Search PubMed⌕ Search

Biomedical subjects

C P Steuber

Publications and source records attributed to C P Steuber.

At least 37 records · Page 2Linked to original sources
PubMed1993

Management of cytogenetic data in multi-center leukemia trials.

This paper provides methods for storing and retrieving cytogenetics data, which must reside jointly in a reference laboratory and in a data co-ordinating center. The major piece of data is the character string that uses the International System for Human Cytogenetic Nomenclature. Simple and complex data retrieval, using Statistical Analysis System (SAS) functions INDEX and SUBSTR, are illustrated. Use of the methods of this paper can save considerable costs in setting up cytogenetic data systems compared with other proposed systems which have come to the authors' attention.

Child↗
PubMed1993

Immunophenotypes and karyotypes of leukemic cells in children with Down syndrome and acute lymphoblastic leukemia.

PURPOSE: Immunophenotypes and karyotypes of leukemic cells were analyzed in a large series of Down syndrome patients with acute lymphoblastic leukemia (ALL) to examine the frequency of adverse prognostic features in comparison with other patients with ALL. PATIENTS AND METHODS: Presenting features and leukemic cell characteristics were compared for 76 patients with Down syndrome and 4,733 other patients with newly diagnosed ALL treated on protocols of the Pediatric Oncology Group (POG) and St Jude Children's Research Hospital (SJCRH). Treatment outcome was analyzed for the patients with non-T-cell disease enrolled on a single trial, for whom adequate follow-up data were available. RESULTS: Down syndrome patients had lower platelet counts (P < .01) and were less likely to have an anterior mediastinal mass (P < .01) or CNS leukemia (P = .01). They were significantly more likely to have the pre-B immunophenotype (49% v 25.5%, P < .01) and less likely to have T-cell ALL (5.5% v 16%, P = .01). There was a notable absence among patients with Down syndrome of the t(4;11), t(1;19), and t(9;22), which are chromosomal translocations associated with an adverse prognosis in ALL. Treatment outcome did not differ significantly between patients with Down syndrome and the other children with non-T-cell ALL (P = .21); a third of the treatment failures in the former group resulted from treatment-related toxicities. CONCLUSION: Children with Down syndrome and ALL had a low frequency of adverse clinicobiologic features at diagnosis. However, these findings did not translate into a superior outcome, apparently because of treatment-related toxicity in this group. Future trials should focus on pharmacokinetics and other strategies to reduce toxicity in these compromised patients.

Adolescent↗
PubMed1992

Trisomy of leukemic cell chromosomes 4 and 10 identifies children with B-progenitor cell acute lymphoblastic leukemia with a very low risk of treatment failure: a Pediatric Oncology Group study.

To account for the superior prognosis of hyperdiploid, B-progenitor acute lymphoblastic leukemia (ALL), we investigated the influence of trisomy in 1021 children greater than or equal to 1 year old by recursive partitioning analysis. The patients were treated according to a stratified, randomized study testing antimetabolite-based therapies. Trisomies of several individual chromosomes were associated with a better prognosis in a univariate statistical analysis. Of greater importance, trisomy of both chromosomes 4 and 10 identified a subgroup of patients (n = 180) with an extremely favorable 4-year event-free survival (EFS). Combined trisomy of chromosomes 4 and 10 retained its prognostic significance after stratification of patients by DNA index, age, and leukocyte count. Among patients with a DNA index greater than 1.16, patients with trisomies of both chromosomes 4 and 10 had a 4-year EFS of 96.6% (n = 161, SE = 3.8%), whereas patients with neither or only one of these trisomies had a 4-year EFS of 70.4% (n = 73, SE = 11.5%). All 19 patients with a DNA index less than or equal to 1.16 but with trisomies of chromosomes 4 and 10 remain in remission, suggesting that favorable chromosome trisomy dominates in a situation in which the cellular DNA content of less than or equal to 1.16 predicts a less favorable outcome. We conclude that combined trisomy of chromosomes 4 and 10 independently predicts EFS among children with B-progenitor ALL. Patients within the B-progenitor group who have this feature (about 20% of those with clonal abnormalities) are likely to be cured with antimetabolite-based chemotherapy--an approach that should produce few significant late effects.

Adolescent↗
PubMed1992

Soft-tissue sarcomas other than rhabdomyosarcoma in children.

Forty-seven children with nonrhabdomyosarcomatous soft-tissue sarcomas (NRSTS) were treated by the Hematology-Oncology Service at Texas Children's Hospital, Houston, Texas, between 1958 and 1990. The male:female ratio was 1:1, and the median age was 11 years (3 weeks-16 years). A preexisting condition was found in 9/47 (19%) patients including neurofibromatosis (3), Down's syndrome (1), spina bifida (1), congenital facial asymmetry (1), giant pigmented nevus (1), juvenile onset diabetes mellitus (1), and acquired immune deficiency syndrome (1). The site of primary tumor was head and neck (3), trunk (33), and extremities (11). Twenty-four patients (51%) have survived free of disease with a median follow-up of 5 years (4 months-22 years). No patient whose disease recurred achieved a second remission. Of the 19 patients with group I disease, 16 (84%) survived free of disease. Wide excision of the primary tumor, with no microscopic residual disease, was associated with the greatest chance of disease-free survival.

Adolescent↗
PubMed1992

Chronic relapsing thrombotic thrombocytopenic purpura in infants with large von Willebrand factor multimers during remission.

We studied two children with recurrent schistocytic hemolytic anemia and thrombocytopenia beginning in the neonatal period. One patient had a stroke during one of the episodes of thrombotic thrombocytopenic purpura. The presence of unusually large von Willebrand factor multimers was demonstrated in both children during clinical and hematologic remissions. Treatment with corticosteroids and intravenous injections of immune globulin was unsuccessful in the one patient who received it. Immediate improvement occurred in both patients after the infusion of fresh-frozen plasma. Symptoms of thrombocytopenia continue to recur at regular intervals in the absence of periodic fresh-frozen plasma infusions. One of these children apparently has chronic relapsing thrombotic thrombocytopenic purpura; the second has a chronic relapsing disorder similar to thrombotic thrombocytopenic purpura.

Blood Component Transfusion↗
PubMed1992

Expression of myeloid-associated and lymphoid-associated cell-surface antigens in acute myeloid leukemia of childhood: a Pediatric Oncology Group study.

PURPOSE: Although the expression of both myeloid- and lymphoid-associated cell-surface antigens in acute myeloid leukemia (AML) has been described, the clinical significance of such antigen expression remains unknown in the pediatric population. We sought to define an antibody panel for optimal diagnostic antigenic analysis and to test associations among antigen expression and a number of clinical features at presentation and prognosis in pediatric AML. PATIENTS AND METHODS: We reviewed the extensive immunophenotypic analysis performed at the time of diagnosis on 132 assessable patients registered on a single Pediatric Oncology Group AML protocol between 1984 and 1988. RESULTS: Eighty-eight percent of patients were identified by testing for expression of CD33 and CD13. Overall, 61% of patients expressed at least one lymphoid-associated antigen, most commonly CD4, CD7, or CD19. Expression of CD5, CD10, CD20, or CD22, commonly detected in T- or B-lineage pediatric acute lymphoid leukemia (ALL), was uncommon; coexpression of multiple lymphoid-associated antigens was also uncommon. Expression of the monocyte-associated antigen CD14 correlated with French-American-British (FAB) M4 or M5 morphology. Otherwise, no correlation between antigen expression and FAB classification was noted. None of the myeloid, lymphoid, natural-killer (NK), or progenitor-associated antigens were associated with significant differences in the likelihood of remission induction or event-free survival when expressor versus nonexpressor groups were compared. CONCLUSIONS: The distribution of cell-surface antigen expression in pediatric acute leukemia usually permitted the discrimination of AML from ALL by using a limited panel of antibodies. Although the expression of lymphoid-associated antigens was common, such expression did not seem to be associated with an adverse prognosis in pediatric AML.

Acute Disease↗
PubMed1991

Clinical characteristics and treatment outcome of childhood acute lymphoblastic leukemia with the t(4;11)(q21;q23): a collaborative study of 40 cases.

The t(4;11)(q21;q23) chromosomal abnormality was identified in 40 (2%) of 1,986 children with newly diagnosed acute lymphoblastic leukemia (ALL). This translocation was associated with female sex (63%), age less than 1 year (60%), hyperleukocytosis (median leukocyte count, 156.5 x 10(9)/L), CD10-/CD19+ B-precursor cell immunophenotype, and myeloid-associated antigen (CD15) expression (63%). Nearly all cases had at least some CD24- blast cells. The CD10-/CD15%/CD19+/CD24/+ phenotype was found in 20 of the 32 t(4;11) cases tested. None of the 40 cases had the cytogenetic finding of hyperdiploidy greater than 50, which is a favorable prognostic feature. For clinical comparison, the t(4;11) cases were divided into three groups according to age at diagnosis: less than 1 year (n = 24), 1 to 9 years (n = 8), and greater than or equal to 10 years (n = 8). Compared with older patients, infants were more likely to have initial central nervous system leukemia (P = .05) and less likely to have pre-B-cell ALL (P = .05). Complete continuous remission has been maintained in only 7 of 24 infants and 2 of 8 patients aged greater than or equal to 10 years, in contrast to 7 of 8 children in the intermediate age group (P = .048). These findings suggest that the t(4;11) is an adverse prognostic feature in these two age groups.

Adolescent↗
PubMed1991

Toxicity trials of amsacrine (AMSA) and etoposide +/- azacitidine (AZ) in childhood acute non-lymphocytic leukemia (ANLL): a pilot study.

Recurrent or induction therapy-resistant ANLL carries a grave prognosis. The combination of AMSA at 100 mg/M2 daily for 5 days and etoposide at 200 mg/M2 daily for the first 3 days of therapy was given to 40 patients with refractory ANLL. An additional 17 patients received those two agents plus azacitidine at a dosage of 250 mg/M2 on days 4 and 5. All three drugs were given as one-hour infusions. All patients had normal electrolyte determinations daily and were on cardiac monitors during the period of drug administration. No arrhythmias were detected in 522 doses of AMSA. Toxicities observed were primarily related to myelosuppression. Forty-nine of the 57 patients required hospitalization for suspected or proven infection. Nausea/vomiting and mucositis were the next most commonly occurring toxicities. Responses were seen in 22 patients.

Adolescent↗
PubMed1991

Essential thrombocythemia in a child: management with anagrelide.

Essential thrombocythemia (ET) is a rare disorder in children. An 11-year-old white boy was first seen in January 1986 with symptoms of abdominal pain. His platelet count was 1.5 million/mm3. Other hematological values and coagulation studies, including bleeding time, were normal. There was laboratory evidence of mild platelet dysfunction. Using the criteria of the Polycythemia Vera Study Group, a diagnosis of ET was made. He developed frequent headaches. Aspirin was prescribed for the next 2 years at varying doses and frequency. During the period, platelet counts ranged between 1 and 3 million/mm3. In view of progressive headaches and evidence of increasing platelet dysfunction, further treatment was indicated. The use of a new agent, anagrelide, reported effective in adults with ET, resulted in amelioration of symptoms and improvement in quantitative and qualitative platelet control with no significant untoward effects.

Aspirin↗
PubMed1991

Functional deficiency of protein C associated with mesenteric venous thrombosis and splenic infarction.

A 16-year-old girl had abdominal pain, hematemesis, and fever. Radiographic evaluation showed her to have an infarcted spleen and jejunum. Pathologic description revealed thrombi involving the vessels of both organs. A hypercoagulation evaluation of the patient and her family resulted in the diagnosis of hereditary protein C activity deficiency. She is unusual both in the diagnosis of protein C activity deficiency and in her appearance with mesenteric and splenic venous thrombosis. This appearance has not been previously reported in the literature and should be considered in the differential diagnosis of any thrombotic event, even in the face of a negative family history.

Adolescent↗
PubMed1991

A comparison of induction and maintenance therapy for acute nonlymphocytic leukemia in childhood: results of a Pediatric Oncology Group study.

Two hundred fifty-six children with previously untreated acute nonlymphocytic leukemia (ANLL) were evaluated on a Pediatric Oncology Group (POG) phase III randomized trial of both induction and continuation chemotherapies. Induction therapy compared vincristine, cytarabine, and dexamethasone (VADx) with daunorubicin, cytarabine, and thioguanine (DAT). The complete remission (CR) rate using DAT was superior (82% v 61%, P = .02). Postremission therapy consisted of either "standard" two-cycle therapy or a more intensive four-cycle regimen given for 2 years. Overall, there was no difference in outcome for patients randomized to either continuation regimen. The overall complete continuous remission rate (CCR) for the "best" induction/continuation therapy combination at 2 years was .50 (SE = .06), at 3 years was .35 (.04), and at 4 years was .34 (.05). Analysis of selected clinical and laboratory parameters demonstrated differences in induction responses favoring DAT induction but did not impact eventual disease-free survival. There were two subgroups of patients who responded better to four-cycle continuation therapy. These were patients with French-American-British (FAB) M1/M2 (2-year CCR was .20 v .44, P = .01) and patients older than 10 years at diagnosis (.32 v .62, P = .004).

Agranulocytosis↗
PubMed1991

High-dose cytarabine for intensification of early therapy of childhood acute myeloid leukemia: a Pediatric Oncology Group study.

In June 1984, the Pediatric Oncology Group (POG) initiated a pilot study (8498) using high-dose cytarabine (HdA; 3 g/m2) for intensification of early therapy in childhood acute myelogenous leukemia (AML) (group I). Remission induction therapy consisted of two courses of daunorubicin, cytarabine (Ara-C), and thioguanine (DAT). Postremission therapy consisted of four sequential courses, each consisting of (1) four doses of HdA (HdA4) followed by asparaginase (L-Asp), (2) etoposide (VP) plus azacytidine (Az), (3) prednisone, vincristine, methotrexate, and mercaptopurine (POMP), and (4) Ara-C daily for 5 days by continuous infusion. Six doses of intrathecal Ara-C were given for CNS prophylaxis. In December 1986, the protocol was amended (group II) to substitute six doses of HdA (HdA6) for the second DAT (two + five) induction course; postinduction, a single course of HdA6 was given instead of four HdA/L-Asp courses, and the remainder of the therapy was unchanged. One hundred forty group I patients and 145 group II patients were assessable. The two groups were similar with regard to clinical prognostic groups. No significant differences were noted in the two groups with regard to remission induction (85% [SE = 2%] in each group), induction deaths (6.5% v 7.0%), or deaths in remission (one in each group). Cerebellar toxicity was reported in three patients in group II (with HdA6) but none in group I (HdA4). At present, patients who received HdA6 (group II) had higher event-free survival than patients in group I (EFS at 3 years, 34% [SE = 11%] v 29% [SE = 4%]), and disease-free survival (DFS at 3 years, 42% [SE = 14%] v 34% [SE = 4%]), but the differences were not statistically significant. In both groups, children less than 2 years and those with WBCs less than 100,000/microL had significantly better outcome (EFS of 55% [SE = 10%] and 36% [SE = 5%] at 3 years, respectively) than children greater than or equal to 2 years and those with WBCs greater than or equal to 100,000/microL (EFS of 27% [SE = 5%] and 20% [SE = 9%] at 3 years, respectively.

Adolescent↗
PubMed1990

Bone marrow transplantation in childhood leukemia using reverse isolation techniques.

Between 1979 and 1986, 29 pediatric patients underwent bone marrow transplantation at Texas Children's Hospital using routine reverse isolation. Laminar air flow rooms, prophylactic antibiotics, and gut sterilization were not utilized. The diagnoses included acute lymphocytic leukemia (ALL) (16 patients), acute nonlymphocytic leukemia (ANLL) (10 patients), and chronic myelogenous leukemia (CML) (three patients). All patients had fever during hospitalization. There were 11 episodes of bacteremia in seven patients giving a bacteremia rate of 37.9%. Moderate-to-severe (grade II-IV) acute graft-versus-host disease (GVHD) was seen in eight patients (27.6%). The incidence of infection and GVHD during the first 100 days post-transplantation is comparable to published reports from centers utilizing rigid isolation and sterilization of the gut. It is suggested that bone marrow transplantation may be done using standard reverse isolation techniques without increasing the morbidity or mortality of the procedure.

Adolescent↗
PubMed1990

Aziridinylbenzoquinone (AZQ) in the treatment of recurrent pediatric brain and other malignant solid tumors. A Pediatric Oncology Group phase II study.

To assess the response rates and toxicity of AZQ in children with recurrent brain and other malignant solid tumors, a phase II study was implemented by the Pediatric Oncology Group. Eligible patients received AZQ 18 mg/M2/week i.v. for 4 doses followed by a 2 week rest period. Each dose was given over four hours (1/3 over the initial 20 minutes). After the first year, the dosage was reduced to 13 mg/M2 due to myelotoxicity resulting in treatment delays. No objective responses were observed in 73 evaluable children with various non-central nervous system tumors. Of the 91 patients with brain tumors, there were 4 CR's and 2 PR's in patients with astrocytoma, ependymoma, glioblastoma multiforme, oligodendroglioma, brain stem glioma and intracranial yolk sac tumor (median duration, 10 months; range, 2-20+ months). Three of 4 CR's were achieved with a dosage of 18 mg/M2/week. An additional 13 children with brain tumors experienced stable or improved disease (duration, 2-36 + months; median 7.5 months). The principal toxicity was myelosuppression which was cumulative but there were also 3 allergic reactions to AZQ. We conclude that for selected brain tumors, the rates of objective response and stable disease plus the duration of responses support further assessment of AZQ in combination with other agents. Furthermore, the 18 mg/M2 dosage may provide better responses.

Adolescent↗
PubMed1990

Pyoderma gangrenosum in childhood leukemia.

A case of pyoderma gangrenosum (PG) in a 14-year-old boy with acute myelogenous leukemia (AML) is described. The onset of pyoderma gangrenosum coincided with the relapse of AML. The lesions responded dramatically to treatment with oral prednisone despite the persistence of leukemia. Pyoderma gangrenosum should be included in the differential diagnosis of any nodular, pustular, or necrotic cutaneous eruption in children with leukemia.

Adolescent↗
PubMed1989

Long-term results in the treatment of acute nonlymphocytic leukemia: a Pediatric Oncology Group Study.

Complete remission (CR), 5-year remission duration (RD), and overall 5-year survival rates are 74%, 28% and 25%, respectively, for previously untreated children with acute nonlymphocytic leukemia diagnosed between 1977 and 1981, following induction therapy with vincristine, doxorubicin and prednisone (VAP), consolidation therapy with 6-thioguanine, cytosine arabinoside (TA) and cyclophosphamide/vincristine/cytosine arabinoside/prednisone (COAP), and maintenance therapy of alternating TA and COAP with or without VAP pulses. Approximately 20% are free of their disease for more than 5 years. High white blood cell counts (WBC) at diagnosis and M3 and M6 morphology were associated with lower CR rates, while M5 morphology was associated with higher CR rates. Patients with M1 morphology had shorter remission duration as compared to those with M4 or M5 morphology. Low WBC and age between 2 and 10 years at diagnosis were associated with longer remission durations and survival. Patients with M4 morphology also survived longer. The observed CR rates are comparable to other studies initiated at the same time as this study but survival is less than those reported more recently. Low WBC at diagnosis and M4/M5 morphology may identify relatively favorable prognostic groups.

Adolescent↗
PubMed1989

Acquired immune deficiency, myelodysplasia, and acute nonlymphocytic leukemia associated with monosomy 7 and t(3;3) (q21;q26) in a child with Langerhans cell histiocytosis.

A case of therapy-related myelodysplasia followed by acute nonlymphocytic leukemia in a 5-year-old child successfully treated for diffuse Langerhans cell histiocytosis is described. A syndrome of severe cell-mediated immune deficiency and persistent Epstein-Barr virus (EBV) infection coincided with the evolution of myelodysplasia. Specific abnormalities of chromosomes number 7 and 3 were associated with the onset of myelodysplasia and acute nonlymphocytic leukemia and are believed to be linked to the patient's immune dysfunction and compromised ability to contain viral infection.

Chlorambucil↗