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PURPOSE: To determine demographic data and define prognostic factors for long-term outcome in patients presenting with high-grade osteosarcoma of bone with clinically detectable metastases at initial presentation. PATIENTS AND METHODS: Of 1,765 patients with newly diagnosed, previously untreated high-grade osteosarcomas of bone registered in the neoadjuvant Cooperative Osteosarcoma Study Group studies before 1999, 202 patients (11.4%) had proven metastases at diagnosis and therefore were enrolled onto an analysis of demographic-, tumor-, and treatment-related variables, response, and survival. The intended therapeutic strategy included pre- and postoperative multiagent chemotherapy as well as aggressive surgery of all resectable lesions. RESULTS: With a median follow-up of 1.9 years (5.5 years for survivors), 60 patients were alive, 37 of whom were in continuously complete surgical remission. Actuarial overall survival rates at 5 and 10 (same value for 15) years were 29% (SE = 3%) and 24% (SE = 4%), respectively. In univariate analysis, survival was significantly correlated with patient age, site of the primary tumor, number and location of metastases, number of involved organ systems, histologic response of the primary tumor to preoperative chemotherapy, and completeness and time point of surgical resection of all tumor sites. However, after multivariate Cox regression analysis, only multiple metastases at diagnosis (relative hazard rate [RHR] = 2.3) and macroscopically incomplete surgical resection (RHR = 2.4) remained significantly associated with inferior outcomes. CONCLUSION: The number of metastases at diagnosis and the completeness of surgical resection of all clinically detected tumor sites are of independent prognostic value in patients with proven primary metastatic osteosarcoma.  相似文献   
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PURPOSE: To evaluate the impact of patient, tumor, and treatment-related factors on outcome in unselected patients with recurrent osteosarcoma. PATIENTS AND METHODS: Five hundred seventy-six consecutive patients who had achieved a first complete surgical remission (CR) during combined-modality therapy on neoadjuvant Cooperative Osteosarcoma Study Group (COSS) protocols and then developed recurrent osteosarcoma were analyzed (median time from biopsy to relapse, 1.6 years; range, 0.1 to 14.3 years). There were 501 patients with metastases, 44 with local recurrences, and 31 with both. Metastases involved lungs (469 patients), bones (90 patients), and/or other sites (54 patients). RESULTS: After a median follow-up of 1.2 years for all patients and 4.2 years for survivors, actuarial overall survival (OS) rates at 2, 5, and 10 years were 0.38, 0.23, and 0.18, respectively. Five-year OS was 0.39 for 339 patients with and 0.00 for 229 patients without a second surgical CR (P < .0001). A long time to relapse, a solitary lesion, and, in the case of pulmonary metastases, unilateral disease and the absence of pleural disruption, were of positive prognostic value in uni- and multivariate analyses, as were a second surgical CR and the use of second-line chemotherapy. Radiotherapy was associated with moderately prolonged survival in patients without a second CR. The very limited prognostic differences associated with the use of second-line chemotherapy appeared to be more pronounced with polychemotherapy. CONCLUSION: Time to relapse and tumor burden correlate with postrelapse outcome in osteosarcoma. Complete surgery is an essential component of curative second-line therapy. Chemotherapy, particularly chemotherapy with more than one agent, may contribute to limited improvements in outcome.  相似文献   
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Cervical pregnancy (CP) is a rare and life-threatening ectopic pregnancy characterized by implantation of the fertilized ovum into the cervix, whereas exocervical pregnancy is an extremely rare CP with implantation of the fertilized ovum on the exocervix. Possible causative factors of CP such as tubal dysfunction, impaired sperm motility, previous uterine surgery, or the use of intrauterine device were not clearly associated with the development of CP until now. Diagnosis of CP is usually established by ultrasonography and by beta-human chorionic gonadotropin serum tests, but definitive diagnosis is by histologic examination. Current treatment strategies of CP, which were described in some reports, involve: medical treatment with methotrexate, surgical removal of ectopic trophoblastic tissues, cervical cerclage and vaginal packing, ligation of descending branches of uterine arteries or hypogastric arteries, and unilateral internal iliac artery embolization. We report a case of exocervical pregnancy contemporary to intrauterine device normally inserted, diagnosed by colposcopy, beta-human chorionic gonadotropin, and histology, and treated by a local excision without using methotrexate chemotherapy.  相似文献   
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Delamination is one of the most critical failure modes of a PV module during service lifetime. Delamination within a backsheet primarily imposes a safety risk, but may also accelerate various other PV module degradation modes. The main aim of this paper is to present a peel test set-up, which is more practical in sample preparation and execution than the width-tapered cantilever beam test and overcomes some issues of standard peel tests like the influence of sample geometry and energy dissipation through deformation on the peel test results. The best results with respect to accuracy and effort were achieved by using a 180° peel geometry where an additional adhesive tape is applied to the peel arm in order to avoid plastic deformation or breakage. The additional support of the adhesive tape leads to comparable peel strength values without any influence of the plastic deformation behavior of the peel arms with different thickness.  相似文献   
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