John M. Falletta

Bacteremia in sickle hemoglobinopathies

We analyzed 178 episodes of bacteremia that occurred during 13,771 patient-years of follow-up of 3451 patients with sickle hemoglobinopathies. Age-specific incidence rates of bacteremia were calculated for patients with sickle cell anemia (SS) and sickle cell-hemoglobin C (SC) disease. The incidence rate was highest among children with SS and SC younger than age 2 years. Children with SC showed an abrupt decrease after age 2 years, whereas children with SS had a gradual decline in rate from 2 to 6 years of age. The predominant pathogen in patients younger than 6 years was Streptococcus pneumoniae (66%); gram-negative organisms were responsible for 50% of bacteremias in patients 6 years and older. Urinary tract infection was present during 73% of Escherichia coli bacteremias, and 77% of Salmonella bacteremias were associated with osteomyelitis. In contrast, no focus of infection was present in 52% of pneumococcal bacteremias. The incidence of pneumococcal bacteremia in children with SS younger than age 3 years was 6.1 events/100 patient-years; the case fatality rate for pneumococcal sepsis in this age group was 24%. No hematologic or demographic variables were associated with occurrence of pneumococcal bacteremia in young children. Retrospective analysis of pneumococcal bacteremia suggests that the prophylactic use of penicillin may decrease the incidence in children younger than 3 years of age.

Treatment of children with progressive or recurrent brain tumors with carboplatin or iproplatin: a Pediatric Oncology Group randomized phase II study.

PURPOSE The Pediatric Oncology Group (POG) conducted a randomized phase II study to evaluate the activity of carboplatin and iproplatin in children with progressive or recurrent brain tumors. PATIENTS AND METHODS The study was designed to evaluate the activity of these agents and to compare the toxicities associated with their use. Treatment consisted of carboplatin 560 mg/m2 at 4-week intervals or iproplatin 270 mg/m2 at 3-week intervals. RESULTS The major toxicity observed was myelosuppression, particularly thrombocytopenia, for both agents. Ototoxicity (grade 1 or 2) was seen in 2.5% of patients treated with carboplatin and 1.3% of patients treated with iproplatin. The majority of patients with low-grade astrocytic neoplasms treated with carboplatin (nine of 12 patients) or iproplatin (eight of 12 patients) demonstrated tumor response or prolonged stable disease that persisted off-therapy. The duration of stable disease produced by carboplatin was particularly striking, ranging from 2 months to 68 + months (median, 40 + months). Neither drug demonstrated appreciable activity in the treatment of medulloblastoma (two of 26 responses to carboplatin, one of 14 responses to iproplatin), ependymoma (two of 17 responses to carboplatin, none of seven responses to iproplatin), high-grade glioma (two of 19 responses to carboplatin, one of 14 responses to iproplatin), or brain-stem tumors (one of 23 responses to carboplatin, none of 14 responses to iproplatin). CONCLUSION Carboplatin is active against low-grade gliomas. Further evaluation of the role of carboplatin in the preirradiation treatment of children with low-grade gliomas of the optic pathway is currently underway in a clinical trial.

Discontinuing penicillin prophylaxis in children with sickle cell anemia

OBJECTIVE To evaluate the consequences of discontinuing penicillin prophylaxis at 5 years of age in children with sickle cell anemia who had received prophylactic penicillin for much of their lives. DESIGN Randomized, double-blind, placebo-controlled trial. SETTING Eighteen teaching hospitals throughout the United States. PATIENTS Children with sickle cell anemia (hemoglobin SS or hemoglobin S beta 0-thalassemia) who had received prophylactic penicillin therapy for at least 2 years immediately before their fifth birthday and had received the 23-valent pneumococcal vaccine between 2 and 3 years of age and again at the time of randomization. Of 599 potential candidates, 400 were randomly selected and followed for an average of 3.2 years. INTERVENTIONS After randomization, patients received the study medication twice daily--either penicillin V potassium, 250 mg, or an identical placebo tablet. Patients were either seen in the clinic or contacted every 3 months thereafter for an interval history and dispensing of the study drug. A physical examination was scheduled every 6 months. MAIN OUTCOME MEASURES The primary end point was a comparison of the incidence of bacteremia or meningitis caused by Streptococcus pneumoniae in children continuing penicillin prophylaxis versus those receiving the placebo. RESULTS Six children had a systemic infection caused by S. pneumoniae, four in the placebo group (2.0%; 95% confidence interval 0.5%, 5.0%) and two in the continued penicillin prophylaxis group (1.0%; 95% confidence interval 0.1%, 3.6%) with a relative risk of 0.5 (95% confidence interval 0.1, 2.7). All invasive isolates were either serotype 6(A or B) or serotype 23F. Four of the isolates were penicillin susceptible, and two (one from each treatment group) were penicillin and multiply antibiotic resistant. Adverse effects of the study drug were reported for three patients (nausea, vomiting, or both), one of whom was in the placebo group. CONCLUSION Children with sickle cell anemia who have not had a prior severe pneumococcal infection or a splenectomy and are receiving comprehensive care may safely stop prophylactic penicillin therapy at 5 years of age. Parents must be aggressively counseled to seek medical attention for all febrile events in children with sickle cell anemia.

Regulatory and ethical considerations for linking clinical and administrative databases.

Clinical data registries are valuable tools that support evidence development, performance assessment, comparative effectiveness studies, and the adoption of new treatments into routine clinical practice. Although these registries do not have important information on long-term therapies or clinical events, administrative claims databases offer a potentially valuable complement. This article focuses on the regulatory and ethical considerations that arise from the use of registry data for research, including linkage of clinical and administrative data sets. (1) Are such activities primarily designed for quality assessment and improvement, research, or both, as this determines the appropriate ethical and regulatory standards? (2) Does the submission of data to a central registry, which may subsequently be linked to other data sources, require review by the institutional review board (IRB) of each participating organization? (3) What levels and mechanisms of IRB oversight are appropriate for the existence of a linked central data repository and the specific studies that may subsequently be developed using it? (4) Under what circumstances are waivers of informed consent and Health Insurance Portability and Accountability Act authorization required? (5) What are the requirements for a limited data set that would qualify a research activity as not involving human subjects and thus not subject to further IRB review? The approaches outlined in this article represent a local interpretation of the regulations in the context of several clinical data registry projects and focuses on a specific case study of the Society of Thoracic Surgeons National Database.

Efficacy of vincristine and cyclophosphamide in the therapy of recurrent medulloblastoma

We conducted a Phase II study of combination therapy with vincristine and cyclophosphamide in the treatment of patients with recurrent or metastatic medulloblastoma. Fourteen patients were treated with vincristine 2 mg/m2 (2.0-mg maximal dose) by intravenous bolus on Day 1 and cyclophosphamide 1 g/m2 by intravenous infusion on Days 1 and 2, with cycles repeated every 4 weeks. All 4 patients with extraneural disease (biopsy-proven bony metastases) responded (duration of responses 2+, 6+, 8, and 16+ months) and 4 of 8 evaluable patients with neuraxis disease responded (duration of response 2, 2+, 2+, and 21+ months). Toxicity was limited to neutropenia without any episodes of infection. These therapeutic results compare favorably with other reports of therapy for recurrent medulloblastoma and support the inclusion of vincristine and cyclophosphamide in randomized adjuvant therapy trials of patients with medulloblastoma.

Risk factors for Wilms tumor: Report from the national Wilms tumor study

Background. Previous epidemiologic studies have indicated that several factors may be associated with an increased risk of Wilms tumor including paternal occupational exposures, maternal exposure during pregnancy to cigarettes, coffee or tea, oral contraceptives, hormonal pregnancy tests, hair‐coloring products, maternal hypertension, vaginal infection during pregnancy, and higher birth weight of the child. The current study examines the nonoccupational risk factors using questionnaire data from a large national collaborative clinical trial.

POG 8625: A randomized trial comparing chemotherapy with chemoradiotherapy for children and adolescents with stages I, IIA, IIIA 1 Hodgkin disease: A report from the children's oncology group

To determine if 6 courses of chemotherapy alone could achieve the same or better outcome than 4 courses of chemotherapy followed by radiation therapy (chemoradiotherapy) in pediatric and adolescent patients with Hodgkin disease. Children ≤21 years old with biopsy-proven, pathologically staged I, IIA, or IIIA1 Hodgkin disease were randomly assigned 6 courses of alternating nitrogen mustard, oncovin, prednisone, and procarbazine/doxorubicin, bleomycin, vinblastine, and dacarbazine (treatment 1) or 4 courses of alternating nitrogen mustard, oncovin, prednisone, and procarbazine/doxorubicin, bleomycin, vinblastine, and dacarbazine +2550 cGy involved-field radiotherapy (treatment 2). The complete response rate was 89%, with a complete response and partial response rate of 99.4%. There was no statistically significant difference in event-free survival (EFS) or overall survival between arms. The EFS for those who achieved an early complete response was significantly higher than for those who did not. For pediatric patients with asymptomatic low-stage and intermediate-stage Hodgkin disease, chemotherapy and chemoradiotherapy both resulted in 3-year EFS of approximately 90% and statistically indistinguishable 8-year EFS and overall survival, without significant long-term toxicity. Early response to therapy was associated with higher EFS, a concept that has led to the Childrens Oncology Group paradigm of response-based risk-adapted therapy for pediatric Hodgkin disease.

Treatment of patients with recurrent primary brain tumors with AZQ

We have evaluated the efficacy of intravenous 2,5-diaziridinyl-3,6-biscarboethoxyamino-l,4-benzoquinone (diaziquone or AZQ, NSC-182986) in the treatment of recurrent primary anaplastic brain tumors. Three of 16 evaluable patients (18.8%) showed clinical and radiographic improvement that permitted discontinuation of corticosteroids, 4 patients (25%) showed either clinical or radiographic improvement and were considered partial responders, and 9 patients (56.2%) showed no effects after two courses of AZQ. The treatment was well tolerated, and hematologic toxicity was mild. Pharmacokinetic studies indicated rapid decay of the parent compound from plasma using two different infusion schedules. These results compare favorably with those obtained using the nitrosoureas or procarbazine as single agents.

Pediatric Oncology Group Utilization of Immunologic Markers in the Designation of Acute Lymphocytic Leukemia Subgroups: Influence on Treatment Responsea

The clinical application of blast cell immunophenotype testing is important in childhood ALL for the following reasons. (1) Knowledge of the immunologic group is important in predicting prognosis. Prognostic grouping may prove to be accomplished best by using a combination of traditional risk factors and immunologic phenotyping. However, definition of traditional risk factors may vary within the immunologic groups of ALL. (2) In assessing the relative effectiveness of different treatment regimens for children with ALL it is important to make comparisons among patients within the same major immunologic groups of ALL. (3) Identification of specific immunologic groups of patients within ALL may help in designing therapy for each group. The POG has already made preliminary attempts in this direction for T-ALL and B-ALL. However, leukemia species-specific therapy is still only a long-range goal. Laboratory research must endeavor to identify additional biologic characteristics peculiar to each major immunologic group of ALL. These characteristics may dictate therapeutic maneuvers in the future.

Multiple relapses of Clostridium difficile-associated diarrhea in a cancer patient. Successful control with long-term cholestyramine therapy.

Clostridium difficile-associated diarrhea (CDAD) is caused by a toxin elaborated by the anaerobic organism Clostridium difficile. Although the vast majority of CDAD cases are now associated with antibiotic use, the administration of antineoplastic agents alone can result in clinical manifestations. While therapy with oral vancomycin is usually successful, one quarter of patients will relapse. We describe a 16-year-old girl with osteogenic sarcoma whose therapy was significantly complicated by multiple relapses of CDAD. All resulted in hospital admission. She failed several standard therapies for relapsed CDAD and was cured only after prolonged cholestyramine therapy. A subset of multiply relapsed CDAD patients may require prolonged therapy with cholestyramine to control the disease.