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L L Robison

Publications and source records attributed to L L Robison.

At least 73 records · Page 4Linked to original sources
PubMed1997

Evaluation of parental participation in a case-control study of infant leukaemia.

This study was performed to evaluate participation rates and characteristics of participants in a case-control study of infant leukaemia. Eligible cases were identified throughout the United States, and two controls were selected for each case using a structured protocol for telephone random digit dialling. The non-participation rate, once a household agreed to provide an address to receive a letter explaining the study, was 7.9% for cases and 19.8% for controls. When comparing demographic differences between participants and non-participants, parents of eligible cases that participated were more likely than non-participating case parents to be white (P = 0.01) and to be currently married (P = 0.03); parents of eligible controls who participated were more likely than non-participating parents of eligible controls to have a higher education level (P < 0.01), more children under the age of 10 years (P = 0.05) and to be white (P < 0.01). These data have application for future studies involving infants with a serious disease and the use of random digit dialling for the selection of infant controls.

Case-Control Studies↗
PubMed1997

Magnetic field exposure assessment in a case-control study of childhood leukemia.

Epidemiologic evaluation of the relation between magnetic field exposures and cancer depends critically on study design, particularly the methods used for exposure assessment. We incorporated a complex magnetic field exposure assessment protocol into a large incident case-control study of childhood leukemia. We measured residential magnetic fields using a standard protocol in current and former homes of 638 cases and 620 controls and determined wire codes for 414 case-control pairs. We chose a time-weighted average of magnetic field measurements in each eligible home, weighted by the time the subject lived in each home as the main exposure metric for each subject. We found that 24-hour bedroom magnetic field measurements adequately characterize children's residential exposure and that measuring other rooms contributes only slightly to the estimate of average residential exposure to magnetic fields. Front door measured fields provide useful exposure information when interior measurements are missing. If feasible, measuring multiple homes in which the subject has resided is preferable to measuring a single home. A similar distribution of wire codes for controls agreeing or refusing to participate in our study implies that risk estimates derived from wire code data will not be influenced by response bias.

Adolescent↗
PubMed1997

Comparison of psychologic outcome in adult survivors of childhood acute lymphoblastic leukemia versus sibling controls: a cooperative Children's Cancer Group and National Institutes of Health study.

PURPOSE: To determine psychologic outcome, with the focus on emotional or mood state, of young adult survivors of childhood acute lymphoblastic leukemia (ALL) compared with sibling controls and to identify vulnerable subgroups at highest risk for negative mood. PATIENTS AND METHODS: Adult survivors (n = 580), aged > or = 18 years, who were treated before age 20 years on Children's Cancer Group (CCG) protocols for ALL and 396 sibling controls were administered a structured telephone interview and the Profile of Moods State (POMS), a standardized measure of affective state. RESULTS: Survivors had higher total mood scores (which indicates greater negative mood) than sibling controls (P<.01) and reported more tension (P< .01), depression (P<.01), anger (P<.01), and confusion (P<.01), but not more fatigue or less vigor. Female, minority, and unemployed survivors reported the highest total mood disturbance. Overall, survivors were more likely to be unemployed (P<.05) or working less than half-time (P<.01) compared with controls. CONCLUSION: This large, sibling-controlled, multisite study of young adult survivors of childhood ALL treated on CCG protocols after 1970 found significant increased negative mood in survivors, not accounted for by reported energy level differences, which suggests that these emotional effects are not likely the result of current illness. Survivors are less likely to be fully employed. Female, minority, and unemployed survivors are at greatest risk for emotional sequelae, a finding that indicates the need for targeted, preventive intervention.

Adult↗
PubMed1996

Trends in cancer incidence among children in the U.S.

BACKGROUND: This report provides results of an analysis of temporal trends in childhood cancer incidence in the U.S. stratfied by age, sex, and to a lessor extent, race, within common histologic subtypes. METHODS: Population-based data from nine registries of the Surveillance, Epidemiology, and End Results Program of the National Cancer Institute were analyzed. The analysis was limited to children age < or = 14 years. Cancer cases were restricted to those patients with a malignant neoplasm diagnosed between 1974 and 1991; more than 12,000 children were included. Average annual percentage change in incidence rates and corresponding 95% confidence intervals were estimated from the maximum likelihood method of Poisson regression. RESULTS: Among children age < or = 14 years there was a 1% average yearly increase (95% CI 0.6, 1.3) in the incidence rates of all malignant neoplasms combined. The average annual percentage change was similar for males and females, and slightly higher for black children compared with white children. Rates increased an average of 2% or more per year for astroglial tumors, rhabdomyosarcomas, germ cell tumors, and osteosarcomas. The average annual percentage change for acute lymphoid leukemia was 1.6% and trends were somewhat stronger for blacks than whites. Cancer trends, in general, were strongest in young children. In particular, increases in astroglial tumors and rhabdomyosarcomas were most apparent among children age < 3 years, and for retinoblastoma and neuroblastoma among children in their first year of life. The average annual percentage change for acute lymphoid leukemia did not vary dramatically with age, however children age < 2 years had stronger trends compared with older children. We found little evidence for increasing trends in Wilms' tumor, primitive neuroectodermal tumors, or hematopoietic neoplasms other than acute lymphoid leukemia. CONCLUSIONS: These results suggest that cancer occurrence among children within specific histologies increased modestly in the U.S. between 1974 and 1991, and that the increases were most apparent among young children.

Adolescent↗
PubMed1996

Birth defects in offspring of adult survivors of childhood acute lymphoblastic leukemia. A Childrens Cancer Group/National Institutes of Health Report.

BACKGROUND: It is not known if therapy for acute lymphoblastic leukemia (ALL) during childhood increases the risk of birth defects in the offspring of adult survivors. The Childrens Cancer Group (CCG), in collaboration with the National Institutes of Health (NIH), conducted a retrospective cohort study of adults successfully treated for childhood ALL to determine if their offspring had an increased incidence of birth defects compared with the offspring of their sibling controls. METHODS: Study subjects were patients who had been enrolled on CCG ALL protocols, who were treated for ALL prior to age 20, who survived at least 2 years, and who were at least age 18. Survivors (N=593) and sibling controls (N=409) were interviewed by telephone. RESULTS: The mean age of survivors was 22.6 years; the mean age of controls was 25.2 years. Among survivors, 93 (15.7%) had given birth to or fathered a total of 140 live-born offspring, (mean age, 3.4 years), and 122 (29.8%) sibling controls had given birth to or fathered a total of 228 live-born offspring (mean age, 5.9 years). There was no difference in the rate of birth defects between offspring of survivors and offspring of controls (3.6% [5 of 140] vs. 3.5% [8 of 228]; relative risk, 1.02; 95% confidence interval, 0.34, 3.05). No specific ALL therapy was associated with an increased rate of birth defects. Only female survivors reported offspring with birth defects (P=0.0735). CONCLUSIONS: Adult survivors of childhood ALL in our study were not at greater risk for having offspring with birth defects compared with sibling controls. Although this is the largest group of ALL survivors studied to date, the number of offspring is still not large enough to detect small but significant differences in rare events such as birth defects. Studies following this cohort into later adulthood and studies of additional ALL survivors are necessary to adequately quantify the risks.

Adult↗
PubMed1996

Malignant neoplasms following bone marrow transplantation.

We undertook an analysis of 2,150 recipients of bone marrow transplant (BMT) at the University of Minnesota to determine the incidence of post-BMT malignant neoplasms (MNs). Fifty-one patients developed 53 MNs, compared with 4.3 expected from general population rates (standardized incidence ratio [SIR], 11.6, 95% confidence interval [CI], 8.2-14.5). These included 22 occurrences of B-cell lymphoproliferative disorder (BLPD), 17 solid nonhematopoietic tumors, 10 myelodysplastic syndromes (MDS), 1 acute myelogenous leukemia (AML), 2 non-Hodgkin's lymphoma (NHL), and 1 Hodgkin's disease (HD). The estimated actuarial incidence of any post-BMT malignancy was 9.9% +/- 2.3% at 13 years posttransplant. The cumulative probability of BLPD plateaued at 1.6% +/- 0.3% by 4 years from transplant and factors independently associated with increased risk included in vitro T-cell depletion of marrow (relative risk (RR) = 11.9, P < .001), HLA mismatch (RR = 8.9, P < .001), use of antithymocyte globulin (ATG) for graft versus host disease (GVHD) prophylaxis (RR = 5.9, P < .001) or in the preparative regimen (RR = 3.1, P = .03) and primary immunodeficiency (RR = 2.5, P = .06). The cumulative probability of developing solid malignancy was 5.6% +/- 2.2% at 13 years from BMT. Malignant melanomas were the most common (SIR, 10.3, 95% CI 1.9 to 25.4). The actuarial incidence of MDS/AML plateaued at 2.1% +/- 0.8% at 9 years and was seen most often in older patients receiving autologous peripheral blood stem cells for HD or NHL. These data document that BMT recipients are at an increased risk of later malignancy, which may add significant morbidity and mortality to the transplant process. Methods for screening and identification of individuals at increased risk need to be addressed in future studies.

Adolescent↗
PubMed1996

Breast cancer and other second neoplasms after childhood Hodgkin's disease.

BACKGROUND: Patients who survive Hodgkin's disease are at increased risk for second neoplasms. As survival times increase, solid tumors are emerging as a serious long-term complication. METHODS: The Late Effects Study Group followed a cohort of 1380 children with Hodgkin's disease to determine the incidence of second neoplasms and the risk factors associated with them. RESULTS: In this cohort, there were 88 second neoplasms as compared with 4.4 expected in the general population (standardized incidence ratio, 18.1; 95 percent confidence interval, 14.3 to 22.3). The estimated actuarial incidence of any second neoplasm 15 years after the diagnosis of Hodgkin's disease was 7.0 percent (95 percent confidence interval, 5.2 to 8.8 percent); the incidence of solid tumors was 3.9 percent (95 percent confidence interval, 2.3 to 5.5 percent). Breast cancer was the most common solid tumor (standardized incidence ratio 75.3; 95 percent confidence interval, 44.9 to 118.4), with an estimated actuarial incidence in women that approached 35 percent (95 percent confidence interval, 17.4 to 52.6 percent) by 40 years of age. Older age (10 to 16 vs. <10 years) at the time of radiation treatment (relative risk, 1.9) and a higher dose (2000 to 4000 vs. <2000 cGy) of radiation (relative risk, 5.9) were associated with significantly increased risk of breast cancer. The estimated actuarial incidence of leukemia reached a plateau of 2.8 percent (95 percent confidence interval, 0.8 to 4.8 percent) 14 years after diagnosis. Treatment with alkylating agents, older age at the diagnosis of Hodgkin's disease, recurrence of Hodgkin's disease, and a late stage of disease at diagnosis were risk factors for leukemia. CONCLUSIONS: The risk of solid tumors, especially breast cancer, is high among women who were treated with radiation for childhood Hodgkin's disease. Systematic screening for breast cancer could be important in the health care of such women.

Actuarial Analysis↗
PubMed1996

Parental alcohol consumption, cigarette smoking, and risk of infant leukemia: a Childrens Cancer Group study.

BACKGROUND: Whether parental drinking and smoking during pregnancy are associated with an increased risk of cancer in offspring is controversial. There are some indications that maternal alcohol consumption is associated with an elevated risk of acute myeloid leukemia (AML) appearing in very young children. Evidence for an association between maternal smoking during pregnancy and risk of leukemia in offspring has been inconsistent. PURPOSE: Using data from a Children's Cancer Group case-control study, we evaluated relationships between infant leukemia risk and parental alcohol consumption and/or cigarette smoking during pregnancy or during the month prior to it. METHODS: Three hundred two leukemia cases (203 acute lymphoid leukemias [ALLs], 88 AMLs, and 11 other leukemia types) diagnosed in children at 18 months of age or younger and 558 individually matched, regional (i.e., same telephone area code and exchange number) controls were included in the analysis. Information concerning parental alcohol consumption and smoking behavior during the index pregnancy and during the month prior to it was collected by telephone interviews with the mothers of all case and control subjects and the fathers of 250 case and 361 control subjects. Odds ratios (ORs) were used to measure the risk of infant leukemia associated with parental smoking and drinking; tests for trend were used to assess dose-response relationships. The data were analyzed further after stratifying the leukemia cases according to histologic and morphologic types. Reported P values are from two-sided tests of statistical significance. RESULTS: Maternal drinking during pregnancy (compared with not drinking) was associated with ORs of 1.43 (95%) confidence interval [CI] = 1.00-2.04) for ALL and 2.64 (95% CI = 1.36-5.06) for AML. A dose-response relationship was observed for total maternal alcohol consumption during pregnancy and risk of AML (P < .01). Alcohol-related risk appeared to be most pronounced for children who developed AML with a morphology of M1 (myeloblastic with minimal maturation) or M2 (myeloblastic with maturation (OR = 7.62; 95% CI = 2.03-28.64). Paternal alcohol consumption did not confer an increased risk of infant leukemia. Maternal smoking during pregnancy (compared with not smoking) was negatively associated with infant leukemia risk (OR = 0.66 and 95% CI = 0.46-0.94 for total leukemia; OR = 0.45 and 95% CI = 0.21-0.96 for AML), whereas paternal smoking 1 month prior to pregnancy (compared with not smoking during the same period) was related to an elevated risk of ALL (OR = 1.56; 95% CI = 1.03-2.36). CONCLUSIONS: Maternal alcohol consumption during pregnancy increases the risk of infant leukemia, especially AML. Maternal smoking, however, does not elevate risk for either AML or ALL. IMPLICATIONS: The data suggest that in utero exposure to alcohol may contribute to leukemogenesis involving myeloid cells.

Adult↗
PubMed1996

Childhood cancer in the United States. A geographical analysis of cases from the Pediatric Cooperative Clinical Trials groups.

BACKGROUND: After injuries, cancer is the leading cause of death in children younger than 15 years in the United States. Despite dramatic increases in 5-year survival rates, more than 100,000 person-years of life are lost to childhood cancer each year. The exact proportion of pediatric cancer patients who receive care at centers that utilize up-to-date therapeutic protocols [such as those affiliated with the Childrens Cancer Group (CCG) or the Pediatric Oncology Group (POG)] remains unknown. The purpose of this study was to estimate the proportion and geographic distribution of childhood cancer patients in the United States who are seen at participating centers of the CCG and the POG. METHODS: Patients included 21,026 incident pediatric cancer cases diagnosed from January 1, 1989 through December 31, 1991. Observed numbers of pediatric cancer cases were compared with expected numbers of cases calculated from incidence rates obtained from the Surveillance, Epidemiology, and End Results (SEER) Program and population counts obtained from the 1990 U.S. Census Bureau. RESULTS: Approximately 94% of children younger than 15 years diagnosed with cancer are seen at an institution that is a member of either POG or CCG. Comparisons of the observed-to-expected numbers of incident cases in the age groups (birth-4 years, 5-9 years, 10-14 years, and 15-19 years) demonstrated ascertainment rates of 100, 93, 84, and 21%, respectively. In some regions within the United States the observed number of cases was significantly less than that expected number, including areas of Idaho, Oklahoma, and Virginia. In addition, there were areas in which the observed number of childhood cancer cases was substantially greater than that expected, including areas in California and Florida. CONCLUSIONS: The membership of the cooperative clinical trials groups (the POG and CCG) ascertain and provide access to state-of-the-art treatment protocols for the vast majority of pediatric cancer patients in the country. For the younger age groups, the CCG and POG may represent a mechanism of case ascertainment that approximates a population-based series for the continental United States. Those areas that have large enough discrepancies in observed-to-expected numbers may warrant further investigation.

Adolescent↗
PubMed1996

Maternal exposure to potential inhibitors of DNA topoisomerase II and infant leukemia (United States): a report from the Children's Cancer Group.

Nearly 80 percent of infant leukemias present with an abnormality involving the MLL gene at 11q23. Moreover, secondary acute myeloid leukemias (AML) that occur as the result of chemotherapy agents, which are known to inhibit DNA topoisomerase II, often manifest the same MLL abnormalities. It has been hypothesized that de novo infant leukemias may occur as a result of maternal exposure to agents in diet and medications that inhibit DNA topoisomerase II. Three epidemiologic studies of childhood leukemia with similar methodologies were conducted in the United States and Canada over the past 10 years by the Children's Cancer Group (CCG). Of the total 771 mothers of infants diagnosed at one year of age or less (< 12.5 months) who originally were interviewed (303 infant cases and 468 matched controls) across the three studies, follow-up questionnaire data on maternal exposure to potential DNA topoisomerase II inhibitors during pregnancy were available on 84 cases and 97 matched controls in the US. For maternal diet, a composite variable was created that consisted of 10 foods identified alpha priori as containing DNA topoisomerase II inhibitors. There were no significant trends with increasing maternal consumption for either the overall group, or the acute lymphoblastic leukemia (ALL) stratum. However, within the AML stratum, there was a statistically significant positive association (P trend = 0.04) with increasing consumption of DNA topoisomerase II-inhibitor containing foods (odds ratio [OR] = 9.8, 95 percent confidence interval [CI] = 1.1-84.8; OR = 10.2, CI = 1.1-96.4; for medium and high consumption, respectively). Other potential topoisomerase II inhibitors were explored; no significant findings were found. Results of this preliminary study, in combination with molecular data, should be used in future investigations of childhood leukemia (particularly, infant) to justify the incorporation of a detailed dietary history.

Acute Disease↗
PubMed1996

Big babies and infant leukemia: a role for insulin-like growth factor-1?

Several epidemiologic studies have demonstrated that high birthweight is associated with an increased risk of infant leukemia; however, the reason for this relationship is unclear. Biologic data demonstrate that birth weight is correlated positively with circulating levels of insulin-like growth factor-1 (IGF-1). IGF-1 is important in blood formation and regulation and has been shown to stimulate the growth of both myeloid and lymphoid cells in culture. Since infants who develop leukemia are likely to have had at least one transforming event occur in utero, we hypothesize that high levels of IGF-1 may both produce a larger baby and contribute to leukemogenesis.

Birth Weight↗
PubMed1996

Methodologic issues in the study of second malignant neoplasms and pregnancy outcomes.

For future studies of late effects, it will be necessary for investigators to consider methodologic issues carefully as a means of insuring the quality of research in this increasingly important area. Recognizing the advantages and limitations in univariate and multivariate analyses will help in selecting the best analytic approach. There are many methods for denoting risk. Selection of the method will often be dependent on study design, but should also be the one believed most effective for communicating the study results. There is little question there is a need for well-designed studies for second malignancies, especially those designed to evaluate late-occurring second cancer (i.e., in the second, third, and fourth decade following treatment). With the aging of the childhood cancer survivor population, questions regarding pregnancy issues are increasing. These questions range from those relating to fertility to others associated with mutagenesis. When considering studies of these late effects, it is important to recognize the need for selecting the most appropriate study design and statistical methods.

Adolescent↗
PubMed1995

Incidence of cancer in children in the United States. Sex-, race-, and 1-year age-specific rates by histologic type.

BACKGROUND: Rates of cancer in children usually are presented in 5-year age groups, despite large variations of incidence within these groups. The purpose of this report is to provide histology-specific incidence rates within single-year age groups, stratified by sex and race, among children. METHODS: Data from the National Cancer Institute's SEER Program were used to calculate incidence rates among children younger than 15 years of age at diagnosis. The SEER population denominator file was modified to allow calculation of rates within single years of age. RESULTS: Large differences in rates within 5-year age groups were found for many histologic types. Retinoblastoma and Wilms' tumor, for instance, had up to eight-fold differences. Substantial differences also were observed for non-Hodgkin's lymphoma, neuroblastoma, Hodgkin's disease, acute lymphoid leukemia, acute myeloid leukemia, and osteosarcoma. In general, rates were higher among males than females, although female rates were often higher among young children. Rates of white children were generally higher than those of black children, especially during the first 5 years of life. Embryonal tumors comprised the majority of neoplasms during the first 2 years of life.

Adolescent↗
PubMed1995

History of maternal fetal loss and increased risk of childhood acute leukemia at an early age. A report from the Childrens Cancer Group.

BACKGROUND: Maternal reproductive history of fetal loss previously has been reported to be associated with an increased risk of leukemia in subsequent offspring. Data from a Childrens Cancer Group (CCG) case-control study were analyzed to test the hypothesis that this association was dependent on the number of previous fetal losses and age at leukemia diagnosis. METHODS: A case-control study using a large Childrens Cancer Group database examined maternal history of fetal loss as a risk factor for childhood leukemia in subsequent offspring. One thousand seven hundred fifty-three patients with childhood acute leukemia were compared with 839 community control subjects s and 2081 nonleukemia cancer control subjects. RESULTS: A modest increase in risk was found to be associated with a history of fetal loss. Stratification by age at diagnosis of leukemia showed that this association was significant only for those patients diagnosed before 4 years of age and most significant in those patients diagnosed before 2 years of age. When comparing community controls with patients acute lymphocytic leukemia diagnosed before 2 years of age, one previous fetal loss was associated with a five-fold increased risk (P < 0.001) whereas two or more fetal losses were associated with a relative risk of 24.8 (P < 0.001). Similarly, patients with acute myelocytic leukemia diagnosed before 2 years of age demonstrated 5-fold and 12-fold increased risks associated with the previous fetal loss and 2 or more previous fetal losses, respectively. CONCLUSIONS: Childhood acute leukemia occurring at younger ages may be associated with an underlying genetic abnormality or chronic environmental exposure, which can be either lethal to the developing fetus or mutagenic and result in the development of acute leukemia.

Abortion, Spontaneous↗
PubMed1995

Assessment of environmental and genetic factors in the etiology of childhood cancers: the Childrens Cancer Group epidemiology program.

The occurrence of cancer during childhood represents one of the leading causes of death within the pediatric and adolescent age group. It is estimated that approximately 8000 children will be diagnosed annually with cancer in the United States. Epidemiologic research addressing the etiology of childhood cancer has been limited because of the difficulties in identifying a sufficiently large study population. Moreover, the use of retrospectively ascertained childhood cancer cases in epidemiologic investigations has restricted the incorporation of biological and clinical parameters. The Childrens Cancer Group has developed an active program in epidemiologic research, with over a decade of experience demonstrating the feasibility and strengths of conducting analytic epidemiologic studies within a cooperative clinical trials network. The availability of detailed clinical and biologic data on cases diagnosed within the cooperative group facilitates the transfer of state-of-the-art technology to epidemiologic research.

Acute Disease↗
PubMed1995

Random-digit dialing for control selection in childhood cancer studies: the geographic proximity and demographics within matched sets.

The purpose of this analysis was to evaluate the degree of matching in 95 individually matched pairs from a case-control study of childhood leukemia that used random-digit dialing to select control subjects. Both geographic proximity (of each case subject to his or her matched control subject) and differences in socioeconomic status were evaluated. The median distance between matched pairs was 3.2 km. There were no significant differences in distance between matched pairs by urban/rural status and geographic location. For studies of childhood cancer drawn from pediatric referral centers, random-digit dialing appears to provide a suitable control group.

Case-Control Studies↗