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T Vietti

Publications and source records attributed to T Vietti.

At least 19 recordsLinked to original sources
PubMed1998

Conduct of phase I trials in children with cancer.

PURPOSE AND METHODS: Future progress in the care of children with cancer requires appropriate evaluations of promising new agents for pediatric indications, beginning with well-conducted phase I trials. This report summarizes current guidelines for the conduct of pediatric phase I trials and represents a consensus between American and European investigators. The primary objective of pediatric phase I trials is to define safe and appropriate doses and schedules of new agents that can subsequently be used in phase II trials to test for activity against specific childhood malignancies. Prioritization of agents for evaluation in children is critical, since many more investigational agents are evaluated in adult patients than can be systematically evaluated in children. Considerations used in prioritizing agents include activity in xenograft models, novel mechanism of action, favorable drug-resistance profile, and activity observed in adult trials of the agent. RESULTS AND CONCLUSION: Distinctive characteristics of pediatric phase I trials, in comparison to adult phase I trials, include the necessity for multiinstitutional participation and their higher starting dose (typically 80% of the adult maximum-tolerated dose [MTD]), both of which reflect the relative unavailability of appropriate patients. The application of uniform eligibility criteria and standard definitions for MTD and dose-limiting toxicity (DLT) help to assure that pediatric phase I trials are safely conducted and reliably identify appropriate doses and schedules of agents for phase II evaluation. Where possible, pediatric phase I trials also define the pharmacokinetic behavior of new agents in children.

Antineoplastic Agents↗
PubMed1998

Phase I trial of 9-aminocamptothecin in children with refractory solid tumors: a Pediatric Oncology Group study.

PURPOSE: A phase I trial of 9-aminocamptothecin (9-AC) was performed in children with solid tumors to establish the dose-limiting toxicity (DLT), maximum-tolerated dose (MTD), and the pharmacokinetic profile in children and to document any evidence of activity. PATIENTS AND METHODS: A 72-hour infusion of 9-AC dimethylacetamide formulation was administered every 21 days to 23 patients younger than 21 years of age with malignant tumors refractory to conventional therapy. Doses ranged from 36 to 62 microg/m2 per hour. Pharmacokinetics were to be performed in at least three patients per dose level. The first course was used to determine the DLT and MTD. RESULTS: Nineteen patients on four dose levels were assessable for toxicities. At 62 microg/m2 per hour, three patients experienced dose-limiting neutropenia and one patient experienced dose-limiting thrombocytopenia. Pharmacokinetics were performed on 15 patients (nine patients had complete sets of plasma sampling performed). The pharmacokinetics of both lactone and total 9-AC were highly variable. The percentage of 9-AC lactone at steady-state was 10.8% +/- 3.6%. Total 9-AC and its lactone form had a terminal half-life of 8.1 +/- 3.8 and 7.1 +/- 3.9 hours, respectively, and a volume of distribution at steady-state (Vdss) of 21.2 +/- 13.3 L/m2 and 135.3 +/- 52.5 L/m2, respectively. Hepatic metabolism and biliary transport had an important role in 9-AC disposition. CONCLUSION: The recommended phase II dose of 9-AC administered as a 72-hour infusion every 21 days to children with solid tumors is 52 microg/m2 per hour. Neutropenia and thrombocytopenia were dose limiting.

Adolescent↗
PubMed1997

Preservation of the bladder in patients with rhabdomyosarcoma.

PURPOSE: To review the pathologic findings from children with gross residual rhabdomyosarcoma (RMS) of the bladder and compare the treatment outcome of those who underwent cystectomy with those who did not. PATIENTS AND METHODS: Primary and follow-up records and pathology specimens for 28 patients with gross residual disease entered onto the intergroup Rhabdomyosarcoma Study (IRS) III were reviewed. These patients were assigned to receive 20 weeks of multiagent induction chemotherapy and 4 weeks of radiotherapy. Future therapy decisions were based on clinical and histologic evaluation at 20 weeks. RESULTS: All patients had a clinical and histologic response. Thirteen patients underwent cystectomy at intervals that ranged from 1.5 to 38 months after the start of therapy. All but one patient are alive and well without recurrence. Reasons for cystectomy included presumed evidence of tumor growth from imaging studies, findings at cystoscopy, or histologic interpretation of biopsies. In 12 of 14 specimens from 15 patients who retained their bladder, no tumor cells were seen at first or second evaluation. In cystectomy specimens, tumor cellularity was markedly reduced and all tumor cells were in varying degrees of cellular maturation. Review of primary tumor specimens showed a greater degree of cellular maturation in patients with retained bladders than in those who underwent cystectomy. CONCLUSION: Bladder RMS is responsive to chemotherapy and radiotherapy. Twelve of 26 patients showed complete loss of tumor cells after induction therapy. Cystectomy specimens showed diminished tumor cells with varying degrees of cellular maturation. It is hypothesized that these tumors may have shown further maturation and ultimate loss of matured cells with continuing therapy.

Child↗
PubMed1996

The importance of phase I/II trials in pediatric oncology.

Clinical trials in pediatric oncology over the past 30 years have led to the situation today where most children with newly diagnosed cancer can be treated effectively, and many are cured. Despite this dramatic improvement in outcome for many children diagnosed with cancer, about 30-40% of children will die of their disease [1]. Although some attempts have been made to improve outcome by increasing the dose intensity of existing therapies, intolerable side effects and marginal increases in cancer cell kill limit this approach. Clearly, effective new anti-cancer agents are necessary to significantly improve the survival and quality of life in children with cancer. Well-organized pediatric Phase I trials to establish the maximum tolerated dose (MTD), and Phase II trials to establish efficacy, are critical to the identification of new anti-cancer agents.

Antineoplastic Agents↗
PubMed1996

Results of a prospective randomized trial comparing standard dose neuraxis irradiation (3,600 cGy/20) with reduced neuraxis irradiation (2,340 cGy/13) in patients with low-stage medulloblastoma. A Combined Children's Cancer Group-Pediatric Oncology Group Study.

PURPOSE: To determine in a prospective randomized trial the effect on survival, progression-free survival, and patterns of relapse of a decrease in the neuraxis radiation dose from 3,600 cGy in 20 fractions to 2,340 cGy in 13 fractions in patients with newly diagnosed medulloblastoma between 3 and 21 years of age with low T stage (T1, T2 and T3A), minimal postoperative residual tumor, and no evidence of dissemination (M0). METHODS AND MATERIALS: Between June 1986 and November 1990, the Children's Cancer Group and the Pediatric Oncology Group randomized 126 patients in a two-arm study comparing the two different doses of neuraxis irradiation. In both arms, the posterior fossa received 5,400 cGy in 30 fractions. All patients were staged with myelography, postoperative lumbar cerebrospinal fluid cytology, and postoperative contrast-enhanced cranial computerized tomography to ensure no evidence of dissemination and no more than 1.5 cm3 residual tumor volume. Overall survival, progression-free survival, and patterns of recurrence were carefully monitored. Prospective endocrine and psychometric studies were performed to determine the benefit of decreasing the neuraxis radiation dose. RESULTS: Following an interim analysis at a median time on study of 16 months, the study was closed, since a statistically significant increase was observed in the number of all relapses as well as isolated neuraxis relapses in patients randomized to the lower dose of neuraxis radiation. CONCLUSIONS: In patients with newly diagnosed medulloblastoma considered to have a good prognosis on the basis of low T stage, minimal residual tumor after at least subtotal resection, and no evidence of dissemination after thorough evaluation, there is an increased risk of early relapse associated with lowering the dose of neuraxis radiation from 3,600 cGy in 20 fractions to 2,340 cGy in 13 fractions.

Adolescent↗
PubMed1995

A phase I study of acivicin in refractory pediatric solid tumors. A Pediatric Oncology Group study.

Forty-two patients with progressive solid tumors and brain tumors were entered in this Phase I study of the glutamine antagonist acivicin given intravenously over thirty minutes daily for five days. The major toxicities encountered were myelosuppression and central nervous system toxicity (nightmares and somnolence). The maximum tolerated dosage on this schedule was 26 mg/M2 daily for five days. Six patients including three patients with brain tumor had stable disease.

Adolescent↗
PubMed1995

Cyclophosphamide dose escalation in combination with vincristine and actinomycin-D (VAC) in gross residual sarcoma. A pilot study without hematopoietic growth factor support evaluating toxicity and response.

PURPOSE: The Intergroup Rhabdomyosarcoma Study (IRS) initiated an escalating-dose cyclophosphamide (Cyc) pilot without hematopoietic growth factor (HGF) support in combination with vincristine (Vcr) and actinomycin-D (Amd), known as VAC, to establish a Cyc dose with myelotoxicity comparable to an ifosfamide (Ifos), Vcr, and Amd combination regimen (VAI). A Cyc dose equivalent to Ifos was to be determined when comparable myelotoxicity was achieved. PATIENTS AND METHODS: Patients with either rhabdomyosarcoma or undifferentiated soft-tissue sarcoma and gross residual (clinical group III) disease were eligible for the VAC pilot. Feasibility and toxicity were evaluated in the VAC pilot at each Cyc level before escalating the dose. Starting at CYC 1.2 g/m2 dose escalation was planned at increments of 20-25% in cohorts of 8-10 patients until myelotoxicity at a severe or worse grade was seen in > 90% of the patients. RESULTS: One hundred nineteen eligible patients were evaluated for toxicity and response at four Cyc levels: 1.2, 1.5, 1.8, and 2.2 g/m2. Eight of 87 (9%) evaluable at 2.2 g/m2 had a toxic death. Six of these were attributable to myelotoxicity. Patients age 1-3 years were most vulnerable. The overall complete response (CR) rate of 68% was poorly predicted by the weeks 8 and 20 CR rates of 20 and 40%, respectively. During the first year and overall, myelotoxicity at 2.2 g/m2'1 with VAC was comparable to Ifos 1.8 g/m2'5. Cyc was relatively more myelotoxic than Ifos in the second year of the VAC pilot. Based on actual amount of drug given, a standardized Ifos dose of 9.0 g/m2 was equivalent to 2.1 g/m2 of Cyc, giving an Ifos/Cyc ratio of 4.3. CONCLUSION: Myelotoxicity using 2.2 g Cyc/m2 in a single intravenous infusion was dose limiting in this VAC pilot without HGF. In the first year and overall, myelotoxicity is comparable to that with VAI using Ifos at 9.0 g/m2. An ongoing IRS-IV randomized trial of VAC and VAI should provide a comparison of the efficacy of Ifos and Cyc in children and adolescents with embryonal or alveolar rhabdomyosarcoma and undifferentiated soft-tissue sarcomas.

Adolescent↗
PubMed1994

Acute myeloid leukemia in patients treated for rhabdomyosarcoma with cyclophosphamide and low-dose etoposide on Intergroup Rhabdomyosarcoma Study III: an interim report.

The early occurrence of five cases of acute myeloid leukemia (AML) in children treated for primary rhabdomyosarcoma on the Intergroup Rhabdomyosarcoma Study III (IRS III) has prompted this report. These patients received cyclophosphamide and four received etoposide in addition to other agents. There were 1,062 eligible patients entered on IRS III between 1984 and 1991. Following surgery, treatment consisted of multiagent chemotherapy and radiotherapy in select clinical groups. Median follow-up time is 3.7 years (range 0-7.4 years). Incidence densities and odds ratios for AML were calculated for various treatment groups. Five cases of secondary AML have been reported through August 1992. A single case of osteogenic sarcoma was reported in the same period and a patient with myelodysplastic syndrome has occurred since that time. Median time to development of AML was 39 months. Incidence density of AML for patients receiving neither cyclophosphamide nor etoposide was 0, for those receiving cyclophosphamide but no etoposide it was 7.6, and when both agents were given, it was 51.6. The odds ratios of AML for the latter two groups indicated a risk of AML which was seven times higher in the patients who received both agents. A history of breast cancer was present in all five families of patients with AML and several other cancers had occurred in three families. Preliminary analysis suggests a possible causal role for low-dose etoposide in addition to that assumed for cyclophosphamide in the early development of AML among pediatric patients treated for rhabdomyosarcoma.

Adolescent↗
PubMed1994

Prognostic features of Ewing's sarcoma on radionuclide bone scan after initial treatment.

OBJECTIVE: To study short-term changes in the radiopharmaceutical bone scan (BS) appearance of Ewing's sarcoma for indicators of decreased survival or future disease progression. METHODS: One-hundred and four patients with non-metastatic Ewing's sarcoma were evaluated at three time points: time of diagnosis (pre-biopsy), after induction chemotherapy (13 weeks) and after radiation therapy (20 weeks). Radiographs, computed tomograms (CTs) and BSs were obtained at each interval. Primary lesion activity and size on BS were evaluated and compared to radiographic and CT findings. RESULTS: No significant relationship was found at any time point between absolute radiopharmaceutical activity within the primary lesion and either disease progression or patient survival. Relative changes in BS activity between time points were also not significantly related to disease progression or survival despite a significant decrease in activity among the three time points. The size of the BS abnormality compared to the CT abnormality at the primary lesion site was related to both survival and disease progression at the post-induction chemotherapy time point (P = 0.025 and P = 0.014, respectively) with larger BS abnormalities indicating worse prognosis and survival. This relationship lost its significance at the post-radiation time point. No other significant relationship between the relative size of the BS abnormality and the size of the plain radiographic or CT abnormality was detected. CONCLUSION: Our data suggest that BS imaging of the primary lesion of Ewing's sarcoma provides little information in terms of predicting long-term survival or disease progression in patients with non-metastatic Ewing's sarcoma.

Adolescent↗
PubMed1992

Serum lactate dehydrogenase in childhood neuroblastoma. A Pediatric Oncology Group recursive partitioning study.

On the basis of an extensive recursive partitioning analysis of 668 patients with newly diagnosed neuroblastoma registered on Pediatric Oncology Group (POG) studies between October 1981 and May 1987, four major subsets of patients were created. Important prognostic factors included the patient's stage of disease, age, and level of serum lactate dehydrogenase (LDH). After adjusting for these factors, no other clinical prognostic factors were significant. The implications for protocol design are that (a) fine tuning of current therapy should be sought for the two favorable disease patient subsets, while (b) novel aggressive therapies are needed for the two unfavorable disease patient subsets where the overwhelming majority are dying. This article may serve as a model for others investigating prognostic factors. The data were divided into two subsets: one was used for an exploratory analysis; the other was used to confirm the exploratory findings. Despite spite the large number of statistical tests performed, the likelihood that the findings can be attributed to chance can be dismissed as virtually zero.

Adolescent↗
PubMed1991

High-dose cyclophosphamide-high-dose methotrexate with coordinated intrathecal therapy for advanced nonlymphoblastic lymphoma of childhood: results of a Pediatric Oncology Group study.

The Pediatric Oncology Group (POG) investigated a high-dose cyclophosphamide (CPM) high-dose methotrexate (MTX) regimen to determine therapeutic efficacy in confirmed advanced nonlymphoblastic non-Hodgkin's lymphoma (NHL) (stages III and IV) and B-cell acute lymphatic leukemia (B-ALL) in children. Another goal was to determine the comparative effectiveness of shortened maintenance treatment (2 versus 6 courses) in the study population. Systemic induction therapy included vincristine, prednisone, cyclophosphamide, and intermediate-dose MTX with leucovorin rescue. Superimposed intrathecal (IT) therapy included cytosine arabinoside for 2 successive days followed on day 3 by MTX. Intrathecal MTX was given 3 times during induction. At the end of induction, 2 days of triple (hydrocortisone, MTX, and cytosine arabinoside) therapy were given intrathecally (TIT). All patients then received a consolidation course of 4 doses of TIT, 2 doses of cyclophosphamide, and 4 more courses of vincristine and MTX with leucovorin rescue. Patients were then randomized to receive either 2 or 6 cycles of vincristine plus MTX with leucovorin rescue. The TIT was given with each cycle. Complete response rates by histology and Murphy stage (1) were as follows: undifferentiated lymphoma (DUL) stage III, 84/105 (80%): stage IV, 5/12 (42%); and other NHL [primarily large cell lymphoma (LCL)] stage III, 21/28 (75%); stage IV, 2/3 (67%). Event-free survival (EFS) at greater than 2 years was similar for patients with DUL and LCL, i.e., 65 and 61%, respectively. No significant difference in outcome was noted between patient groups receiving 2 or 6 maintenance treatments (p = .76). Treatment was notable for its modest toxicity following the early change to single-dose CPM therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1989

Prognostic importance of the pre-B-cell immunophenotype and other presenting features in B-lineage childhood acute lymphoblastic leukemia: a Pediatric Oncology Group study.

We report the prognostic significance of the pre-B-cell immunophenotype and other presenting features, including blast cell karyotype, in a randomized clinical trial conducted from 1981 to 1986 for children with early pre-B (n = 685) or pre-B (n = 222) acute lymphoblastic leukemia (ALL). Patients greater than or equal to 1 year and less than or equal to 21 years of age who attained complete remission were stratified by conventional risk criteria and immunophenotype and then randomized to receive continuation therapy with either of two regimens of intensive chemotherapy, designated S (standard) and SAM (standard plus intermediate-dose methotrexate, 1 g/m2 every 8 weeks). The proportions of subjects achieving complete remission in the two phenotypically defined subgroups were identical, 96%. At a median follow-up time of 42 months, the overall probability of 4-year event-free survival (+/- SE) was 63% +/- 2% (pre-B = 51% +/- 5% and early pre-B = 66% +/- 3%). Children with pre-B ALL had significantly shorter durations of continuous complete remission (P = .0004); this association included both bone marrow and CNS remissions (P = .0004 and P = .02, respectively). In a univariate Cox regression analysis of potentially important prognostic factors, the pre-B immunophenotype was significantly related to a poorer outcome, as were other recognized biologic and clinical features (eg, pseudodiploidy, older age, male sex, black race, and a higher WBC). It retained its prognostic strength in a multivariate model based on age, WBC, ploidy, and sex. The risk of failure at any point in the clinical course of a child with the pre-B immunophenotype was 1.8 times as great as that in a patient lacking this feature but otherwise having an equivalent risk status. It should be stressed that the predictive value of any of the significant characteristics identified in this study could diminish in the context of another, more effective treatment program. Nevertheless, our major conclusion, that children with pre-B ALL fare worse than those with early pre-B disease in a contemporary clinical trial has implications for stratified randomization of patients and the design of risk-specific treatment protocols.

Analysis of Variance↗
PubMed1986

Natural history of histiocytosis X: a Pediatric Oncology Group Study.

The best therapy for patients with histiocytosis X with disease involvement other than isolated bone lesions but without organ dysfunction is unclear. This retrospective study was undertaken to define the natural history of this group of patients. In 25 of the 92 studied patients, there was no progression of the disease after diagnosis. In 53 surviving patients, the disease either continuously progressed (40) or recurred intermittently (13). The onset of last disease activity was 24 months or less for 55% of these children. A fatal outcome occurred in 14 children. All of these children developed organ dysfunction and 11/14 died during or before the second year of disease. These three different outcomes could not be predicted from the parameters evaluated; however, the disease that never abated but was continuously active was associated with a suboptimal outcome, and the development of organ dysfunction was a grave prognostic sign.

Adolescent↗
PubMed1986

Clinical and biologic features predict poor prognosis in acute lymphoid leukemias in children and adolescents: a Pediatric Oncology Group review.

Although the prognosis of children with ALL has improved markedly, approximately one-half of children continue to relapse. Clinical and biologic features of ALL have been studied at the time of diagnosis and many of these features have been shown to predict the risk of relapse, permitting tailoring of therapy based on relapse hazard. Results of studies of the Pediatric Oncology Group (POG) detailed here demonstrate that high white blood cell (WBC) count at diagnosis, very young or older age within childhood, and the presence of a mediastinal mass or central nervous system leukemia predict a poor prognosis within the context of certain therapies. However, not only age and WBC count, but immunophenotype of ALL as well, were especially predictive of prognosis in these POG studies. The information reviewed here has special importance for the planning of clinical trials for children with ALL.

Adolescent↗
PubMed1985

Comparison of cytotoxicity of single dose and infusion of alkylating agents.

Both cytotoxicity and host toxicity were examined for the alkylating agents HN2, BCNU and L-PAM administered intravenously (IV) either as a single bolus injection or a 24-hour infusion. The bolus injection was more effective than the infusion schedule at a given dose for BCNU and L-PAM. Unexpectedly, the HN2 infusion schedule was more effective than bolus injection at a given dose. When host survival was the endpoint, both HN2 and L-PAM were shown to be more effective by the infusion schedule.

Alkylating Agents↗