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71.
PURPOSE: To analyze the management and clinical outcome of patients treated for a first isolated local recurrence of soft tissue sarcomas (trunk or extremities) and to identify prognosis factors. METHODS AND MATERIAL: Between 1980 and 1999, 83 adult patients were included in the study. Mean age was 61 years. Mean tumor size was 6 cm. Most sarcomas were located in extremities (n=74), were deep (n=60), and proximal (n=53); 30 involved nerves or vessels. Histologic subtypes were mainly grade 2 (42%) or 3 (36%) histiocytofibrosarcomas (49%) and liposarcomas (20%). Surgical treatment of recurrences consisted in wide excision (29 cases), marginal resection (43 cases), 5 patients requiring amputation. Final results were R0 (n=33), R1 (n=47) or R2 (n=3) resection. Besides surgery, 6 patients received neo-adjuvant and 7 others adjuvant chemotherapy. Twenty three patients received post-operative external beam radiotherapy (EBRT) (mean dose 55 Gy) and 26 interstitial 192Ir low dose rate brachytherapy (BCT) (mean dose 45 Gy for BCT alone, 22 Gy when associated with EBRT), 19 patients being re-irradiated. RESULTS: Mean follow up was 13 years. Thirty-seven (45%) patients relapsed, 62% of whom presenting an isolated local recurrence. Nineteen patients developed distant metastases. Multivariate analysis showed only tumor depth (P=0.05) and re-resection for primary R1 resection (P=0.018) being independent prognosis factors for tumor control, radiotherapy (EBRT and/or BCT) being significant in univariate analysis (P=0.05). Overall survival rate was 73%, 54%, and 47% at, respectively, 3.5 and 10 years, and was 65%, 35% and 32% after a further local recurrence. Multivariate analysis showed trunk (P=0.0001) or inferior extremity locations (P=0.023), symptomatic (P=0.001), high grade (P=0.01), deep (P=0.01) tumors, and the occurrence of a further local failure (P=0.004) as unfavorable characteristics for overall survival. CONCLUSIONS: A first isolated local recurrence of STS increases mainly the risk of a subsequent local relapse. Quality of local treatment is decisive. When a conservative treatment is feasible, it should combine surgical resection and radiotherapy, BCT being the best suited in previously irradiated patients. Efforts have to be pursued to increase quality of the treatment of primary tumors, at best performed in centers that have expertise in this field.  相似文献   
72.
PURPOSE: The purpose of this research was to evaluate whether baseline health-related quality of life (HRQOL) parameters are prognostic factors for survival in locally advanced breast cancer patients. Although the literature highlights the important role of HRQOL parameters in predicting survival in advanced metastatic disease, little evidence exists for earlier stages. PATIENTS AND METHODS: The overall sample consisted of 448 patients randomly assigned to receive cyclophosphamide, epirubicin, and fluorouracil versus epirubicin, cyclophosphamide, and granulocyte colony-stimulating factor. Patients were enrolled in 12 countries. HRQOL baseline scores were assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30. The Cox proportional hazards regression model was used for both univariate and multivariate analyses of survival. In addition, a bootstrap resampling technique was used to assess the stability of the outcomes. Bootstrap results were then applied for model averaging purposes as a means to account for the observed model selection uncertainty. RESULTS: The final multivariate model retained inflammatory breast cancer (T4d) as the only factor predicting overall survival (OS) with a hazard ratio of 1.375 (95% CI, 1.027 to 1.840; P =.03). The presence of inflammatory breast cancer lowers the median survival time from 6.6 to 4.2 years (36% reduction). None of the preselected HRQOL variables were prognostic for OS or disease-free survival, in either the univariate or multivariate analysis. CONCLUSION: Our findings suggest that baseline HRQOL parameters have no prognostic value in a nonmetastatic breast cancer population.  相似文献   
73.
The ability of three Lactobacillus strains to inhibit the adhesion and growth of naturally occurring uropathogens on silicone rubber was investigated in human urine. The importance of biosurfactant production by Lactobacillus in discouraging uropathogen growth was determined in relation to the binding affinities of the lactobacilli for silicone rubber. L. fermentum B54 markedly inhibited uropathogen growth on the silicone rubber disks after 8 days for all five men included in the study, albeit to various extents ranging from 77% to 100%. In urine from women, however, this inhibition was less clear, as it was absent for two of the four women participating in this study. L. casei rhamnosus 36 completely discouraged uropathogen growth on the disks after 8 days for three of the four women, whereas its effect in urine from men was less pronounced (inhibition ranged from 48% to 100% and was absent for one man). L. casei rhamnosus ATCC 7469T was the least inhibitory Lactobacillus strain tested and inhibition was absent for a number of both male and female participants, possibly as a result of the low binding affinity of this strain for silicone rubber and of its inability to release biosurfactants. We conclude that the inhibition of uropathogen growth is dependent on the Lactobacillus strain involved, and for L. fermentum B54 it was demonstrated to be sex-related. Hence, inhibition must be considered a multifactorial process.  相似文献   
74.
In the present paper the treatment of advanced and metastatic soft tissue sarcoma is reviewed with the primary emphasis on chemotherapy. One of the major advances in the treatment of soft tissue sarcomas is their treatment by multidisciplinary teams in specialized centers. Despite optimal local treatment of the primary tumor, disseminated disease will develop in many patients. Consequently, chemotherapy has been extensively studied but, unfortunately, the responsiveness of these tumors to chemotherapy has been disappointingly low. Doxorubicin and ifosfamide appear to be the most effective drugs — the latter with a somewhat higher toxicity at effective dosages. Other drugs with some first line activity are dacarbazine, liposomal doxorubicin and possibly trabectedin (ET-743). Imatinib is very effective in gastrointestinal stromal tumors (GIST) where it is now the treatment of choice. The combination of doxorubicin and ifosfamide increases the response rate without affecting overall survival. For these reasons, single agent doxorubicin is, in many centers, considered the standard treatment for advanced soft tissue sarcoma, and combination chemotherapy should be reserved for special subgroups of patients such as young patients with chemosensitive tumors. Chemotherapy for patients with advanced and metastatic soft tissue sarcoma is inadequate at present and new drugs are desperately needed. Fortunately, exciting new drugs are under development and hopefully they will improve the treatment of patients with this disease.  相似文献   
75.
The incidence and characteristics of foramen thyroideum (FT) in embryonic and/or fetal larynges have not been established. In the present study, 90 adult larynges and 53 embryonic-fetal larynges were studied. The incidence of FT during the embryonic-fetal period (57%) was statistically different from the adult period (31%) (P = 0.005). All the FT found in the adult period contained vessels and/or nerves, while in the embryonic and fetal period only 63% presented neurovascular elements (P < 0.001). The origin of FT in the embryonic period and its persistence during adult life is discussed.  相似文献   
76.
A number of studies have shown that chemical stimulation (using N-methyl-D-aspartate (NMDA) infusions) or electrical stimulation of the ventral hippocampus (VH) elicits locomotor activation and sustained increases in nucleus accumbens (NAc) dopamine (DA) levels in rodents. How DA neurotransmission in NAc is involved in these effects has also been well established. However, the modulatory role of the DA receptors located in VH is not yet fully understood. The purpose of this study was to characterize the role played by VH D1 and D2 subtype receptors in both the locomotor activation and NAc DA increases induced by NMDA stimulation of the VH. This was assessed by studying how retrodialysis application of NMDA (50 mM, 10 min) affects motor activity and NAc DA levels during simultaneous retrodialysis administration of the D1/D5 receptor antagonist SCH 23390 (100 and 250 microM, 60 min) or the D2 receptor antagonist raclopride (100 and 250 microM, 60 min). SCH 23390 attenuated or completely abolished NMDA-evoked locomotor activation and the concurrent increase in NAc DA levels. On the other hand, raclopride was initially able to attenuate the effects of VH NMDA stimulation. However, in the last phase of the experiments, animals showed an important increase in clonic seizure activity with a simultaneous and dramatic increase in NAc DA levels. Our results show that the NMDA receptor-mediated effects in the VH require both D1 and, probably, D2 receptors and suggest that DA in VH strongly modulates the excitatory outputs from this brain area.  相似文献   
77.
78.
Conditioned place aversion in rats has face validity as a measure of the aversive stimulus effects of opiate withdrawal that reflects an important motivational component of opiate dependence. The purpose of the present study was to validate conditioned place aversion as sensitive to medications that will alleviate the aversive stimulus effects of opiate withdrawal in humans, and to extend this model to the exploration of the neuropharmacological basis of the motivational effects of opiate withdrawal. Male Sprague-Dawley rats were implanted with two subcutaneous morphine pellets and 5 days later began place conditioning training following subcutaneous administration of a low dose of naloxone. Animals were subjected to three pairings of a low dose of naloxone (15 microg/kg, s.c.) to one arm of a three-chambered place conditioning apparatus. Buprenorphine administered prior to each pairing dose-dependently blocked the place aversion produced by precipitated opiate withdrawal. A corticotropin-releasing factor-1 (CRF1) receptor antagonist (antalarmin) also reversed the place aversion produced by precipitated opiate withdrawal. Antalarmin did not produce a place preference or place aversion by itself in morphine-dependent rats. No effect was observed with pretreatment of the dopamine partial agonist terguride or the selective serotonin reuptake inhibitor fluoxetine. Also, chronic pretreatment with acamprosate (a glutamate receptor modulator used to prevent relapse in alcohol dependence) did not alter naloxone-induced place aversion. Buprenorphine by itself in dependent rats produced a mild place preference at low doses and a mild place aversion at higher doses. These results suggest that buprenorphine blocks the aversive stimulus effects of precipitated opiate withdrawal in rats and provides some validity for the use of place conditioning as a measure that is sensitive to potential opiate-dependence medications. In addition, these results suggest that CRF1 antagonists can block the aversive stimulus effects of opiate withdrawal and may be potential therapeutic targets for opiate dependence.  相似文献   
79.
80.
PURPOSE: Whether salvage therapy in patients with advanced aggressive non-Hodgkin's lymphoma (NHL) in partial remission (PR) should consist of radiotherapy or autologous stem-cell transplantation (ASCT) is debatable. We evaluated the impact of radiotherapy on outcome in PR patients treated in four successive European Organization for Research and Treatment of Cancer trials for aggressive NHL. PATIENTS AND METHODS: Records of 974 patients (1980-1999) were reviewed regarding initial response, final outcome, and type and timing of salvage treatment. After 8 cycles of doxorubicin-based chemotherapy, 227 NHL patients were in PR and treated: 114 received involved field radiotherapy, 16 ASCT, 93 second-line chemotherapy, and 4 were operated. Overall survival (OS) and progression-free survival (PFS) after radiotherapy were estimated (Kaplan-Meier method) and compared with other treatments (log-rank). Impact on survival was evaluated by multivariate analysis (Cox proportional hazards model). RESULTS: The median PFS in PR patients was 4.2 years and 48% remained progression-free at 5 years. Half of the PR patients converted to a complete remission. After conversion, survival was comparable to patients directly in complete remission. Radiotherapy resulted in better OS and PFS compared with other treatments, especially in patients with low to intermediate International Prognostic Index score, bulky disease, or nodal disease only. Correction by multivariate analysis for prognostic factors such as stage, bulky disease, and number of extranodal locations showed that radiotherapy was clearly the most significant factor affecting both OS and PFS. CONCLUSION: This retrospective analysis demonstrates that radiotherapy can be effective for patients in PR after fully dosed chemotherapy; assessment in a randomized trial (radiotherapy vs. ASCT) is justified.  相似文献   
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