[Ionizing radiation received by patients with osteosarcoma during intra-arterial chemotherapy treatment]. / Radiación ionizante recibida por pruebas de radiología intervencionista durante el tratamiento con quimioterapia intraarterial en pacientes afectos de osteosarcoma.

BACKGROUND: Osteosarcoma paediatric patients are usually treated with intra-arterial chemotherapy (QTia) which is admi-nistered directly to the tumour. This procedure exposes patients to ionizing radiation. Paediatric patients are especially sensitive to this exposure. METHODS: The total amount of ionizing radiation received from QTia administration was quantified in a group of 16 osteo-sarcoma paediatric patients from the Clínica Universidad de Navarra. RESULTS: The median of the total radiation received per patient was 33.4 Gy·cm2 (IQR: 43.33 Gy·cm2), and the median number of procedures performed per subject was 10 (IQR: 6.5). CONCLUSIONS: The study highlights the importance of quantifying the radiation received by a group of children and adoles-cents affected by osteosarcoma during treatment with QTia. Long-term side effects of this radiation should be considered in pae-diatric patients. Currently, there are no previous studies that provide data of the amount of ionizing radiation received through this procedure.

[The cytogenetic assay as a measure of genetic instability induced by genotoxic agents]. / El ensayo de micronúcleos como medida de inestabilidad genética inducida por agentes genotóxicos.

Human genetic integrity is compromised by the intense industrial activity, which emphasizes the importance to determine an "acceptable" genetic damage level and to carry out routine genotoxicity assays in the populations at risk. Micronuclei are cytoplasmatic bodies of nuclear origin which correspond to genetic material that is not correctly incorporated in the daughter cells in the cellular division; they reflect the existence of chromosomal aberrations and are originated by chromosomal breaks, replication errors followed by cellular division of the DNA and/or exposure to genotoxic agents. There are several factors able to modify the number of micronuclei present in a given cell, among them are age, gender, vitamins, medical treatments, daily exposure to genotoxic agents, etc. The cytogenetic assay for the detection of micronuclei (CBMN: cytokinesis-block micronucleus) is based on the use of a chemical agent, cytochalasin-B, which is able to block cytocinesis but allowing the nuclear division, therefore yielding binucleated and monodivided cells. The micronuclei scoring is performed on 1000 binucleated cells and the starting sample may vary, although most studies are performed on peripheral blood lymphocytes. The micronuclei assay is considered a practical, universally validated and technically feasible protocol which is useful to evaluate the genetic instability induced by genotoxic agents.

TNF-alpha promoter gene polymorphisms in Spanish children with persistent oligoarticular and systemic-onset juvenile idiopathic arthritis.

OBJECTIVE: To explore the possible association/s of the first reported tumour necrosis factor (TNF-alphaTNF-) alpha promoter gene polymorphisms -308, -238, -376 and -163 (G-->A) with systemic (SoJIA) and oligoarticular subtypes of juvenile idiopathic arthritis (JIA); and to test the association between these polymorphisms and the class I/class II HLA alleles in our population. METHODS: The patient group comprised 29 oligoarticular and 26 systemic Caucasian Spanish children with JIA; 68 healthy volunteers from the same ethnic group and geographical region served as controls. HLA alleles were determined using low-resolution polymerase chain reaction (PCR). TNF-alpha promoter gene polymorphisms were screened using PCR denaturing gradient gel electrophoresis (PCR-DGGE), followed, if positive, by restriction fragment length polymorphism (RFLP) analysis for identification. RESULTS: No statistical association was found between the four polymorphisms studied and JIA. However, the -308 G-->A polymorphism (TNF A2) tended to be more frequent in patients with SoJIA than in the oligoarticular group. TNF A2 was strongly associated with the extended haplotype A1B8DR3 (p = 0.003), and the tandem polymorphism -238/-376 in the presence of B18 and DR3. CONCLUSION: The TNF A2 allele was more frequent in SoJIA than in the oligoarticular group. TNF A2 can help to create a more inflammatory milieu in this JIA subtype, in combination with other polymorphisms involved in regulatory sequences of key molecules in the inflammatory response. The association of the -308 and -238/-376 polymorphisms with specific alleles of the HLA is reconfirmed.

[Vascular malformations as syndromic markers]. / Malformaciones vasculares como marcadores sindrómicos.

Vascular malformations are static lesions, generally present at the moment of birth, formed by displasic vessels that grow in proportion to the growth of the child. They show normal cell replacements that constitute genuine mistakes of morphogenesis. The absence of regression of these malformations implies that they remain throughout the lifetime. The terminology describing this type of lesions gave rise to confusion in the medical literature until the International Society for the Study of Vascular Anomalies adopted a classification based on the dominant vessel of the malformation in 1996. This classification distinguishes between simple and complex forms depending on whether they affect one or several types of vessel. Vascular malformations can show themselves as isolated lesions or can be associated with other lesions, constituting the guide sign or being the principal marker of some syndromic complexes. This paper describes the principal signs and symptoms of those syndromes in which a vascular malformation is the key that raises suspicion about the existence of other associated lesions.

Current role for resection of thoracic metastases in children and young adults--do we need different strategies for this population?

UNLABELLED: A retrospective review of surgical interventions for pulmonary metastases found 44 surgical metastasectomies in patients 20 years old or younger. OBJECTIVE: Indications for pulmonary metastasectomy are well established in adults, but are not so clear when we are dealing with a younger population. PATIENTS AND METHODS: A retrospective review of surgical interventions for pulmonary metastases (from December 1996 to October 2001) found 44 surgical metastasectomies in patients considered pediatric or young adults (20 years old or younger). Initial primary tumor, disease-free interval (DFI), previous thoracotomies, tumor histology, number of metastases, surgery performed, postoperative complications, other treatments received, and outcomes were recorded. RESULTS: Median age was 16.3 years (range 5 to 20 years) with 27 male and 17 female patients. Primary tumors were sarcoma (n = 31), Ewing's tumor (n = 8), Wilms' tumor (n = 3), and testicular carcinoma (n = 2). 27 patients had undergone previous resection of pulmonary metastases. Approaches were posterolateral thoracotomy (n = 18), clamshell incision (n = 8), VATS (n = 7), axillary thoracotomy (n = 9), and others (n = 2). Wedge resections were the procedure of choice (n = 35). In very select cases 1 pneumonectomy, 3 lobectomies, 2 chest wall resections, and 1 spinal surgery (vertebrectomy) were performed. Intra-operative radiotherapy (IORT) was employed in 2 patients. Cardiopulmonary bypass was necessary in 1 patient in order to resect an intra-atrial tumor thrombus. There was no operative mortality. Morbidity was related to prolonged air leaks (3 patients), hemothorax (2 patients), cerebrospinal fluid leak (1 patient), atelectasia (1 patient), peritoneal pain (1 patient), and postoperative fever syndrome (1 patient). Patterns of failure were thoracic (lung-pleura-chest wall) (n = 20), distant (n = 3) and thoracic + distant (n = 6). CONCLUSION: A close collaboration between oncologists, radiotherapists, and surgeons is mandatory in order to obtain good results. IORT is an interesting option. Better results are obtained if there is a long DFI and probably justifies a more aggressive approach in these specific cases.

Serotonergic polymorphisms and psychotic disorders in populations from North Spain.

There is strong biological evidence relating alterations in the serotonergic system with mental disorders. These alterations may be originated at the DNA level by sequence mutations that alter the functioning of serotonin receptors and transporter. To test this hypothesis we investigated three genetic variants of the 5-HT2A receptor (-1438G/A, 102T/C and His452Tyr) and two variants of the serotonin transporter (a VNTR in the second intron and a 44 bp insertion/delition in the promoter region of the gene) in a clinical sample recruited in a human isolate and in surrounding areas in Northern Spain (N = 257) and in ethnically matched controls (N = 334). No clear association was found between 5-HT2A variants and psychosis. However, marginal associations were observed between the 5-HTT LPR and VNTR variants and psychosis (P < or = 0.05) indicating a minor contribution to psychosis of genetic alterations in this gene.

Bone metastases from osteosarcoma.

Bony metastases in patients with osteosarcoma are unusual and normally appear late in the course of the disease. We report our experience with eight such patients, four with solitary and four with multiple metastases. Those with solitary metastases were treated as new tumours with neoadjuvant chemotherapy and surgery. Three remain alive with no evidence of disease at 5, 7 and 8 years follow-up respectively. Histology and response to neoadjuvant chemotherapy was similar in both the primary and metastatic lesions and is a predictive factor of outcome. Those with multiple metastases were treated by palliative measures, and none survived. We conclude that resection of solitary metastases from osteosarcoma after neoadjuvant chemotherapy can be curative.

Transient posterior encephalopathy induced by chemotherapy in children.

The cases of three children, 16, 12, and 12 years of age, who suffered sudden confusional state and cortical blindness lasting 12 to 30 minutes while under treatment with high-dose methotrexate, cyclophosphamide, and dactinomycin for a lower limb osteosarcoma are reported. Transient neuropsychologic deficits arose after the acute phase of treatment: left hemispatial neglect and constructive apraxia (Patient 1); constructive apraxia (Patient 2); and constructive apraxia and alexia without aphasia (Patient 3). The three patients recovered completely from all their deficits within the time frame of 3 hours to 2 weeks. Arterial hypertension and hypomagnesemia were found during the acute phase in all patients. In Patients 2 and 3, magnetic resonance imaging revealed increased parieto-occipital T(2) signal involving gray and white matter. In Patients 1 and 2, HmPAO-SPECT revealed parieto-occipital hypoperfusion that resolved a few days later. The alterations detected by neuroimaging were concurrent with the appearance and disappearance of the clinical symptoms. Such transient acute episodes have been named occipital-parietal encephalopathy. On the basis of our clinical, laboratory, and neuroimaging findings, an explanation for the origin of this syndrome, a migrainelike mechanism, triggered by chemotherapy-induced hypomagnesemia, is proposed.

[Characteristics and value of chromosome aberrations induced by antitumor treatments in pediatric patients with cancer]. / Características y valor de las aberraciones cromosómicas inducidas por los tratamientos antitumorales en pacientes pediátricos con cáncer.

Cytogenetic studies were performed on 80 pediatric cancer patients to test the chromosomal damage induced by the chemotherapy treatments. G-banded karyotypes were performed on peripheral blood lymphocytes (PBL) (n = 127) obtained at diagnosis, during treatment, at remission and at relapse. We detected a significant increase in the number of altered karyotypes in the samples during treatment, lowering to similar values to those at diagnosis at two-year remission. Most of the chromosomal aberrations (CA) detected during chemotherapy were unbalanced (75%) and affected most frequently chromosomes 1, 3, 5, 6, 11, 12, 16 and 17. There was also a marked increase of CA in samples at relapse, with similar features (type and distribution) to those detected during treatment. There was an outstanding correlation between the chromosomal breakpoints in our series and fragile sites (58%), oncogene (75%) and tumour suppressor gene (33%) loci described in the literature. The results obtained suggest that the cytostatic drugs induce a transient increase in chromosome fragility that focuses to several cancer-associated breakpoints.

Nonclonal chromosomal aberrations induced by anti-tumoral regimens in childhood cancer: relationship with cancer-related genes and fragile sites.

Cytogenetic studies were performed on 80 pediatric cancer patients to observe the chromosomal damage, both quantitative and qualitative, induced by chemotherapy. Peripheral blood lymphocytes (PBL) (n = 127) were obtained at diagnosis, during treatment, at remission, and at relapse, and chromosome analysis performed utilizing G-banding standard procedures. The results show a significant increase in the number of altered karyotypes (P = 0.03) in the samples during treatment, returning to values that were similar to those at diagnosis at 2-year remission. Most of the chromosomal aberrations (CA) detected during the chemotherapy regimens were nonclonal, unbalanced (75%), and involved chromosomes 1, 3, 5, 6, 11, 12, 16, and 17 most frequently. There was also a marked increase of CA in samples at relapse with very similar features (type and distribution) to those detected during treatment. There was a good correlation between the chromosomal breakpoints in our series and fragile sites (58%), oncogene (75%), and tumor suppressor gene (33%) loci described in the literature. The results obtained suggest that cytostatic drugs induce a transient increase in chromosome fragility occurring at several cancer-associated breakpoints.

[Analysis of the involvement of the tumour suppressor genes TP53, p16INK4, p21WAF1, RB1 and the drugs metabolizing enzymes in the development of bone tumours in children]. / Análisis de la implicación de los genes de supresión tumoral TP53, p16INK4, p21WAF1, RB1 y de las enzimas metabolizadoras de drogas en el desarrollo de tumores óseos en niños.

BACKGROUND: Several tumor suppressor genes such as p16INK4, TP53, RB1 y p21WAF1 are involved in cell cycle regulation in response to DNA damage and belong to the complex pathway that regulates cell proliferation and/or differentiation. We have investigated the presence of mutations in those genes and polymorphisms of Drug Metabolizing Enzymes that could be involved in the development of pediatric bone tumors or in their outcome. MATERIALS AND METHODS: By means of PCR-based techniques, we have analyzed the presence of variations in the coding sequence of p16INK4, TP53, RB1 y p21WAF1 and of the Drug Metabolizing Enzymes in a group of 82 osteosarcomas and 47 Ewing's sarcomas as well as in a control group of 115 healthy children. RESULTS: We detected mutations of the TP53 gene in about 25% of the samples analyzed, most frequently in association with tumors of poor prognosis or reduced survival. The p16INK4 gene was homozygously deleted in 18% of the osteosarcomas, also associated with poor prognosis and unfavourable histologic subtypes; RB1 was altered in 21% of the osteosarcomas. We did not detect relevant associations between polymorphisms of the Drug Metabolizing Enzymes or mutation of the p21WAF1 and development of pediatric bone tumors. CONCLUSIONS: Alteration of TP53, p16INK4 and p21WAF1 seems to be involved in the development of pediatric bone tumors and to be an unfavourable prognostic factor in this type of tumors.

Clinical and molecular features of Ewing sarcoma in a patient with triple-X syndrome.

A case of Ewing sarcoma in a 16-year-old girl with 47 XXXc karyotype is reported.

Screening of the human tumor necrosis factor-alpha (TNF-alpha) gene promoter polymorphisms by PCR-DGGE analysis.

We have designed a new PCR-DGGE technique that enables detection of base changes in the TNF-alpha gene promoter. Screening of 130 samples from Spanish children has shown that this technique accurately detects the altered band patterns induced by the presence of the polymorphisms at positions -376, -308, -238 and -163 of the promoter sequence. Although further analysis are needed to fully characterise the alterations detected, we believe that this PCR-DGGE technique is a rapid and sensitive first approach to the genetic characterisation of the TNF-alpha promoter.

Cost-effectiveness analysis of tropisetron vs. chlorpromazine-dexamethasone in the control of acute emesis induced by highly emetogenic chemotherapy in children.

OBJECTIVE: To perform a cost-effectiveness analysis (CEA) between a standard antiemetic regimen-chlorpromazine + dexamethasone (CPM-DEX)- and a 5-HT3 receptor antagonist-tropisetron (TROP)--in the control of acute emesis induced by highly emetogenic chemotherapy in children, considering two analytic perspectives: hospital and patients. METHODS: The CEA was performed by constructing a decision tree, for both analytic perspectives, of the possible outcomes of treatment with TROP (single 0.2 mg/kg i.v.) or CPM (5-15 mg i.v. infusion for 3 doses) plus DEX (2 mg/m2 i.v. bolus i.v. x2). The patients were stratified by age in two groups (2-12 and 13-17). To estimate the probability of each endpoint at the decision tree we have taken as a base a trial developed in the Department of Pediatrics. Direct medical cost of primary therapy, failure, complications and side effects were included in the cost calculations. RESULTS: From patients' analytic perspective, TROP was more cost-effective than CPM-DEX for both groups of patients. Discrepancy between both analytic perspectives in 13-17 year-old patient's group was resolved in favour of the option chosen from the patients' analytic perspective (TROP). Sensitivity analysis showed the reliability of the results. CONCLUSIONS: 1. TROP was more cost-effective than CPM-DEX. 2. Taking into account the patients' analytic perspective is essential when we compare antiemetics pharmacoeconomically. 3. It seems necessary to increase the effectiveness of TROP in pediatric patients receiving highly emetogenic chemotherapy with strategies such as the addition of a steroid.

Combined surgical approach for sarcoma lung metastasis with atrial involvement.

A 20-year-old patient, who had been treated for a femur sarcoma with pulmonary metastases 8 years before, arrived at our institution with a new metastatic hilar lung nodule. During the standard lobectomy procedure an unexpected atrial invasion by the tumor was discovered. Intraoperative transesophageal echocardiography (TEE) showed a big pediculated tumor in the atrium. Cardiopulmonary bypass (CPB) was required in order to safely resect the atrial wall with the tumor. The atrial defect was repaired with a pericardial patch. Postoperative course was uneventful. After 14 months, the patient is asymptomatic and free of disease.

Lack of gene amplification as a mechanism of CDK4 activation in human neuroblastoma.

Neuroblastoma is the most frequent solid tumor in childhood. We have analysed 48 neuroblastomas of different stages and degrees of cellular differentiation for CDK4 amplification by a fluorescent differential PCR assay. We explored the relative densitometric measure of a 119 bp fragment of the CDK4 gene versus an 82 bp fragment of the IFNG gene. We were not able to detect any case of CDK4 gene amplification in the neuroblastomas. In conclusion, CDK4 activation does not seem to be relevant to the development of neuroblastomas, at least through gene amplification.

Ewing family tumors: potential prognostic value of reverse-transcriptase polymerase chain reaction detection of minimal residual disease in peripheral blood samples.

In more than 95% of patients, the Ewing family of tumors (ET) has chimeric transcripts caused by fusion of the EWS gene to either FLI1 or ERG. The presence of specific EWS-FLI1 or EWS-ERG transcripts in peripheral blood (PB) samples of patients being treated for ET was prospectively evaluated, and these data were correlated to their clinical status. The authors studied 113 PB samples from 28 patients with ET. Treatment included chemotherapy, radiotherapy, and surgical excision of tumor after induction therapy. PB samples were taken prospectively at least 2 weeks after resection of tumor. Nested reverse-transcriptase polymerase chain reaction (RT-PCR) followed by Southern blot was performed in all samples. Resected tumors were reviewed for the degree of response to chemotherapy and volume. Seventy-seven PB samples from 28 patients had EWS-FLI1/ERG transcripts. In 11 patients, PB samples became negative with treatment, and, in 5 of them, the samples remained negative throughout the study. Samples taken during progression were always positive and, in 4 patients, became positive before progression was clinically evident. All patients with transcripts other than EWS-FLI1 type 1 (n = 3) died from tumor progression. This is a sensitive assay to monitor circulating tumor cells in Ewing tumors. The preliminary data suggest that progression is preceded by positive samples and may be related to specific transcript types.

Differential polymerase chain reaction: a technical comparison of three methods for the detection of CDK4 gene amplification in glioblastomas.

Among the different techniques used to detect oncogene amplification in tumor DNA, Southern blot and differential PCR have been the most frequently used. We report on a technical comparison of three different methods to detect gene amplification by differential PCR: ethidium bromide staining, silver staining (both after standard differential PCR), and fluorescent differential PCR. We explored the relative densitometric measure of a 119 bp fragment of the CDK4 gene versus an 82 bp fragment of the IFNG gene. In total agreement with previous studies carried out by Southern blot and differential PCR by other authors, we were able to detect CDK4 amplification in 3 of the 21 glioblastomas (14%), but only by the fluorescent differential PCR method. In conclusion, fluorescent differential PCR is more sensitive than standard differential PCR for detection oncogene amplification in tumor DNAs.