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Biomedical subjects

E Quintana

Publications and source records attributed to E Quintana.

At least 37 records · Page 2Linked to original sources
PubMed1998

Cytogenetic analysis of South Asian berry pickers in British Columbia using the micronucleus assay in peripheral lymphocytes.

Micronuclei in peripheral blood lymphocytes from British Columbia seasonal farmworkers and controls were evaluated using the cytokinesis-block technique. The farmworkers harvested berry crops and were likely occupationally exposed to pesticides. Subjects were 39 female subjects of South Asian descent; 18 farmworkers employed during 1993 and 21 age-matched controls. The mean age was 55.9 years. Micronuceli were also scored for the presence of kinetochores. No significant difference was found between the frequency of micronucleated binucleates in the farmworkers group (19.20/1000 binucleates), and the control group (21.76/1000 binucleates). However, among the farmworkers employed in 1993, there was a positive, but not statistically significant, association between micronucleated cell frequency and weeks worked: 16.44/1000 binucleates in those working less than 20 weeks; 23.78/1000 binucleates in those working 20 to 23 weeks; and 25.43/1000 binucleates in those working more than 23 weeks. In those who had ever been employed as farmworkers, there was an elevated frequency of micronucleated cells in the group with the longest history of employment as a farmworker (25.28/1000 binucleates) compared to those with the shortest employment history (16.48/1000 binucleates). This trend remained evident after adjusting for age, red blood cell folate, meat consumption, coffee consumption and recent vaccination. A positive association between the consumption of meat and micronucleus frequency was also observed. Non-meat eaters were likely life-long vegetarians. Micronuclei in farmworkers had a lower frequency of kinetochore positive micronuclei than controls. This study indicates that South Asian berry pickers in British Columbia may be at risk for genetic damage. More studies in other ethnic groups and in males are needed to generalize the findings of this study. More direct measures of exposure are needed to elucidate the sources of genotoxicity.

Adult↗
PubMed1998

Treatment of non-metastatic rhabdomyosarcomas in childhood and adolescence. Results of the second study of the International Society of Paediatric Oncology: MMT84.

The second International Society of Paediatric Oncology (SIOP) study for rhabdomyosarcoma (MMT84) had several goals. The two principal aims were: (1) to improve the survival of children with rhabdomyosarcoma; and (2) to reduce the late effects from therapy by restricting the indications for surgery and/or radiotherapy after good response to initial chemotherapy. A further aim was to investigate the role of high-dose chemotherapy in young patients with parameningeal primary tumours. 186 previously untreated eligible patients entered the study. Patients with completely resected primary tumour received three courses of IVA (ifosfamide, vincristine and actinomycin D). Patients with incompletely resected tumour received six to 10 courses of IVA according to stage. Patients achieving complete remission with chemotherapy alone did not usually receive radiotherapy or undergo extensive surgery, but patients remaining in partial remission received local therapy with surgery and/or radiotherapy. Only patients over 5 years of age with parameningeal disease and patients over 12 years with tumours at any site were given systematic irradiation. Complete remission was achieved in 91% (170/186) of all patients. With a median follow-up of 8 years, the 5-year overall survival was 68% (+/- 3% standard error of the mean (SEM) and the 5-year event-free survival 53% (+/- 4% SEM). These results show an improvement over previous SIOP study (RMS75) in which survival was 52% and event-free survival was 47%. Among the 54 patients who exhibited isolated local relapse, 35% (19/54) survived in further remission longer than 2 years after retreatment, including local therapy (surgery +/- radiotherapy). Analysis of the overall burden of therapy received by all surviving children (including primary treatment and treatment for relapse if required) showed that 24% (28/116) were treated by limited surgery followed by three courses of IVA, 29% (34/116) were treated by chemotherapy alone (after initial biopsy) and 13% (15/116) received chemotherapy plus conservative local treatment (limited surgery or radiotherapy for residual disease). Only 34% (39/116) received intensive local therapy defined as radical wide field radiotherapy or radical surgery or both. Compared with the results obtained in the previous SIOP study, treatment in MMT84 was based on response to initial chemotherapy and, despite an overall reduction of the use of local therapy, significantly improved survival for patients with non-metastatic disease. This trial, also for the first time, provides evidence that retreatment after local relapse can achieve long-term second remissions.

Adolescent↗
PubMed1998

Role of chemotherapy alone or in combination with hyperthermia in the primary treatment of intraocular retinoblastoma: preliminary results.

BACKGROUND: The efficacy of the etoposide-carboplatin combination in extraocular retinoblastoma is well known. This drug combination is therefore used in intraocular retinoblastoma, as primary reduction chemotherapy, before local treatment. The use of carboplatin in combination with diode laser hyperthermia as local treatment (thermochemotherapy) has been recently described as a conservative approach avoiding external beam radiotherapy in posterior pole tumours. METHODS: All patients were reviewed, who were treated for retinoblastoma at the Institut Curie between June 1994 and October 1995, in whom treatment included either reduction chemotherapy or thermochemotherapy or both modalities successively. 23 patients presenting with unilateral (three) or bilateral (20) intraocular retinoblastoma received neoadjuvant chemotherapy consisting of two courses of etoposide 150 mg/m2/day and carboplatin 200 mg/m2/day for 3 days. 15 patients (17 eyes), eight of whom had already received neoadjuvant chemotherapy, were treated by thermochemotherapy. RESULTS: Neoadjuvant chemotherapy: overall, seven eyes in seven patients could be treated conservatively, avoiding external beam irradiation, with a median follow up of 14 months. Thermochemotherapy: external beam irradiation was avoided for 14 of the 17 eyes treated. CONCLUSION: Integration of neoadjuvant chemotherapy and combined treatment with carboplatin and diode laser, into the therapeutic armamentarium for retinoblastoma allows use of more aggressive treatments such as enucleation and external beam radiation.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1998

High-dose melphalan, etoposide, and carboplatin followed by autologous stem-cell rescue in pediatric high-risk recurrent Wilms' tumor: a French Society of Pediatric Oncology study.

PURPOSE: The three-drug combination of melphalan (M), etoposide (E), and carboplatin (C) followed by autologous stem-cell (ASC) rescue has been evaluated prospectively by the French Society of Pediatric Oncology (SFOP) in pediatric high-risk recurrent (HRR) Wilms' tumor (WT) patients with chemotherapy-responsive disease. PATIENTS AND METHODS: From October 1988 to October 1994, 29 patients with HRR WT were treated in nine SFOP centers. Two additional patients with stage IV anaplastic WT were consolidated in first complete response (CR) with the same regimen and have been studied separately. The regimen consisted of M 180 mg/m2 for 1 day, E 200 mg/m2/d for 5 days, and C at a daily targeted area under the concentration-time curve (AUC) of 4 mg x min/mL for 5 days. ASCs were reinfused 48 hours after M. RESULTS: Twelve of 28 assessable patients with HRR WT are still in continuous CR at a median of 48.5 months (range, 36 to 96) after consolidation. Disease-free survival (DFS) and overall survival (OS) estimated by the Kaplan-Meier method at 3 years were 50%+/-17% and 60%+/-18%, respectively. Sixteen patients relapsed at a median of 8.5 months (range, 3 to 53) after consolidation. Toxicity data are available in 31 grafted patients. Grade III and IV toxicities included hematologic side effects (n=31), hemorrhage (n=8), mucositis (n=24), diarrhea (n=12), renal disorders (n=8), and pneumonitis (n=3). CONCLUSION: The adverse prognostic factors (APF) used to select patients for this dose-intensive chemotherapy define children with very-poor-risk recurrent WT. Despite high treatment-related toxicity, about half of these patients remain disease-free at 3 years. Patient outcome is statistically better when high-dose chemotherapy (HDCT) is performed as early as the second CR or partial response (PR). Novel therapeutic approaches with innovative preparative regimens are warranted for the remaining high-risk patients.

Adolescent↗
PubMed1998

[Unilateral retinoblastomas with late bilateralization. Three case reports].

Three cases of unilateral retinoblastoma with late bilateralization are presented in this study. The rare occurrence of this event underlines the need for prolonged follow-up in the fellow-eye, even in the absence of familial retinoblastoma. In these three cases, the first affected eye was enucleated after a diagnosis made at three months, sixteen months and three years of age. New tumors appeared in the second eye when the children were sixteen years old in one case and five years old in two cases.

Adolescent↗
PubMed1997

High-dose chemotherapy with carboplatin, etoposide and cyclophosphamide followed by a haematopoietic stem cell rescue in patients with high-risk retinoblastoma: a SFOP and SFGM study.

This study investigates the role of high-dose chemotherapy with haematopoietic stem cell rescue as consolidation treatment in high-risk retinoblastoma (extraocular disease at diagnosis or relapse or invasion of cut end of optic nerve). 25 patients received high-dose chemotherapy including carboplatin (250 mg/m2/day from day 1 to day 5 for the 6 first patients and 350 mg/m2/day from day 1 to day 5 for the other patients), etoposide (350 mg/m2/day from day 1 to day 5) and cyclophosphamide (1.6 g/m2/day from day 2 to day 5) (CARBOPEC) followed by autologous haematopoietic stem cell rescue. 19 patients received this drug combination for chemosensitive extraocular relapse. The other 6 patients with histological high-risk factors were given this treatment as consolidation after enucleation and conventional chemotherapy. The three year disease-free survival was 67.1%. In 7 of the 9 relapsing patients, the first site of relapse was the central nervous system. All patients with central nervous system disease died except one. The main toxicity was haematological and digestive (mucositis and diarrhoea). 2 of the 13 evaluable patients had grade III and IV ototoxicity. One patient experienced an acute grade I reversible cardiotoxicity. The CARBOPEC regimen seems to be a promising therapeutic strategy in patients with high-risk retinoblastoma, especially those with bone and/or bone marrow involvement. This treatment did not improve the outcome of patients with central nervous system disease.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1997

Serial surveillance cultures of skin and catheter hub specimens from critically ill patients with central venous catheters: molecular epidemiology of infection and implications for clinical management and research.

A prospective study of 45 central venous catheters was conducted to assess, by strain delineation, the turnover of skin and catheter hub (superficial) colonization and the relative contributions of catheter hub and skin colonization to catheter tip colonization. Serial quantitative cultures of skin and catheter hub were performed. Catheter tip, blood, and specimens for culture from targeted superficial sites (TSSs) were also collected at the time of catheter removal. Strains from 17 tip-positive catheters were delineated by pulsed-field gel electrophoresis. Only 12 (28.6%) of 42 skin strains and 14 (31.1%) of 45 catheter hub strains were found to be present at the time of catheter removal. In addition, only 9 (29.0%) of the 31 tip-colonizing strains were present on TSSs. Moreover, 15 (48.4%) of the 31 tip-colonizing strains had a superficial origin, and the other 16 (51.6%) were of unknown origin. In catheters suspected of infection, cultures of TSSs had a negative predictive value for catheter-related bacteremia of 94.4% but a positive predictive value of 44.4%. When the causative agent was identified (to the strain level) these values dropped to 80.9 and 18.7%, respectively. The study shows that skin and catheter hub colonization is a common, dynamic phenomenon. Strains recovered from TSSs showed a low level of correlation with strains from previous cultures of specimens from superficial sites and catheter tip isolates. Consequently, TSSs cannot be recommended for use in determining the therapy. However, catheter-related bacteremia is uncommon when cultures of TSSs are negative.

Bacteria↗
PubMed1996

Histopathologic risk factors in retinoblastoma: a retrospective study of 172 patients treated in a single institution.

BACKGROUND: Microscopic extrascleral involvement and involvement of optic nerve resection line are accepted risk factors for orbital and/or metastatic disease from retinoblastoma. Conversely, choroidal and retrolaminar optic nerve involvement are questionable risk factors. The aim of this retrospective study was to define the histopathologic risk factors for orbital and/or metastatic disease in patients treated by first-line enucleation. METHODS: Histopathologic review of 172 evaluable patients treated at Institut Curie between 1977 and 1990 determined the degree of choroidal (minimal or massive), scleral (intra- or extrascleral), optic nerve (prelaminar, retrolaminar with or without resection line involvement), and anterior chamber invasion. The degree of differentiation was also analyzed. The log rank test was used for univariate analysis and the Cox regression model was used for multivariate analysis. RESULTS. Eighty-seven percent of the 172 patients were disease free at 3 years. Twenty-three patients developed retinoblastoma recurrence. The disease-free survival was significantly different among the five subgroups of choroidal or scleral invasion (P = 3 x 10(-3). The differences among the four subgroups of optic nerve invasion were also significant (P = 10(-4)). Classical factors were confirmed in our series (extrascleral involvement and involvement of optic nerve resection line). Multivariate analysis of the 149 patients without these classical risk factors revealed two factors that increase the risk of orbital and/or metastatic disease: massive choroidal invasion and postlaminar optic nerve involvement. CONCLUSIONS: In our experience, retrolaminar optic nerve involvement, with free resection line, and massive choroidal invasion significantly increase the risk for orbital and/or metastatic disease.

Adolescent↗
PubMed1996

Cerebrospinal fluid examination in a case of childhood orbital granulocytic sarcoma.

The diagnosis of a case of childhood orbital granulocytic sarcoma, initially classified as a poorly-differentiated malignant tumor, was finally considered at the time of relapse following primary treatment with chemotherapy and local irradiation. At this time, systematic cerebrospinal fluid examination showed numerous blast cells with Auer rods, consistent with the diagnosis of meningeal acute myeloid leukemia of M2 type, and concomitant biopsy of the tumor indicated the diagnosis of chloroma. Reevaluation of the primary biopsy confirmed this diagnosis.

Biopsy↗
PubMed1995

A randomized comparison of intravenously administered granisetron versus chlorpromazine plus dexamethasone in the prevention of ifosfamide-induced emesis in children.

PURPOSE: To compare the efficacy and safety of intravenously administered granisetron with those of chlorpromazine plus dexamethosone in the prevention of ifosmamide-induced emesis in children with malignant disease. PATIENTS AND METHODS: Eighty-eight children, aged 2 to 17 years, were scheduled for ifosfamide therapy (> or = 3 gm/m2) for 2 or 3 consecutive days. On each day, children received granisetron, 20 microgram/kg intravenously, before ifosfamide therapy, plus up to two more doses within 24 hours if required, or chlorpromazine, 0.3 to 0.5 mg/kg intravenously, every 4 to 6 hours, plus dexamethasone, 2 mg/m2 intravenously every 8 hours. RESULTS: During the initial 24 hours, significantly fewer episodes of vomiting were recorded after granisetron administration (median number, 1.5 vs 7.0; p = 0.001), and the percentages of children having no more than one vomiting episode (51% granisetron vs 21% chlorpromazine-dexamethasone) and no worse than mild nausea (67% granisetron vs 38% chlorpromazine-dexamethasone) were lower after granisetron therapy (p < 0.01). Fewer children had sedation with granisetron (2 vs 19; p < 0.001); there were no extrapyramidal reactions during granisetron therapy compared with two during control therapy. CONCLUSION: Granisetron was superior to chlorpromazine-dexamethasone antiemetic therapy for children receiving ifosfamide therapy and deserves further study during other chemotherapy regimens.

Adolescent↗
PubMed1994

The role of chemotherapy in orbital involvement of retinoblastoma. The experience of a single institution with 33 patients.

BACKGROUND: Orbital involvement is a rare occurrence in retinoblastoma but still carries a bad prognosis. The aim of this study was to define more clearly the role of chemotherapy in this advanced disease. METHODS: Between 1977 and 1991, 33 patients were treated at the Services de Pédiatrie at Institut Curie (Paris, France) for orbital involvement of retinoblastoma, which was isolated in 20 patients and associated with metastases in 13 patients (outside the central nervous system [CNS], 6; within the CNS, 7). Treatment included chemotherapy for 33 patients, irradiation of the orbit for 23 patients, and intrathecal chemotherapy and/or CNS irradiation in selected patients. RESULTS: The plateau phase of the survival curve was reached at 15 months, with a survival of 34% plus or minus 8%. The disease free interval was longer when patients had no CNS disease (P < 0.05). Twenty of the 21 recurrences (95%) occurred within 1 year after diagnosis of orbital involvement. CONCLUSIONS: Intensive chemotherapy using cyclophosphamide, platinum compounds, epipodophyllotoxins, doxorubicin, and vincristine was effective in orbital involvement of retinoblastoma even with associated extra-CNS metastases. However, associated CNS disease still carries a bad prognosis, and long term follow-up is necessary to evaluate the risk of a second tumor.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

Risk factors for infection by Pseudomonas aeruginosa in patients with ventilator-associated pneumonia.

OBJECTIVE: to investigate the epidemiology of infection by Pseudomonas aeruginosa in patients with ventilator-associated pneumonia (VAP). DESIGN: prospective clinical study. SETTING: a medical-surgical ICU in a university hospital. PATIENTS: we followed-up 568 mechanically ventilated patients and 83 episodes of VAP with etiologic diagnosis in 72 patients were retained for analysis. RESULTS: Ps. aeruginosa was isolated in 22 (26.5%) episodes in 18 patients. Of these episodes 7 were directly responsible for death. Using logistic regression analysis, the risk of VAP due to Ps. aeruginosa was increased in patients with chronic obstructive pulmonary disease (relative risk (RR) = 29.9, 95% confidence interval (CI) = 4.86-184.53), a mechanical ventilation period longer than 8 days (RR = 8.1, 95% CI = 1.01-65.40) and prior use of antibiotics (RR = 5.5, 95% CI = 0.88-35.01). CONCLUSIONS: patients with VAP and these factors have a greater risk of infection by Ps. aeruginosa and empirical therapy for these episodes should include anti-pseudomonal activity until etiologic diagnosis is established.

Adult↗
PubMed1994

Nosocomial bacteremia in a medical-surgical intensive care unit: epidemiologic characteristics and factors influencing mortality in 111 episodes.

OBJECTIVE: To analyze the epidemiology and factors influencing mortality of ICU-acquired bacteremia. DESIGN: Prospective clinical study. SETTING: A medical-surgical ICU in an university hospital. PATIENTS: We recorded variables from 111 consecutive ICU-acquired episodes for a 3-year period. RESULTS: The attack rate was 1.9 episodes per 100 patient-days. The commonest isolates were coagulase-negative staphylococci, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. Intravascular catheters were the most frequent source of infection. Overall mortality was 31.5%, and 65.7% of all deaths were directly attributable to infection. Bacteremia from intra-abdominal, lower respiratory tract or unknown origin were associated with a poor prognosis. A logistic regression analysis defined intraabdominal origin (p = 0.01, OR = 15.7) and presence of shock (p = 0.04, OR = 3.3) as independently influencing the risk of death. No significant differences were found for the remaining variables studied. CONCLUSIONS: Epidemiology and etiology of ICU-acquired bacteremia does not differ seriously in respect to nosocomial bacteremia among unselected populations, although it is associated with a greater incidence and overall mortality. Presence of shock is the most important modificable variable affecting the outcome.

Bacteremia↗
PubMed1994

Carboplatin treatment induces dose-dependent increases in the frequency of micronuclei in Ehrlich ascites tumor cells.

The effect of various doses (75-300 mg/kg b.w.) of carboplatin on the induction of micronuclei in Ehrlich ascites tumor (EAT) cells was studied. Carboplatin treatment resulted in a dose-dependent increase in the frequency of micronucleated EAT cells. Carboplatin treatment also decreased the mitotic index. The dose-effect curves were linear-quadratic for all the parameters studied. The maximal effect of the drug was obtained in all the treatments after 48 h.

Animals↗
PubMed1994

Primary chemotherapy in rhabdomyosarcomas and other malignant mesenchymal tumors of the orbit: results of the International Society of Pediatric Oncology MMT 84 Study.

PURPOSE: The MMT 84 multicentric prospective trial of the International Society of Pediatric Oncology (SIOP) was designed to (1) test the effectiveness of ifosfamide 3 g/m2 on days 1 and 2, vincristine 1.5 mg/m2 on days 1 and 14, and dactinomycin 0.9 mg/m2 on days 1 and 2 (IVA) repeated every 21 days; and (2) reduce late effects of treatment by reserving radiation therapy to the primary site for patients not achieving a complete response (CR) to primary chemotherapy. MATERIALS AND METHODS: Between 1984 and 1989, the MMT 84 study registered 34 children with nonmetastatic rhabdomyosarcomas (RMSs) and other malignant mesenchymal tumors (MMTs) of the orbit in this trial. RESULTS: The 4-year event-free survival rate is 62% +/- 9% (SD) and the 4-year survival rate 86% +/- 7% (SD). A total of 11 local recurrences occurred, 10 among 22 patients treated without initial radiation. Salvage of local failure was achieved in nine of 11 patients with the use of radiation and additional chemotherapy, but three later developed distant metastases and two have died. One isolated regional lymph node failure has occurred, while no patient relapsed with isolated distant metastases. Six of 12 patients who failed are alive with no evidence of disease from 16 to 50 months after relapse. The treatment was well tolerated in all patients, except for one with renal tubular acidosis and one who died of cardiotoxicity. Twelve patients remain in first remission without the use of radiation to the primary tumor from 27 to 84 months. CONCLUSION: Despite a higher incidence of local recurrence when treated by primary chemotherapy, early survival rates were not compromised and a significant number of patients avoided the late effects of radiation. However, longer follow-up is required to assess the ultimate outcome of patients treated in this manner.

Adolescent↗