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Biomedical subjects

A Rey

Publications and source records attributed to A Rey.

At least 91 records · Page 5Linked to original sources
PubMed1998

Lymphatic spread in stage Ib and II cervical carcinoma: anatomy and surgical implications.

OBJECTIVE: To determine the frequency and topography of pelvic and para-aortic node involvement in cervical carcinoma and to identify the appropriate level for resection of the lymphatic chains. METHODS: Between 1985 and 1994, 421 women with stage Ib or II cervical carcinoma were treated by surgery in combination with irradiation. Each underwent a radical hysterectomy with systematic pelvic and para-aortic lymphadenectomy. RESULTS: A median of 34 lymph nodes were removed per patient. The overall frequency of lymph node involvement was 26%, and the frequency of para-aortic metastases was 8%. The frequency of lymph node metastasis was associated significantly with stage (chi(2) = 7.8; P < .02), tumor size (chi(2) = 14.8; P < .001), and patient age (chi(2) = 5.9; P < .05). The frequency of para-aortic involvement was below 3% in patients with small tumors (under 2 cm). When pelvic nodes were involved, the obturator group was concerned in 76 cases (18%) and the external iliac group in 48 patients (11%). When para-aortic nodes were involved, the left para-aortic chain was the most frequently concerned (23 patients [5%]). In eight of these patients, nodal involvement was found only above the level of the inferior mesenteric artery. Among 106 patients with pelvic positive nodes, 28 (26%) also had para-aortic metastatic nodes. CONCLUSION: Para-aortic lymphadenectomy should remove all of the left para-aortic chain (inframesenteric and supramesenteric) and so should be performed up to the level of the left renal vein. According to the low frequency of para-aortic involvement when tumor size is below 2 cm, such a procedure could be avoided in patients with small tumors.

Adult↗
PubMed1998

Opiate agonist-induced changes in behavioral sensitivity to clonidine are observed in perinatally malnourished rats exposed to chronic stress.

Sensitivity of alpha2-adrenoceptors following repeated immobilization sessions plus morphine (MOR) or beta-endorphin (BETA) was assayed by examining clonidine (CLO)-induced hypoactivity in adult malnourished rats at perinatal age. As previously described, chronic restraint did not attenuate the hypoactivity elicited by CLO in malnourished rats, although chronic restraint did have such an effect on motor activity in control animals. MOR and BETA administration prior to each restraint session induced subsensitivity of alpha2-adrenoceptors in malnourished rats as determined by a blunted response to clonidine challenge. An injection of naloxone (NAL) prior to BETA before each stress session fully antagonized the subsensitivity to clonidine observed in malnourished animals. A possible deficiency in the functional role of the opiate system in the process of adaptation to chronic stress in perinatal malnourished rats is suggested.

Adrenergic alpha-Agonists↗
PubMed1998

The role of Ki67 proliferation assessment in predicting local control in bladder cancer patients treated by radical radiation therapy.

PURPOSE: To assess whether tumour proliferation as measured by Ki67 immunostaining has any predictive value for local control in bladder cancer patients treated by radiotherapy. PATIENTS AND METHODS: Fifty-five patients suffering from infiltrating bladder carcinoma recommended for radical radiotherapy (66 Gy/6-7 weeks) were included in this study. Paraffin-embedded pre-treatment tumour sections were stained with the Ki67 antibody. The percentage of Ki67-positive nuclei was correlated with established prognostic factors, local control and survival. RESULTS: The Ki67 index was not related to local control in our patients when the median was selected as the cut-off value. Patients with tumours with a very low (<27%) Ki67 index had better local control at 5 years (69%) than patients with tumours with greater (>27%) Ki67 expression indices (31.5%) (P<0.05; log-rank test). CONCLUSIONS: Ki67 immunostaining was a feasible method to estimate tumour proliferation. Patients with very low proliferating tumours seemed to achieve better local control after fractionated radiotherapy compared to other patients. Further studies are needed with a greater number of patients to accurately define the role of Ki67 expression in predicting tumour repopulation during fractionated radiotherapy.

Biomarkers, Tumor↗
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

Tirapazamine-cisplatin: the synergy.

Tirapazamine is a novel bioreductive agent with selective cytotoxicity against hypoxic tumour cells. Synergy with cisplatin and other chemotherapeutic agents has been shown in preclinical trials. Pharmacokinetic studies of tirapazamine have revealed that exposure increases with dose over the range of 18-450 mg m(-2) for a single dose and of 9-390 mg m(-2) for multiple doses. Plasma clearance is high. Tirapazamine has been clinically tested in combination with cisplatin at escalating doses in a phase I trial and at therapeutic doses in three separate phase II trials in patients with advanced non-small-cell lung cancer (NSCLC) in 11 study centres. Limiting toxicity for tirapazamine at an intravenous dose of 390 mg m(-2) was acute, reversible hearing loss. Other frequently observed side-effects included muscle cramping and gastrointestinal symptoms. Tirapazamine did not cause myelosuppression, and no toxic deaths were reported in these trials. The anti-tumour efficacy against previously untreated, advanced NSCLC was evaluated by cumulative intent-to-treat analysis of 132 patients. The objective response rate (confirmed by two independent measurements) was 25% [confidence interval (CI) 17.8-33.33], with a median survival of 38.9 weeks (CI 29.4-49.9). The efficacy of tirapazamine plus cisplatin shown in these trials was better than that of historical controls with cisplatin monotherapy. Two large-scale international trials have been conducted, involving more than 70 centres, to confirm these results. The CATAPULT I trial compares tirapazamine plus cisplatin with cisplatin and has finished accrual with 446 patients. The CATAPULT II trial, which is comparing tirapazamine plus cisplatin with etoposide plus cisplatin, had enrolled 550 patients by June 1997. Follow-up is ongoing. Tirapazamine is the promising first drug from a new class of cytotoxic agents with a novel mechanism of action. It can be effectively combined with cisplatin, and possibly with other agents, because of its safety profile and lack of overlapping dose-limiting toxicity, such as myelosuppression. The combination of tirapazamine and cisplatin appears to be safe and effective in the treatment of NSCLC.

Antineoplastic Agents↗
PubMed1998

Brain Abscesses of Ear, Nose, and Throat Origin: Comparison between Otogenic and Sinogenic Etiologies.

This retrospective study analyzed 29 cerebral abscesses of ear, nose, and throat (ENT) origin. The mean follow-up of patients was 37 months. ENT etiologies included 45% otitis media (n = 13), 48% sinusitis (n = 14), and 7% ethmoidal sinus tumors (n = 2). Thirty-eight percent (n = 5) of otogenic abscesses occurred within 15 days after a mastoidectomy. Sinogenic abscesses were never due to surgery but were associated in 31% of cases (n = 5) with anterior skull base defects. The main locations of otogenic abscesses were the temporal lobe (54%; n = 7) and the cerebellum (23%; n = 3), whereas sinogenic abscesses were located in the frontal lobe in 75% of cases (n = 12). Because of this location, sinogenic abscesses were less symptomatic than otogenic ones and had greater size and encapsulation at the time of diagnosis. Thus, they required longer antibiotic treatment (p = 0.05) and more numerous surgical drainages (p = 0.02). Bacteriologic abscesses samples were positive in 90% of cases. Bacteria found in brain abscesses were different from the ones found in ENT samples in 62% of cases. Thus, the results of ENT bacteriologic samples were not helpful for choosing adequate antibiotic agents in case of negative brain abscess samples. Although mortality was not significantly higher in otogenic abscesses (31%; n = 4) than in sinogenic ones (6%; n = 1, p = 0.08), otogenic abscesses appeared more threatening. Indeed, they represented 80% (n = 4) of lethal cases and encompassed more clinical or radiological prognosis pejorative factors than sinogenic ones (p = 0.006). In conclusion, higher danger of otogenic abscesses mainly resulted both from their temporal or cerebellous locations and from the bacteria that were more frequently resistant to antibiotics.

Journal Article↗
PubMed1998

Tuberculoma of the cavernous sinus: case report.

OBJECTIVE AND IMPORTANCE: The cavernous sinus is an exceptional location for intracranial tuberculomas. A rapid diagnosis, based on pathological findings, improves the prognosis. CLINICAL PRESENTATION: A case of left cavernous sinus tuberculoma, revealed by frontal headaches and ipsilateral palsies of Cranial Nerves III and V, in a 48-year-old patient is reported. The lesion mimicked an aggressive meningioma in radiological examinations. INTERVENTION: The lesion was excised through a subtemporal approach. The diagnosis was based on the pathological examination of the mass. Postoperative antituberculous chemotherapy completed the treatment. Neurological symptoms regressed rapidly. CONCLUSION: Although the incidence of intracranial tuberculomas is decreasing in developed countries, a high index of suspicion must be maintained for the diagnosis of intracranial masses in the presence of risk factors for tuberculosis.

Antitubercular Agents↗
PubMed1998

Intracranial berry aneurysms: angiographic and clinical results after endovascular treatment.

PURPOSE: To determine the types of aneurysm that may be treated endovascularly with platinum detachable coils. MATERIALS AND METHODS: Two hundred eight patients with 236 intracranial berry aneurysms underwent endovascular coil embolization; 150 patients had subarachnoid hemorrhage at the time of presentation. RESULTS: Treatment was performed in 182 patients with 203 (86%) aneurysms (86%). Follow-up angiograms were obtained at 3 months in 160 cases of aneurysm. A second procedure was performed in 18 (11%) of these cases, and a third was performed in one case. Final follow-up results in 152 aneurysms demonstrated total occlusion in 123 (81%) cases, subtotal occlusion in 26 (17%) cases, and incomplete occlusion in three (2%) cases. All patients with subtotally occluded aneurysm were scheduled for later angiographic follow-up and any indicated repeat treatment. Technique-related morbidity rate was 4% (seven patients with permanent neurologic deficits due to clotting). Technique-related mortality rate was 2% (perioperative rupture in two, hematoma due to urokinase perfusion in one, rebleeding of the initial hematoma after excessive uncontrolled anticoagulation in one). Rebleeding occurred in one patient after incomplete occlusion. CONCLUSION: Endovascular coil embolization seems to be a reliable technique, with good anatomic and clinical results, that provides protection against rebleeding of ruptured aneurysms.

Aneurysm, Ruptured↗
PubMed1998

Simulating individual word identification thresholds and errors in the fragmentation task.

This article presents a large-scale study that collected word identification thresholds and errors in the fragmentation task for all four-letter French words. In the first part of this article, we identify some of the variables (e.g., word frequency, neighborhood size, letter confusability) that affect performance in the fragmentation task. In the second part, we analyze individual response performance and identify different response strategies. We demonstrate that the interactive activation model can account for individual response strategies by adapting two of its original parameters: word-letter feedback and letter-word inhibition. In the third part, we demonstrate that the adaptation of the interactive activation model to the fragmentation task makes it possible to successfully simulate a facilitatory frequency effect on identification thresholds, an inhibitory neighborhood size effect on error rates, and an inhibitory letter confusability effect on identification thresholds. When the task-specific processes of the fragmentation task are specified and individual response strategies are considered, the interactive activation model provides a parsimonious architecture for modeling the task-independent processes involved in word perception.

Attention↗
PubMed1998

KI67 proliferation index in tumors of the upper urinary tract as related to established prognostic factors and long-term survival.

OBJECTIVE: Nephroureterectomy is the standard treatment for tumors of the renal pelvis and ureter. Conservative management or indication of adjuvant treatment in these neoplasms is based mainly in histological grade and stage. The aim of this study is to assess the relation of Ki67 index with other established prognostic factors and to define its predictive value for long term survival, which could be useful in selecting the best treatment for each individual case. METHODS: 81 patients with urothelial tumors of the renal pelvis and ureter, diagnosed and treated between 1975 and 1993, comprised the present study. Ki67 immunostaining was performed in paraffin-embedded tissue. A cut-off limit of 20% was chosen. Tumor location, histological grade, histological pattern, local (T), nodal (N), vascular and perineural invasion and stage (TNM) were assessed in relation to the proliferation index and as prognostic criteria for survival in both univariate and multivariate analysis. RESULTS: The Ki67 proliferation index was found to be related to grade (p < 0.001), T (T0 vs T1-4; p < 0.01), N (p < 0.038), TNM categories (stage 0 vs I-IV; p < 0.048) and perineural invasion (p < 0.01). There was a marginal relation to vascular invasion (p < 0.11). Survival was better for the patients with low proliferating tumors (90%) than for high proliferating ones (67%) (p < 0.02). In the multivariate analysis only T stage was statistically significant (p < 0.01) but a highly suggestive trend was found for the Ki67 index (p < 0.07). CONCLUSIONS: Tumor proliferation assessed by Ki67 immunostaining is related to the progression of the disease and proved to be of predictive value for long-term survival in tumors of the renal pelvis and ureter. The Ki67 index is able to detect high-risk patients that could not be cured by radical surgery alone, raising the need for some type of aduvant treatment in these cases. The treatment predictive effect observed in low grade-low stage cases suggests its possible utility in patients managed conservatively.

Adult↗
PubMed1998

Hearing restoration in posterior fossa tumors.

OBJECTIVE: This study aimed to assess the results of hearing restoration with a cochlear or a brainstem implant in posterior fossa tumors. PATIENTS: Six patients were selected. Two patients with an acoustic neuroma in the only-hearing ear (cases 1 and 2), one patient with a posterior fossa meningioma (case 3), one patient with bilateral facial neuroma (case 4), and two patients with bilateral acoustic neuroma (cases 5 and 6) participated. INTERVENTION: In cases 1 and 2, the patients had a cochlear implant inserted on the only-hearing ear opposite the acoustic neuroma. In case 3, the patient presented with total deafness on the left side and a 10-mm meningioma on the right side. A cochlear implantation was performed after removal of the meningioma on the right side. In case 4, the patient was operated on on both sides with bilateral postoperative deafness. A cochlear implantation was performed on the better hearing ear. In cases 5 and 6, patients underwent an auditory brainstem implantation after the exeresis of the second tumor. RESULTS: Promontory test results were positive for patients 1, 2, 3, and 4. After implantation, patients 1, 2, 3, and 4 scored 98%, 13%, 70%, and 30%, respectively, in open-set sentence recognition tests, whereas patients 5 and 6 scored 0% and 20%, respectively. CONCLUSIONS: In case of nonfunctional cochlear nerve, in acoustic neuroma, either bilateral and in the only-hearing ear, promontory test should be performed. If positive results, a cochlear implantation should be performed, because successful results could be expected. Overall results of cochlear implantation on speech discrimination are better than those obtained with a brainstem implant.

Adolescent↗
PubMed1998

[Intra-labyrinthine schwannomas: a report of two cases].

Intralabyrinthine schwannomas are rare tumors of vestibule, cochlea, semicircular canals, or some combination of these three. In the past, they have been found at autopsy or as incidental finding at surgery. Since the advent of magnetic resonance imaging (MRI) with intravenous gadolinium contrast, the preoperative diagnosis is possible. We report two cases of intralabyrinthine schwannoma: one case of intralabyrinthine schwannoma extended into the internal auditory canal (IAC), a second case of tumor restricted to the vestibule. No characteristic clinical presentation of this tumor is reported in the literature. In patients with vestibular weakness (vertigo and no response of caloric testing), MRI with gadolinium contrast can make the diagnosis of intravestibular tumor. In patients with the more common IAC acoustic neuromas, MRI can demonstrate extension of tumor into the labyrinth; diagnosing this extension preoperatively is important to plan surgical treatment.

Adult↗
PubMed1998

[Management of intracanalicular acoustic neurinoma].

Between 1991 and 1996, 35 patients had an intracanalicular tumor: 26 patients were operated via middle cranial fossa approach (MFA: 23 cases) or translabyrinthine approach (TL: 3 cases), 9 cases were supervised by audiovestibular testing and MRI. For the operated patients through MFA the functional hearing (pure tone loss < 50 dB and 100% vocal discrimination) was preserved in 47.8% of cases, facial function was grade I and II in 83% of cases and grade III in 17% of cases. One recurrence was noted and reoperated by TL. For the TL operated patients, the postoperative facial function was normal (grade I) in all cases. Among the 9 supervised cases for reasons of age (more than 60 years), or the tumoral size (< than 5 mm): the tumor in 3 cases did not increase in size, 5 cases increased by 1 mm/year and 1 case increased 1 cm/year (and must be operated). These results show the importance of the middle cranial fossa approach for excision of intracanalicular neuromas and supervising patients with the same tumor according to age, and tumoral size.

Adolescent↗
PubMed1997

Effect of interleukin-4 on allergen-induced arachidonic acid metabolism of rat peritoneal macrophages during immediate hypersensitivity reactions.

The aim of this study was to investigate the [3H]arachidonic acid metabolism of rat peritoneal macrophages, induced by allergen (ovalbumin) and the impact of interleukin-4 on this process. We established that ovalbumin induces an increase of [3H]arachidonic acid mobilisation from membrane lipids and of [3H]arachidonic acid catabolism, principally by the 5-lipoxygenase pathway, when the macrophages are sensitized and when serum is present. The allergen effect is not modified by the presence of interleukin-4 in the culture medium of macrophages 15 h before the allergen challenge. We also showed that, whereas the basal [3H]arachidonic acid metabolism of macrophages from control and actively sensitized rats is not different, interleukin-4 increases the [3H]arachidonic acid mobilisation and catabolism by cyclooxygenase and 5-lipoxygenase pathways in macrophages from control rats although it does not in macrophages from actively sensitized rats. In macrophages from control rats, the interleukin-4 effect is diminished by the addition of IgEs to their culture medium. In summary, interleukin-4 has an enhancer effect on the macrophage arachidonic acid catabolism that depends on the sensitization condition of the cell but that has no consequences on the further increased arachidonic acid metabolism induced by the allergen.

Allergens↗
PubMed1997

Overexpression of p53 in transitional cell carcinoma of the renal pelvis and ureter. Relation to tumor proliferation and survival.

BACKGROUND: Clinical management of patients with tumors of the upper urinary tract is based mainly on histologic grade and stage of the tumors. In recent years, tumor proliferation has also proved to be an important factor in determining the prognosis of these and other transitional cell tumors. The aim of this study was to assess the role of p53 in regulating cell proliferation and tumor progression and to define its value in predicting the long term survival of patients with these tumors. Such information could be of use in selecting treatment in individual cases. METHODS: Eighty-three patients with urothelial tumors of the renal pelvis and ureter diagnosed and treated between 1975 and 1993 were included in this study. p53 immunostaining was performed on paraffin embedded tissue. Tumor location, histologic grade, histologic pattern, tumor proliferation by Ki-67, local (T classification), lymph node (N classification), vascular and perineural invasion, and clinical stage (TNM) were assessed in relation to p53 overexpression (Mann-Whitney U test and analysis of variance comparisons) and as prognostic factors for survival in both univariate analysis (log rank test) and multivariate analysis (Cox proportional hazards model). RESULTS: Overexpression of p53 was related to tumor proliferation as assessed by Ki-67 (P < 0.01), T classification (Ta vs. T1-4; P < 0.01), N classification (P < 0.054), and TNM staging (Stage 0 vs. I-IV; P < 0.01). There was also a statistically significant relation to vascular (P < 0.002) and perineural invasion (P < 0.04). Fifteen-year actuarial survival for the whole group was 75%. Patients having tumors with low p53 overexpression (< 30% of stained nuclei) had a better survival rate (88%) than those having tumors with high (> 30%) p53 overexpression (65%) (P < 0.02), and this effect reached statistical significance with high grade (P < 0.02) and infiltrating tumors (P < 0.04). Patients with low p53 and Ki-67 expression had a 15-year survival rate of 100%; in contrast, patients with overexpression of both markers had a 15-year survival rate of 61% (P < 0.003). In a multivariate analysis, only T classification (P < 0.001) and p53-Ki-67 expression (P < 0.026) were statistically significant. CONCLUSIONS: Overexpression of p53 is related to increased tumor proliferation and disease progression and is of value in determining the long term survival of patients with tumors of the renal pelvis and ureter. p53 immunostaining can be used to distinguish low risk patients in the theoretically unfavorable high grade, high stage group, and when used together with Ki-67 index, it is a predictive factor for survival.

Adult↗
PubMed1997

Second malignant neoplasms in patients treated on SIOP Wilms tumour studies and trials 1, 2, 5, and 6.

The incidence of second malignant neoplasms (SMNs) was investigated among 1,988 patients with complete data, enrolled in the SIOP Wilms tumor trials and studies 1, 2, 5, and 6, treated between September 1971 and October 1987. By the end of 1992, eight SMNs were documented, whereas only 1.3 were expected (standardized incidence ratio [SIR] = 4.15; 95% CI = 1.79, 8.17). The risk increases in the first 10 years from diagnosis, while no apparent excess of risk is observed in the subsequent periods. This finding however is difficult to interpretdue to the low statistical power. The cumulative incidence of a second cancer observed at 15 years after Wilms tumor diagnosis was 0.65%. Six SMNs were registered in the cohort of patients treated in the SIOP studies 1, 2 and 5 (999 cases) compared to the two cases observed in the SIOP6 cohort (989 cases). If the suggested reduced incidence of second cancers between SIOP1-5 and SIOP6 patient cohorts is confirmed by longer follow-up, it might reflect changes in the treatment protocols.

Adolescent↗
PubMed1997

Syringomyelia and Arnold Chiari in scoliosis initially classified as idiopathic: experience with 25 patients.

The authors analysed the clinical and radiological findings and the surgical management of 25 patients admitted for scoliosis classified as idiopathic at first presentation, but in fact associated with spinal cord and/or brain stem anomalies. Twenty patients had syringomyelia, 19 had Chiari malformation. Scoliosis was the only presenting symptom when all these patients were referred to the orthopaedic surgeon. On examination, five patients had normal neurological findings, while the others showed very mild neurological deficits. The diagnosis of syringomyelia and Chiari malformation was established by MRI, which is the best form of neuroradiological examination for discovering spinal abnormalities. Neurosurgical treatment is strongly recommended as the first step in the management of "pseudo" idiopathic scoliosis.

Adult↗