Research triangulation to derive meaning-based quality-of-life theory: adolescent resilience model and instrument development.

We describe the triangulation of qualitative and quantitative research methods used to develop and test the Adolescent Resilience Model (ARM). The differences in meaning-based and function-based health-related quality of life (HRQL) are discussed, and method triangulation is presented as a means of developing models of HRQL that represent the perspectives of the adolescent and family. Qualitative methods of phenomenology, simultaneous concept analysis, focus groups and thematic analysis were used to generate the ARM. Quantitative instrumentation and structural equation model development and testing were used to evaluate the ARM. A decision-making process for combining qualitative and quantitative research, so that both approaches are equally valued and used, is also presented. Int. J. Cancer Suppl. 12:125-131, 1999.

What caused my child's cancer? Parents' responses to an epidemiology study of childhood cancer.

When a child is diagnosed with cancer, parents try to understand why the cancer developed. Although usually it is not possible to explain what caused an individual child's cancer, clinical experience has shown that parents do form theories about the origins of their child's illness although, or perhaps because, no one knows the actual cause. A parent-completed epidemiology questionnaire (EQ), designed to provide a comprehensive and general epidemiology data base for studies conducted by the Childrens Cancer Group, included an open-ended item ("Do you have any additional comments or concerns about anything that could have caused or contributed to your child's illness?"). A convenience sample of 500 EQs containing responses to the open-ended question was reviewed independently by two experienced pediatric oncology nurses. Statements contained in the responses were categorized into 12 major themes according to content: concern about environmental exposures (n = 303), concern about family health history (n = 270), specific causality attribution (n = 39), puzzlement (n = 24), concern with cancer "clusters" (n = 23), concern with stress (n = 22), altruism (n = 15), specific feedback requests (n = 11), myths/misconceptions (n = 5), advocation of preventive education/screening (n = 4), active information-seeking (n = 6), and parental self-blame (n = 4). These themes or concerns provide useful information that can be applied in planning educational and supportive clinical interventions, as well as further research.

Wilms' tumor: a paradigm, a parallel, and a puzzle.

Wilms' tumor, a childhood tumor of the kidney, parallels retinoblastoma in several ways. Both malignancies occur in the very young, involve paired organs, arise from embryonal cells, can develop unilaterally or bilaterally, and can occur in hereditary and non-hereditary forms. However, Wilms' tumor rarely occurs in family clusters and may involve the loss of function of multiple genes.

A phase II study of diaziquone in children with recurrent or progressive primary brain tumors: a report from the Childrens Cancer Study Group.

Seventy-five children with recurrent, progressive or metastatic primary brain tumors were treated with aziridinylbenzoquinone (AZQ; Diaziquone) at 9 mg/m2/day by 30-minute intravenous infusion for five days every three weeks. Sixty-six patients were evaluable for response by imaging studies. There were five partial responses and one complete response for a combined response rate of 9%. A complete response lasting for 35+ months occurred in one of twelve patients with metastatic or locally recurrent ependymoma. Objective responses were also seen in patients with primitive neuroectodermal tumors (PNET) (1/8), low-grade glioma (1/6), and primary central nervous system lymphoma (1/1). Stable disease of greater than six months duration was seen in patients with ependymoma, PNET and medulloblastoma. Profound and prolonged myelo-suppression was the significant toxicity observed. As administered in this study, AZQ has marginal activity and severe toxicity.

A phase II study of diaziquone in children with recurrent or progressive solid tumors. Report from the Childrens Cancer Study Group.

Seventy-two children with recurrent, progressive, or metastatic lymphomas and other solid tumors, exclusive of primary central nervous system (CNS) tumors, were treated with aziridinylbenzoquinone (AZQ, diaziquone) at 9 mg/m2/day by 30-min intravenous infusion for 5 days every 3 weeks. Fifty-four patients were evaluable for response. Three partial responses occurred, two in patients with recurrent Hodgkin's disease and one in a patient with intraocular retinoblastoma. Sufficient numbers of patients with osteosarcoma, neuroblastoma, and Wilms' tumor were evaluable to demonstrate inactivity of this dosing regimen in these tumor types. Numbers of evaluable patients for other tumor types were insufficient to conclusively demonstrate inactivity. Myelosuppression, which was profound and prolonged, was observed. As administered in this study, AZQ has marginal activity and severe myelotoxicity in children with solid tumors.

A phase II study of diaziquone in childhood leukemia: a report from the Children's Cancer Study Group.

Diaziquone (aziridinylbenzoquinone, AZQ) was given by 30-min infusion at 25 mg/m2/day on a daily x 5 schedule to 16 children with acute lymphoblastic leukemia (ALL) in bone marrow relapse, 16 children with acute nonlymphocytic leukemia (ANLL) in bone marrow relapse, and 1 child with chronic myelocytic leukemia in blast crisis. None of the children achieved bone marrow remission. Five children (four with ALL and one with ANLL) were also evaluable for the response of central nervous system leukemia; all had a significant reduction in the cerebrospinal fluid blast count. Mild transient transaminase elevation was commonly seen. Grade 3 and 4 hyperbilirubinemia was seen in association with sepsis. AZQ was ineffective for induction of bone marrow remission as utilized in this study.

Phase I clinical evaluation of diaziquone in childhood cancer.

Diaziquone (AZQ), a new lipid-soluble antitumor agent, was given by 15-30-minute infusion on a daily X 5 schedule to 47 children with refractory solid tumors and leukemia. The starting daily dose of 6 mg/m2 was escalated to 10 and 35 mg/m2 in patients with solid tumors and leukemia, respectively. In patients with solid tumors, myelosuppression was dose-limiting at a daily dose of 10 mg/m2. In patients with leukemia, prolonged pancytopenia and bone marrow hypoplasia were observed at daily doses greater than or equal to 25 mg/m2. At these higher doses, significant hyperbilirubinemia associated with sepsis was also seen. Corresponding increases of transaminases or alkaline phosphatase and significant hemolysis were not noted. The maximum tolerated dose for this daily dose schedule was 9 mg/m2 in children with solid tumors and 25 mg/m2 in children with relapsed leukemia. Responses to AZQ included stabilization of disease in osteosarcoma, neurofibrosarcoma, pinealoma, and ependymoma. A patient with juvenile chronic myelocytic leukemia in blast crisis converted back to the chronic phase. A patient with acute lymphoblastic leukemia had a substantial decrease in cerebrospinal fluid blast count. Bone marrow aplasia was achieved in children with acute lymphoblastic leukemia and acute nonlymphoblastic leukemia; however, remissions were not achieved. A phase II study of AZQ in children with refractory malignancies is now being performed by the Childrens Cancer Study Group.