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B de Camargo

Publications and source records attributed to B de Camargo.

At least 19 recordsLinked to original sources
PubMed2001

Immunohistochemical detection of p53 protein expression as a prognostic indicator in Wilms tumor.

BACKGROUND: Mutations of the tumor suppressor gene p53 are commonly found in several kinds of human cancer. In some types of neoplasms, accumulation of p53 protein has been reported to correlate with more aggressive clinical behavior. The role of p53 expression in Wilms tumors (WT) is not clear yet, but most studies have confirmed its correlation with anaplasia and advanced stage disease. PROCEDURE: Ninety-seven WT were evaluated for p53 expression by immunohistochemistry in formalin-fixed paraffin-embedded tissue and correlated with outcome. Tumors were classified as p53-Negative (p53-N) when no positivity was observed or only few cells showed weak positivity (0/1+) and p53-Positive (p53-P) when there was a diffuse and strong nuclear positivity (2+/3+). RESULTS: p53-P was detected in 13 out of 97 tumors and was associated with disease relapse (39 vs.17%; P = 0.06) but not with anaplasia. Among p53-N patients only 5% had metastatic disease compared with 31% of the p53-P sample. (P = 0.038). Overall survival was 94% for patients with p53-N vs. 85% for patients with p53-P at 1 year (P = 0.34). CONCLUSIONS: p53 expression in Wilms tumor detected by immunohistochemistry seems to be associated with advanced disease and relapse.

Biomarkers, Tumor↗
PubMed1999

The influence of parental age on the risk of Wilms' tumour.

The Brazilian Wilms' Tumour Study Group carried out a hospital-based multicentre case-control study of potential risk factors for the disease between April 1987 and January 1989. The parents of 109 cases of Wilms' tumour (WT) were interviewed when they were admitted to hospital for diagnosis and treatment. Also interviewed were the parents of two controls per case, matched for age, sex and interviewer, who were admitted to the same or nearby hospitals for treatment of non-neoplastic conditions. Odds ratios adjusted for family income and parental education were calculated by conditional logistic regression. Among cases diagnosed before 25 months of age there was a marked gradient of increasing risk of WT with increasing maternal age at the time of the child's birth. There was no increased risk for cases diagnosed after 25 months of age. The effects of paternal age were less marked. Possible explanations for these results are discussed.

Adult↗
PubMed1998

Experience with six children with fetal rhabdomyomatous nephroblastoma: review of the clinical, biologic, and pathologic features.

BACKGROUND: Fetal rhabdomyomatous nephroblastoma (FRN) is a rare variant of Wilms tumor. MATERIALS AND RESULTS: One hundred and thirty two children with kidney tumors were seen at our hospital from 1985 to 1993. Among them were 6 (4.5%) who had FRNs. Five were boys aged 8 months to 3 years; the girl was 17 months old. Three of the four with unilateral disease had tumors so large that they were considered unresectable at diagnosis. Five received pre-operative chemotherapy and three also received pre-operative radiation therapy. None of the tumors responded. Both patients with bilateral tumors died of progressive disease. Three of the four patients with unilateral disease followed for at least one year are alive for 1 to 10 years after diagnosis. CONCLUSIONS: FRN should be in the differential diagnosis of huge kidney tumors in children, and preoperative therapies escalated with caution since FRN is not responsive to treatment used for classic Wilms tumor.

Child, Preschool↗
PubMed1995

Parental exposures to pesticides and risk of Wilms' tumor in Brazil.

Wilms' tumor is one of the most common abdominal childhood malignancies. Wilms' tumor rates in Brazil are among the highest in the world. This prompted the Brazilian Wilms' Tumor Study Group to conduct a hospital-based, multicenter, case-control investigation of environmental risk factors for the disease. Between April 1987 and January 1989, the authors collected information on relevant occupational exposures by interviewing the parents of 109 Wilms' tumor cases admitted to hospitals in Sao Paulo, Salvador, Belo Horizonte, and Jau. Also interviewed were the parents of 218 age- and sex-matched control children who had been admitted for treatment of nonneoplastic diseases to the same or nearby hospitals. Odds ratios (ORs) adjusted for income and education were calculated by conditional logistic regression. Consistently elevated risks were seen for farm work involving frequent use of pesticides by both the father (OR = 3.24, 95% confidence interval (CI) 1.2-9.0) and the mother (OR = 128.6, 95% CI 6.4-2,569). These risk elevations were restricted to cases diagnosed after 2 years of age (ORs > 4), for paternal exposure, and after 4 years of age (OR = 14.8, 95% CI 2.2-98.8), for maternal exposure. Risk elevations were also more pronounced among boys (paternal exposure OR = 8.56, 95% CI 2.1-35.1; maternal exposure OR = 4.60, 95% CI 0.8-26.4) than among girls (paternal exposure OR = 1.31, 95% CI 0.4-4.1; maternal exposure OR = 2.03, 95% CI 0.5-8.9).

Age Factors↗
PubMed1995

Response to high-dose cisplatin and etoposide in advanced germ cell tumors in children: results of the Brazilian Germ Cell Tumor Study.

A trial was undertaken to assess the efficacy and toxicity of high-dose cisplatin and etoposide in children with newly diagnosed advanced malignant germ cell tumors. A total of eleven children and adolescents were treated with courses of high dose cisplatin 30 mg/m2/day and etoposide 120 mg/m2/day in five day cycles at 21 day intervals. There were eight girls and three boys, aged between 1 and 16 years (median: 120 months). Of nine unresectable tumors, six were in complete remission after three cycles and were completely resected. All patients are alive (median follow-up 17 months). Preliminary results shows that high dose cisplatin and etoposide is effective in controlling advanced malignant germ cell tumor.

Adolescent↗
PubMed1994

A randomized clinical trial of single-dose versus fractionated-dose dactinomycin in the treatment of Wilms' tumor. Results after extended follow-up. Brazilian Wilms' Tumor Study Group.

BACKGROUND: To verify the adequacy of a simplified chemotherapeutic regimen for the treatment of Wilms' tumor (WT), the authors conducted a clinical trial to compare the standard fractionated dose (15 mcg/kg x 5 days) of dactinomycin (AMD) with a single dose (60 mcg/kg x 1 day) administration of the drug. METHODS: From October 1986 to December 1988, 176 WT patients were enrolled in a randomized, multicentric clinical trial conducted by the Brazilian WT Study Group in 38 institutions from 8 states. Patients were randomly assigned to treatment arm A (standard 5-day fractionated AMD administration) or arm B (single high dose AMD administration) in the schedules most appropriate for their stage and histology. Except for the differences in AMD administration, patients were managed by the Third U.S. National WT Study protocol. The endpoints of interest were relapse free and overall survival. Complete follow-up information was obtained until December 1992. RESULTS: After a median follow-up of 47 months, there were no significant differences in survival distributions between treatment arms, using data for all patients or data stratified by disease stage. Relapse free and overall 4-year rates were similar in both groups: 67% and 72%, respectively, in arm A, and 67% and 75%, respectively, in arm B (P = 0.839 and 0.710, respectively). Patients assigned to the simplified arm had cumulatively 1921 fewer hospital days as compared with those receiving the fractionated dose. Hepatic toxicity was observed in only one patient assigned to the divided dose regimen and in none of the single dose group. CONCLUSIONS: WT can be treated using a single dose regimen for AMD administration, thus minimizing the inconvenience for the children and their parents and reducing considerably health care delivery costs.

Child, Preschool↗