Multiagent chemotherapy and deferred radiotherapy in infants with malignant brain tumors: a report from the Children's Cancer Group

PURPOSE

To evaluate response rate, event-free survival (EFS), and toxicity of two chemotherapeutic regimens for treatment of children younger than 36 months with malignant brain tumors and to estimate control intervals without irradiation in children with no residual tumor after initial surgery and induction chemotherapy and with delayed irradiation in patients with residual tumor or metastatic disease at diagnosis.

PATIENTS AND METHODS

Patients were randomly assigned to one of two regimens of induction chemotherapy (vincristine, cisplatin, cyclophosphamide, and etoposide v vincristine, carboplatin, ifosfamide, and etoposide). Maintenance chemotherapy began after induction in children without progressive disease. Children with no residual tumors after induction therapy and no metastatic disease at diagnosis were not to receive radiation therapy unless their tumors progressed.

RESULTS

Two hundred ninety-nine infants were enrolled. Forty-two percent of patients responded to induction chemotherapy. At 5 years from study entry, the EFS rate was 27% +/- 3%, and the survival rate was 43% +/- 3%. There was no significant difference between the two arms in terms of response rate or EFS. For medulloblastoma, supratentorial primitive neuroectodermal tumor, ependymoma, and rhabdoid tumors, 5-year EFS rates were 32% +/- 5%, 17% +/- 6%, and 32% +/- 6%, and 14% +/- 7%, respectively. Fifty-eight percent of patients who were alive 5 years after study entry had not received radiation therapy.

CONCLUSION

Intensified induction chemotherapy resulted in a high response rate of malignant brain tumors in infants. Survival was comparable to that of previous studies, and most patients who survived did not receive radiation therapy.

Flow cytometric immunophenotyping test for staging/monitoring neuroblastoma patients

Ten years ago, we made an incidental flow cytometric observation while immunophenotyping biopsy and marrow samples from children suspected to have leukemia/non-Hodgkin's lymphoma, but were subsequently diagnosed with neuroblastoma. The samples contained neoplastic CD45(-) cells that had an extremely bright CD56(+) (beyond the fourth decade on a four-decade scale) population distinguishable from CD45(+)CD56(usual density+) natural killer lymphocytes as well as other CD45(-)CD56(usual density+) nonhematopoietic tumors such as small cell carcinoma or melanoma. Following the "rare event" philosophy of selecting one negative and two positive antigens, we initially tried a "cocktail" of CD45(-)CD56(very bright+) neuron-specific enolase (NSE)(cytoplasmic+). We later modified the procedure to a more clinically applicable "lysed whole blood" CD45(-)CD56(very bright+) ganglioside GD2(+) cocktail to improve turnaround time (eliminating the cell permeabilization step for cytoplasmic NSE analysis), specificity, and sensitivity of the assay. A total of 123 marrow/tissue/fluid samples were analyzed by the various forms of the assay. Clearly interpretable samples had an 83% specificity and a 100% sensitivity. The three-color GD2 assay has successfully detected cells in marrow samples to a level of 0.002% (1 per 10(5) cells) using patient samples (not artificially "spiked" material). We added CD81 expression of the neuroblastoma cells as a fourth color and now use this rare event clinical test to help stage and monitor all patients with neuroblastoma.

Prevention of central venous catheter-related infections and thrombotic events in immunocompromised children by the use of vancomycin/ciprofloxacin/heparin flush solution: A randomized, multicenter, double-blind trial

PURPOSE

To determine whether an antibiotic flush solution containing vancomycin, heparin, and ciprofloxacin (VHC) can prevent the majority of line infections.

PATIENTS AND METHODS

A prospective double-blind study was performed comparing VHC to vancomycin and heparin (VH) to heparin alone in 126 pediatric oncology patients.

RESULTS

The 153 assessable lines resulted in 36,944 line days studied. There were 58 blood stream infections (43 gram-positive, 14 gram-negative, and one fungal). Forty were defined as line infections (31 heparin, three VH, six VHC). The time to develop a line infection was significantly increased using either antibiotic flush (VH, P =.011; VHC, P =.036). The rate of total line infections (VH, P =.004; VHC, P =.005), gram-positive line infections (VH, P =. 028; VHC, P =.022), and gram-negative line infections (VH, P =.006; VHC, P =.003) was significantly reduced by either VH or VHC. Sixty-two (41%) of the lines developed 119 occlusion episodes (heparin, 3.99 per 1,000 line days; VHC, 1.75 per 1,000 line days; P =.0005). Neither antibiotic could be detected after flushing, and no adverse events were detected, including increased incidence of vancomycin-resistant Enterococcus colonization or disease.

CONCLUSION

The use of either VH or VHC flush solution significantly decreased the complications associated with the use of tunneled central venous lines in immunocompromised children and would save significant health care resources.

Hepatoblastoma metastatic to brain: prolonged survival after multiple surgical resections of a solitary brain lesion

PURPOSE

Pulmonary metastases of hepatoblastoma confined to the lung have been cured using therapy that included radical surgical resection. We report the case of a child with a hepatoblastoma metastatic to brain that was successfully treated with multiple surgical resections, irradiation, and chemotherapy. The case demonstrates that such an approach, employing aggressive surgery, can produce durable remission of an extrapulmonary metastasis with hepatoblastoma.

PATIENTS AND METHODS

A 17-month-old girl presented with a hepatoblastoma that remained unresectable after chemotherapy and irradiation and underwent orthotopic liver transplantation 14 months after diagnosis. After twice undergoing surgical resections of pulmonary metastases 22 and 31 months from diagnosis, 1 month later (32 months from diagnosis), she developed a solitary metastatic right brain lesion that later recurred twice in the same location, 5 and 6 years from initial diagnosis. Each time she underwent surgical resection of the brain lesion and received local irradiation after the first two resections and chemotherapy after the third. At the last surgery, resection was continued until histologically negative tumor margins were obtained.

RESULTS

The child is currently without evidence of disease or neurological deficit 10.5 years from initial diagnosis.

CONCLUSION

The durable remission achieved after multiple resections of the recurrent solitary cerebral metastasis in this child demonstrates that an aggressive surgical approach to extrapulmonary metastases in such a setting can contribute to prolonged survival, just as has been shown with isolated metastatic pulmonary disease.

Pediatric midbrain tumors: a benign subgroup of brainstem gliomas

The presentation, radiographic findings and course of 17 children with MRI-documented intrinsic midbrain lesions are reviewed. The anatomic centers of all the lesions were tectal, peritectal, or tegmental. Lesions centered at the pineal gland were excluded. Signs of increased intracranial pressure from hydrocephalus requiring shunt placement were present in 14 patients. Histopathological diagnosis was confirmed in three tumors; these were low grade astrocytomas and all received focal irradiation, as did one unbiopsied tumor. The remaining 13 patients with no histopathological diagnosis received no therapy other than shunt placement in 11. All but one of the lesions have remained clinically and radiographically stable, with a 4-year progression-free and total survival of 94 and 100%, respectively. We conclude that mass lesions originating in the upper midbrain are a subset of intrinsic brainstem tumors with a relatively benign course, usually presenting with hydrocephalus after infancy. They may remain stable for considerable periods and may require no further therapy after treatment of hydrocephalus. Surgical biopsy and/or resection can usually be reserved for progressive or atypical lesions which may also require further adjuvant therapy.

Low level CD20 expression on T cell malignancies

Although initially thought to be a B lineage restricted antigen, low "density" or antibody binding capacity (ABC) CD20 has recently been detected on subset(s) of normal T lymphocytes (Hultin et al.: Cytometry 14:196-204, 1993). We report low ABC CD20 expression in three (two children, one adult) cases of T-acute lymphoblastic leukemia (T-ALL). CD20 and other pertinent antigens were detected using a direct dual color method with a Becton Dickinson FACScan flow cytometer and Simulset software. Only one cell population based on light scatter was noted in each case that immunophenotypically represented almost a pure population of malignant cells expressing T lymphocyte antigens (for example, CD7 98%, 92%, and 100%, respectively). A total of 95%, 87%, and 79% of the cells from the three cases expressed CD20 with an unusual low ABC compared to the customary "bright" CD20 expression on normal B lymphocytes. Other B lymphocyte associated antigens, such as CD19, CD22, Dr, and immunoglobulin light chains, were negative. Eleven other T lymphocytic malignancies from 1991 to 1993 were CD20 negative, including three other case of T-ALL (one adult and two children). One unusual case of intestinal small lymphocytic non-Hodgkin's lymphoma with a natural killer/T lymphocytic immunophenotype not described in this report appeared to be CD20"dim"+. Low ABC CD20 expression by T lymphocytic malignancies may provide a more unique immunophenotypic "fingerprint" to help support the diagnosis of T cell neoplasia vs. normal/reactive T cells (for example, low ABC CD20 cells represent only 2.4 +/- 1.5% of normal peripheral blood lymphocytes). This characteristic might also facilitate monitoring patients for residual or recurrent disease.(ABSTRACT TRUNCATED AT 250 WORDS)

Brief unconscious sedation for painful pediatric oncology procedures. Intravenous methohexital with appropriate monitoring is safe and effective

PURPOSE

We report here our experience in using intravenous methohexital (MHX), an ultrashort-acting barbiturate, for brief unconscious sedation of pediatric oncology outpatients undergoing painful, invasive procedures.

METHODS

Following published monitoring guidelines for deep pediatric sedation, 1.0 mg/kg MHX was administered immediately before the procedure, 1% xylocaine was given locally, and MHX was additionally titrated to maintain minimal response to pain during the procedure. Clinical data reported here were gathered retrospectively from permanent medical records.

RESULTS

Data reported here represent 132 evaluable consecutive procedures in 33 patients ranging in age from 1.6 to 20.5 years. Patients underwent an average of 4 +/- 3 procedures and received a mean total MHX dose per procedure of 5.8 +/- 2.1 mg/kg. The mean length of time from start of sedation to full arousability was 30 +/- 12 min. Twenty-three (17.4%) procedures were associated with clinically insignificant decreases in diastolic blood pressure or heart rate below resting normal ranges for age. Eight (6.1%) procedures in six patients were associated with minor complications requiring no intervention, such as transient behavioral changes, transient myoclonus, and minimal stridor. Five procedures (3.8%) in five patients required simple suctioning to manage secretions. Only two procedures (1.5%) in two patients required brief bag-mask ventilation plus suctioning for suspected laryngospasm. None required intubation. No differences in clinical features or MHX doses were noted for patients with, as compared to those without, complications. All procedures were completed with a satisfactory level of sedation.

CONCLUSIONS

Our experience indicates that MHX, with appropriate monitoring as described here, is a safe and effective agent for use in pediatric oncology outpatient sedation programs.

Clinical and biologic effects of granulocyte colony stimulating factor in the treatment of myelokathexis

Successful treatment of a patient with myelokathexis, a rare form of chronic neutropenia associated with recurrent infections, is described. Rapid mobilization of bone marrow neutrophils and improved myeloid morphologic features were observed after treatment with human granulocyte colony stimulating factor. Transient thrombocytopenia and bone pain were observed during treatment. Although neutrophil chemotaxis, superoxide production, and FcRIII surface expression were reduced, the patient improved clinically after restoration of a normal neutrophil count.

Exposure of human neutrophils to exogenous nucleotides causes elevation in intracellular calcium, transmembrane calcium fluxes, and an alteration of a cytosolic factor resulting in enhanced superoxide production in response to FMLP and arachidonic acid

Exposure of human neutrophils to micromolar concentrations of both hydrolyzable and nonhydrolyzable purine nucleotides caused the generation of transient rises in intracellular calcium (Ca2+), Ca2+ fluxes across the membrane, and primed the cells for enhanced production of superoxide (O2-) when subsequently exposed to agonists such as FMLP and arachidonic acid. The neutrophils were most sensitive to adenosine triphosphate (ATP) and ATP-gamma-S, which produced Ca2+ transients and enhanced O2- production at concentrations as low as 1 to 5 mumol/L, with a doubling of O2- generation at 25 to 50 mumol/L. Adenosine diphosphate (ADP), guanosine triphosphate (GTP), and 5'-adenylylimidodiphosphate (AMP-PNP) required approximately 10-fold higher concentrations to cause similar effects. Adenosine did not cause Ca2+ fluxes or a Ca2+ transient and was inhibitory of O2- production. There was a strong correlation between a nucleotide's ability to generate a Ca2+ response and its ability to enhance O2- generation. Nitrogen cavitation and subcellular fractionation of the neutrophils after a brief exposure to ATP, ATP-gamma-S, and AMP-PNP revealed that the enhanced O2- generating capacity was stable and detectable in a cell-free assay system. By combining variously treated cytosolic and membrane fractions, it was found that the enhanced O2- production was attributable to a modification of a component(s) of the cytosol.

Stimulation of human neutrophil adhesive properties by adenine nucleotides

Inasmuch as adenine nucleotides may be secreted by platelets during inflammation, we sought to determine whether ATP and related compounds could serve as stimuli of neutrophil (polymorphonuclear cells, PMN) activation as manifested by an increase in their adhesive properties. Exposure of isolated human PMN to ATP or its nonhydrolyzable analog, adenosine 5'-O-(3-thiotriphosphate) did indeed stimulate an increase in cellular adhesive function as assessed by an increase in the surface expression of the leukocyte adhesion-promoting glycoprotein, Mo1 (CD11b/CD18), the initiation of PMN aggregation, and (in the case of ATP) the attachment of increased numbers of albumin-coated polystyrene latex beads. However, this increase in PMN adhesive function was not accompanied by the generation of products of the respiratory burst. These in vitro data suggest the possible influence of secreted adenine nucleotides in promoting neutrophil adhesion-dependent interactions at inflammatory sites in vivo.

Stimulation of human neutrophil adhesive properties by adenine nucleotides

Inasmuch as adenine nucleotides may be secreted by platelets during inflammation, we sought to determine whether ATP and related compounds could serve as stimuli of neutrophil (polymorphonuclear cells, PMN) activation as manifested by an increase in their adhesive properties. Exposure of isolated human PMN to ATP or its nonhydrolyzable analog, adenosine 5'-O-(3-thiotriphosphate) did indeed stimulate an increase in cellular adhesive function as assessed by an increase in the surface expression of the leukocyte adhesion-promoting glycoprotein, Mo1 (CD11b/CD18), the initiation of PMN aggregation, and (in the case of ATP) the attachment of increased numbers of albumin-coated polystyrene latex beads. However, this increase in PMN adhesive function was not accompanied by the generation of products of the respiratory burst. These in vitro data suggest the possible influence of secreted adenine nucleotides in promoting neutrophil adhesion-dependent interactions at inflammatory sites in vivo.

Clinical features and current management of chronic granulomatous disease

Chronic granulomatous disease (CGD) is a diverse disorder characterized by several clinical presentations and a multitude of metabolic defects. The authors summarize the clinical features and current management of CGD, offer a definition of the disease based on molecular defects of the respiratory burst, and present their experience with trimethoprim/sulfamethoxazole prophylaxis.

Evaluation of the patient with a possible phagocytic disorder

This article presents an outline of a rational approach to the patient with recurrent infections. The different categories of phagocytic defects are reviewed, and a brief discussion of the various tests of phagocyte function is presented.