or high risk of relapse.

Asparaginase↗

Aneuploidy and percentage of S-phase cells determined by flow cytometry correlate with cell phenotype in childhood acute leukemia.

Cellular DNA content distributions of propidium-iodide-stained bone marrow blasts were determined by flow cytometry (FCM) for 225 untreated children with acute leukemia and were correlated with leukemia cell phenotype and karyotype. Aneuploidy of the primary malignant stem line was detected in 54 cases (24%): 51 hyperdiploid and 3 hypodiploid. A second stem line with approximately twice the DNA content of the primary stem line was recognized by FCM in 28 cases (23 ALL, 5 ANLL) and may be an important source of leukemia cell heterogeneity. The degree of DNA content abnormality detected by FCM was highly correlated (r = 0.98) with the number of whole chromosome gains or losses in the leukemia karyotype. Aneuploidy detectable by FCM was more frequent in acute lymphoblastic leukemia (ALL) (52 of 173, 30.1%) than in acute nonlymphoblastic leukemia (2 of 52, 3.8%) (p less than 0.001). In the ALL group, aneuploidy was significantly correlated with the cell surface expression of common ALL antigen: 46 of 127 antigen-positive cases were aneuploid compared to 6 of 46 antigen-negative cases (p less than 0.003). Only 2 of 21 cases of T-cell ALL without common ALL antigen had detectable aneuploidy, which was significantly less than in the common ALL group (p = 0.02). The median percentage of cells in S-phase was significantly greater for B-cell and erythrocyte rosette-positive T-cell ALL, than for the other phenotypic subgroups. We conclude that aneuploidy and S-phase cell percentage are correlated with the state of leukemia cell differentiation. The biologic basis for the correlation is not established, but may be linked to the process of malignant transformation.

Acute Disease↗

Near-haploid acute lymphoblastic leukemia: a unique subgroup with a poor prognosis?

We describe two adolescent girls with acute lymphoblastic leukemia (ALL) whose leukemia cells were near-haploid. Their lymphoblasts stained in a block pattern with periodic acid Schiff and had "common ALL" surface markers confirmed by indirect immunofluorescence. Each patient had two populations of blasts, one near-haploid and one hyperdiploid, which was an exact doubling of the near-haploid karyotype. The first patient had a predominant population of cells with 26 chromosomes and a few with 52, while the second had a predominance of cells with 56 and a minority with 28. Flow cytometric analysis of DNA content initially detected the minor near-haploid population in the second patient, which was confirmed later by cytogenetic review of the marrow sample. In addition to our two patients, only four patients have been reported with near-haploid ALL. Of these six, five were girls, five were adolescents, and five had short survivals (median, 10 mo). All six had disomy of chromosome 21 with or without disomy for chromosomes 10, 14, 18, or X (four patients each). Thus, near-haploid ALL may represent a unique subgroup of ALL with a poor prognosis. To detect these and other possible subgroups, we have included cytogenetic analysis and flow cytometric analysis of DNA content in our initial evaluation of patients with ALL.

Acute Disease↗

Clinical utility of initial terminal deoxynucleotidyl transferase determinations in childhood acute leukemias.

Terminal deoxynucleotidyl transferase (TDT) activity was measured in bone marrow lymphoblasts obtained at diagnosis from 168 consecutive patients with childhood acute leukemia. Absolute concentrations of TDT were increased (greater than or equal to 20 units/10(8) blasts) in samples from 98 of 112 assessable patients with acute lymphocyte leukemia (ALL). The values ranged from less than 1 to 1502 units/10(8) blasts with a median of 90 units contrasted with less than 1 to 219 units (median, 2.6 units) in studies of children without leukemia. Results of an immunofluorescence assay were in good agreement with enzymatic detection of the polymerase. Among 115 patients with adequate marrow smears, 105 had TDT-positive blasts. By contrast, in most children with acute myelogenous leukemia, TDT activity was either undetectable or less than 10 units/10(8) blasts. Although the highest levels of TDT were found in blasts with the common ALL phenotype, quantitative determinations were not significantly related to the major immunological subtypes of ALL or to morphological features or periodic acid-Schiff reactivity of the lymphoblasts. The probability that a newly diagnosed case of leukemia would be ALL was 90% if TDT levels were greater than 20 units/10(8) blasts. We conclude that absolute concentrations of TDT, as determined in this study, are of little value in identifying subclasses of ALL. The immunofluorescence assay, which is much less expensive and easier to perform than the enzyme assay, should prove useful for confirming the diagnosis of ALL and for detecting extramedullary sites of leukemic infiltration.

Acute Disease↗

Transient leukemoid reaction and trisomy 21 mosaicism in a phenotypically normal newborn.

Transient leukemoid reactions that resemble acute leukemia have been well described for infants with trisomy 21 (Down syndrome). We report a phenotypically normal 3-day-old boy with hepatosplenomegaly, leukocytosis, and circulating myeloblasts. On chromosome analysis, trisomy 21 was found in all blood and bone marrow cells. However, only 4% of cultured skin fibroblasts were trisomic and the other 96% were normal, thus indicating mosaicism. Without treatment, the leukocyte count gradually returned to normal and the organomegaly diminished. Subsequently, chromosome analysis of blood and bone marrow disclosed a predominance of cells with a normal karyotype. These findings suggest that mosaicism could be responsible for the transient leukemoid reactions in some newborns--i.e., the trisomic cells may temporarily gain a proliferative advantage over the normal cells, perhaps by inhibiting their growth. Serial cytogenetic studies, as well as chromosome analysis of more than one tissue, may help to distinguish transient leukemoid reactions from acute leukemia in infants.

Bone Marrow Cells↗

Activation of the alternative pathway of complement in childhood acute lymphoblastic leukemia.

Sequential studies in children with acute lymphoblastic leukemia have demonstrated that at diagnosis or relapse there is defective utilization of complement by the alternative pathway. Thus, the sera of 17/18 patients fail to completely consume C3 to C9 when incubated with zymosan or cobra venom factor (CoF). This underutilization is due to a specific inhibitor of C3 activation which has been partially isolated. By remission, the inhibotor disappears and the CoF and zymosan assays return to normal. In addition, serum levels of C3 and factor B are elevated at the time of diagnosis or relapse but fall to below 3 S.D. from the mean in nearly 60 per cent of the cases during induction therapy. Similarly, serum C4 levels which are normal at diagnosis fall to less that 3 S.D. from the mean in 7/12 cases during treatment. Low C3 levels correlate well with factor B values, suggesting that if C3 to C9 are utilized after the inhibitor has been eliminated, such utilization occurs primarily through the alternative pathway. Presumably, as illustrated by the low C4 levels, this activity is mediated by the ampliciation loop of the alternative pathway involving classical pathway generation of C3b.

Child↗

Cyclophosphamide/etoposide: effective reinduction therapy for children with acute nonlymphocytic leukemia in relapse.

Reinduction therapy consisting of cyclophosphamide (250 mg/m2 orally daily for 4 days) followed by etoposide (250 mg/m2 iv daily for 3 days) was administered to 14 children with refractory or recurrent acute nonlymphocytic leukemia. Five complete remissions were achieved in eight patients who had relapsed in the bone marrow 1-27 months after cessation of initial therapy, which included anthracyclines, cytarabine, etoposide, and 5-azacitidine. Reinduction attempts were unsuccessful in patients who had failed to achieve an initial remission and in those whose relapses occurred while receiving therapy. Toxicity, including myelosuppression and mucositis, was within acceptable limits. This drug combination deserves further assessment in therapeutic protocols for patients with acute nonlymphocytic leukemia.

Acute Disease↗