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Biomedical subjects

R D Gelber

Publications and source records attributed to R D Gelber.

At least 109 records · Page 6Linked to original sources
PubMed1994

The International (Ludwig) Breast Cancer Study Group Trials I-IV: 15 years follow-up.

BACKGROUND: Adjuvant systemic therapy prolongs disease-free and overall survival in both pre- and postmenopausal patients. Available data shown benefit from multi-agent chemotherapy, prolonged tamoxifen treatment, and ovarian ablation, and that the combination of chemo- and endocrine therapy might be advantageous. In 1978 the International (Ludwig) Breast Cancer Study Group (IBCSG) initiated four complementary randomized controlled clinical trials to evaluate the roles of chemo-endocrine combinations or endocrine therapy alone in specific populations defined by risk (for pre- and perimenopausal patients) or by age (for postmenopausal patients). The results at 10 and 13 years' median follow-up for these trials are summarized in this report and are compared to those of the Overview meta-analysis with regard to chemo-endocrine or endocrine therapy combinations. Furthermore, types of first relapses by sites and second malignant diseases are reported. PATIENTS AND METHODS: 1601 evaluable patients with node positive disease were included into the studies I-IV. In Trial I (491 premenopausal patients with 1-3 positive axillary nodes) we studied the addition of low-dose continuous prednisone (p) to a cyclophosphamide-methotrexate-fluorouracil (CMF) combination. In Trial II 327 premenopausal patients with four or more positive axillary nodes were randomized to one year CMFp or to a surgical oophorectomy followed by CMFp. In Trial III (463 postmenopausal patients 65 years old or younger), combined chemoendocrine therapy (one year of CMFp plus tamoxifen (T)) was compared to endocrine therapy (1 year of p + T) or to surgery alone. In Trial IV 320 postmenopausal patients 66 to 80 years old were treated either by surgery alone or by surgery followed by 1 year prednisone and tamoxifen. RESULTS: In Trial I the addition of prednisone allowed a higher dose of cytotoxics to be administered compared with CMF alone. Despite this increased dose intensity, 13-year disease-free survival (DFS) and overall survival (OS) were similar for the two treatment groups (49% vs. 52% DFS, 59% vs. 65% OS for CMFp vs. CMF). In Trial II the addition of surgical oophorectomy to CMFp yielded an improved outcome which approached statistical significance for the subset of 107 patients known to have estrogen receptor-positive tumors (DFS, 23% vs. 15%, p = 0.13; OS, 41% vs. 30%, p = 0.12). In Trial III combined chemoendocrine therapy improved DFS and OS compared with endocrine therapy alone (p + T) given for the same duration, or no adjuvant treatment (DFS, 35% vs. 25% vs. 14%, p < 0.0001; OS, 48% vs. 36% vs. 32%, p = 0.01). In Trial IV p + T improved DFS compared with no adjuvant therapy (27% vs. 15%, p = 0.004). Despite competing risks for this elderly population, OS was also improved but the result was not statistically significant (34% vs. 22%, p = 0.08). CONCLUSIONS: The overall results of these four trials indicate that the continuation of investigations on combined chemo-endocrine therapies is warranted. The prognosis of the patients, all node-positive, treated with the most effective adjuvant treatment is such that there is a large potential for improvement.

Aged↗
PubMed1994

Treatment of childhood acute lymphoblastic leukemia: results of Dana-Farber Cancer Institute/Children's Hospital Acute Lymphoblastic Leukemia Consortium Protocol 85-01.

PURPOSE: The goals of this treatment program were as follows: to improve event-free survival (EFS) rates for high-risk (HR) patients by increasing the intensity of induction treatment; to improve EFS rates for infants by adding a special postinduction intensification; to treat the CNS using cranial irradiation doses that were lower than in our historic control group; and to confirm our previously obtained good results for children with T-cell disease. PATIENTS AND METHODS: Two hundred twenty children with acute lymphoblastic leukemia (ALL) from all risk groups, including infants and patients with T-cell disease, were treated between 1985 and 1987 with multiagent chemotherapy and cranial irradiation. RESULTS: The 7-year EFS rate (+/- SE) for all 220 patients was 78% +/- 3% at a median follow-up duration of 6.2 years, 89% +/- 4% for the 82 patients classified as standard risk (SR), and 72% +/- 4% for the remaining 138 patients classified as HR and very high risk (VHR). Eleven infants had an EFS rate of 55% +/- 15% that might be attributable to treatment with high doses of methotrexate and cytarabine (ara-c). Twenty children with T-cell disease had an EFS rate of 70% +/- 10%. CNS leukemia relapse (isolated or combined with bone marrow) occurred in four of 82 SR patients who received 18 Gy of cranial irradiation and four of 138 HR and VHR patients who received 24 Gy. CONCLUSION: This protocol, which featured early intensive treatment including asparaginase, doxorubicin, and cranial irradiation, provided good long-term disease control for children with ALL.

Adolescent↗
PubMed1994

Parametric approaches to quality-adjusted survival analysis. International Breast Cancer Study Group.

We present a parametric methodology for performing quality-of-life-adjusted survival analysis using multivariate censored survival data. It represents a generalization of the nonparametric Q-TWiST method (Quality-adjusted Time without Symptoms and Toxicity). The event times correspond to transitions between states of health that differ in terms of quality of life. Each transition is governed by a competing risks model where the health states are the competing risks. Overall survival is the sum of the amount of time spent in each health state. The first step of the proposed methodology consists of defining a quality function that assigns a "score" to a life having given health state transitions. It is a composite measure of both quantity and quality of life. In general, the quality function assigns a small value to a short life with poor quality and a high value to a long life with good quality. In the second step, parametric survival models are fit to the data. This is done by repeatedly modeling the conditional cause-specific hazard functions given the previous transitions. Covariates are incorporated by accelerated failure time regression, and the model parameters are estimated by maximum likelihood. Lastly, the modeling results are used to estimate the expectation of quality functions. Standard errors and confidence intervals are computed using the bootstrap and delta methods. The results are useful for simultaneously evaluating treatments in terms of quantity and quality of life. To demonstrate the proposed methods, we perform an analysis of data from the International Breast Cancer Study Group Trial V, which compared short-duration chemotherapy versus long-duration chemotherapy in the treatment of node-positive breast cancer. The events studied are: (1) the end of treatment toxicity, (2) disease recurrence, and (3) overall survival.

Breast Neoplasms↗
PubMed1993

Central nervous system treatment in childhood acute lymphoblastic leukemia. Long-term follow-up of patients diagnosed between 1973 and 1985.

BACKGROUND: Despite advances in the treatment of childhood acute lymphoblastic leukemia (ALL), optimal therapy of the central nervous system (CNS) remains controversial. METHODS: Between 1973 and 1985, 540 children with ALL (199 standard risk and 341 high risk) were treated on four protocols. RESULTS: The 7-year event-free survival rate (+/- standard error) was 62.1% (+/- 2.1) for the entire group: 71.8% (+/- 3.2) for standard-risk and 56.4% (+/- 2.7) for high-risk patients. Five hundred eighteen of the children entered complete remission and received cranial irradiation with intrathecal methotrexate for CNS treatment; 197 had standard-risk ALL and 321 had high-risk ALL. Thirty-one patients (5 standard risk and 26 high risk) had a CNS relapse with or without concurrent bone marrow relapse as an initial event, the latest of which was observed 49 months after complete remission. The cumulative incidence of CNS relapse was 6.0% (+/- 1.1) for the entire group: 2.5% (+/- 1.1) for standard-risk and 8.2% (+/- 1.5) for high-risk patients (P = 0.01). CNS recurrence of leukemia, whether as an "isolated" site or a "combined" site of relapse, was a major adverse event. Only 4 of 31 patients were alive for 25+, 28+, 54+, and 71+ months after a CNS relapse. The median survival time after CNS relapse was 22 months: 21 months for the 20 patients who had an isolated CNS relapse, and 23 months for the 11 patients who had a CNS relapse concurrent with a recurrence in other sites. CONCLUSIONS: Although attempts to diminish CNS treatment-related morbidity are warranted for standard-risk patients, the authors recommend that intensive CNS treatment be enhanced for the high-risk patients because CNS relapses continue to occur in this population. Furthermore, CNS relapse after cranial irradiation was associated with a very poor prognosis and needs to be treated as intensively as a bone marrow relapse.

Brain Neoplasms↗
PubMed1993

Sex differences in risk of second malignant tumours after Hodgkin's disease in childhood.

There have been reports of a high incidence of second malignant disorders in survivors of Hodgkin's disease. We studied the cumulative incidence of second tumours in 191 children, who were 16 years or younger at diagnosis, with stage IA-IVB Hodgkin's disease, treated at the Joint Center for Radiation Therapy, Boston, between 1969 and 1988. The 10-year actuarial survival was 89 (SE 2)%. The median follow-up time was 11 (range 3-21) years from diagnosis. 109 children were initially treated with radiotherapy alone, 61 received chemotherapy and radiotherapy, and 21 received chemotherapy alone. Second tumours arose in 15 patients 6-20 years after the diagnosis of Hodgkin's disease. The estimated cumulative incidence of second malignant disorders at 15 years was 12 (4)% overall. 10 of the second tumours arose among 66 female patients, compared with 5 among 125 male patients (cumulative incidence 24 [9] vs 5 [3]%). The relative risk of a second tumour for female compared with male patients was 4.5 (95% CI 1.4-15.1; p = 0.013). For male patients, the observed incidence of second tumours was 18 times that expected for the normal population (95% CI 6-42), whereas for female patients it was 57 times that expected (27-105). 13 of the second malignant disorders were solid tumours, including 4 breast cancers. Thus, the risk of a child treated for Hodgkin's disease developing a second tumour is higher for girls than for boys. The cumulative incidence of second cancers increases from 10 years after treatment. These findings emphasise the importance of continued surveillance in patients treated for Hodgkin's disease.

Adolescent↗
PubMed1993

Cox regression models for quality adjusted survival analysis.

We develop a method for incorporating covariates as regressors in a quality adjusted survival analysis (Q-TWiST) using Cox's proportional hazards model. The standard Q-TWiST method assumes that patients progress through a series of health states which differ in quality of life. The Kaplan-Meier product limit method is used to estimate the mean duration of each state by estimating the survival curves for the health state transition times. These estimates provide the basis for quality adjusted survival analysis. In this paper, the survival curves are modelled using Cox's proportional hazards regression. Quality adjusted survival is estimated given sets of covariate values, allowing one to profile patients. The results are useful for investigating how prognostic factors affect treatment benefits in terms of quality of life. We give a brief review of the standard Q-TWiST method and illustrate the extended methodology with an example from the International Breast Cancer Study Group Trial V comparing short duration versus long duration chemotherapy in the treatment of node-positive breast cancer.

Antineoplastic Agents↗
PubMed1993

Autologous bone marrow transplantation after a long first remission for children with recurrent acute lymphoblastic leukemia.

Fifty-one children with acute lymphoblastic leukemia (ALL) in second or subsequent remission after a first remission of at least 24 months underwent purged, autologous bone marrow transplantation (ABMT). Bone marrow was harvested in remission and purged in vitro with monoclonal antibodies specific for leukemia-associated antigens. Ablative chemotherapy included cytarabine, teniposide, and cyclophosphamide followed by total body irradiation. Of the 51 patients treated between November 1980 and June 1991, 5 died of treatment-related complications, 18 relapsed, 1 died of a second tumor at 6.7 years, and 27 remained in continuous complete remission for a median of 39 months (range, 9+ to 124+). Event-free survival (EFS) (+/- SE) at 3 years after ABMT was 53% +/- 7%. Leukemia-free survival (LFS) was 58% +/- 8%. In multivariate analysis, the most significant predictors of EFS were duration of longest pre-ABMT remission and remission duration immediately before ABMT. For LFS, the most significant predictors were cell dose per kilogram of marrow reinfused and duration of longest pre-ABMT remission. We conclude that ABMT for this population is an effective therapy available to the majority of children with relapsed ALL.

Adolescent↗
PubMed1993

Parametric extrapolation of survival estimates with applications to quality of life evaluation of treatments. International Breast Cancer Study Group.

Using parametric models, a procedure for projecting survival estimates beyond the follow-up limits of a clinical trial is developed. The methodology consists of fitting an appropriate parametric model to the tail of a survival curve and using the estimated model in conjunction with the Kaplan-Meier product-limit estimate to produce a composite survival-function estimator. This estimator is especially useful whenever a parametric model is more easily fit to the tail rather than to the entire survival curve. Probability plots are used to evaluate different parametric models as well as to determine appropriate values for the cut points that define the survival-function tail. The bootstrap method provides estimates of variation in the projected survival curve. The resulting projected survival estimates allow one to make inferences on long-term treatment effects in clinical trials. As a motivating application, we project survival curves to estimate long-term treatment effects on quality-of-life-adjusted survival. This represents an extension of a statistical procedure called Q-TWiST (Quality-adjusted Time Without Symptoms of disease and Toxicity of treatment), which evaluates treatments in terms of both quantity and quality of life. In a standard Q-TWiST analysis, the average time spent in each of a number of health states, which differ in quality of life, is estimated from clinical trial data. The health states are weighted according to the quality of life experienced, and the results are combined to produce an estimate of quality-adjusted survival. Such estimates, however, are restricted to the follow-up limit of the data. The way in which the extrapolation methodology provides longer range estimates of Q-TWiST is described. To illustrate the techniques, we apply the methodology to data from the International Breast Cancer Study Group Trial V, which compares long-duration adjuvant chemotherapy versus short-duration chemotherapy in the treatment of node-positive breast cancer. Five-year median follow-up data are used to predict 10-year results in terms of mean survival and mean Q-TWiST. The results indicate that patients continue to benefit greatly from the long-duration chemotherapy between 5 and 10 years following treatment.

Antineoplastic Agents↗
PubMed1993

Evaluation of effectiveness: Q-TWiST. The International Breast Cancer Study Group.

The effectiveness of cancer treatments is often expressed in terms of disease-free survival or overall survival relative risk reduction or odds ratios, and the quality of life effects are often assessed separately from survival. Such end points and summary measures may be inadequate, however, for comparing two treatments in terms of their palliative effects because there is a trade-off between treatment toxicity and increased disease-free interval. Furthermore, this trade-off may depend on individual patient preferences and prognostic situations. The goal of this paper is to describe a method for evaluating the effectiveness of cancer treatments in terms of palliation by simultaneously considering both quality and quantity of time following treatment so that therapeutic choice may be determined according to patient preferences on quality of life and prognostic situation. The method we present is an extension of the Quality-adjusted Time Without Symptoms and Toxicity (Q-TWiST) method for comparing treatment effectiveness in clinical trials of adjuvant therapies. We illustrate an application using data from the International Breast Cancer Study Group Trial V which compares two chemotherapy schedules with different toxicities.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

Prognostic factors in medulloblastoma, including DNA ploidy.

PURPOSE: DNA ploidy status, completeness of surgical resection, use of chemotherapy, adequacy of radiation therapy, metastatic stage, sex, and age at diagnosis were evaluated as predictors of relapse in 58 patients with cerebellar medulloblastoma. METHODS: Flow cytometry (FCM) and/or image analysis (IA) were used to characterize tumor DNA ploidy. Twelve tumors (21%) were found to be aneuploid, 11 (19%) tetraploid, and 35 (60%) diploid. RESULTS: The most significant predictors of relapse in univariate analyses were the adequacy of radiation (> or = 50 Gy) (P = .02), metastatic staging (P = .05), completeness of resection (P = .085), and DNA ploidy status (diploid/tetraploid v aneuploid; P = .11). When the 52 patients who received > or = 50 Gy were included in a multivariate Cox model analysis, those with diploid/tetraploid tumors had fewer recurrences than those with aneuploid tumors (relative risk, 0.33; 95% confidence interval, 0.12 to 0.89; P = .03). Patients with complete resections (P = .07), or with stage M0 disease (P = .06) had fewer recurrences than other patients, but these factors were not independent predictors of outcome. DNA ploidy status was correlated with age; 10 of the 12 aneuploid tumors were found in children ages 3 to 10 years. Age, sex, and the use of chemotherapy were not prognostically significant in these analyses. CONCLUSION: The adequacy of radiation dose and DNA ploidy were the most important prognostic factors in this series. Contrary to previous reports, when corrected for adequacy of treatment, DNA aneuploidy was associated with a poor outcome. By multivariate analyses, DNA ploidy was an independent variable, even when controlling for extent of surgical resection and metastatic stage.

Aneuploidy↗
PubMed1993

Pediatric histiocytosis. Characterization, prognosis, and oral involvement.

PURPOSE: Forty-five children with histiocytosis were reviewed to characterize such a group and to establish the prevalence of oral involvement. In addition, patients with and without oral disease were compared for severity of disease, response to treatment, and incidence of recurrent disease. PATIENTS AND METHODS: There were more boys (62.2%) than girls (37.8%) among the patients studied. About half (53.3%) were < 2 years of age. Approximately half of all patients had two or fewer affected organ systems at diagnosis. The average length of treatment was 46 weeks. RESULTS: A total 75.6% of patients were alive without disease at the completion of data collection, 15.6% died from the disease, 4.4% were alive with active disease, and 4.4% were alive with unknown status. Of the patients, 55.6% had long-term sequelae, and oral sequelae were present in 22.2% of the sample. In all, 28.8% of the patients exhibited oral symptoms at diagnosis, while 44.4% had oral involvement at some point during the course of the disease. Patients with oral symptoms were treated significantly longer and had more systemic therapy when compared with those without oral disease.

Child, Preschool↗
PubMed1992

Incidence of secondary acute myelogenous leukemia after treatment of childhood acute lymphoblastic leukemia.

BACKGROUND: Recent reports of secondary acute myelogenous leukemia (AML) occurring in children previously treated for acute lymphoblastic leukemia (ALL) prompted a review of patients with ALL treated at the Dana Farber Cancer Institute consortium (DFCI) between 1973 and 1987. Seven hundred fifty-two of 779 children treated for ALL entered complete remission. The mean follow-up time for the 752 patients was 4.4 years. Two children had AML develop 12 and 13 months after the diagnosis of ALL, respectively. METHODS: The estimated overall risk of secondary AML was calculated for the patient population as instances per 1000 patient-years of follow-up. This was compared with recent reported cases from another institution. RESULTS: The estimated overall risk of secondary AML was 0.61 instances per 1000 patient-years of follow-up (95% confidence interval: 0.15, 4.4). The difference between the risk of 0.61 among DFCI patients versus previously reported risk of 5.8 among a differently treated group of patients with ALL was statistically significant (P = 0.0008). No epipodophyllotoxin was used in the patients in the DFCI consortium. In contrast, an epipodophyllotoxin was used in 12 of 13 previously reported patients who had secondary AML develop. CONCLUSIONS: The authors concluded that the use of epipodophyllotoxins may be associated with an increased risk of having secondary AML develop in patients with ALL.

Adolescent↗