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81.
Factors affecting survival in maxillary sinus cancer.   总被引:4,自引:0,他引:4  
PURPOSE: The study goal was to determine survival parameters and clinical factors influencing survival for maxillary sinus malignancies. METHODS: Cases of maxillary sinus malignancy for the time period 1988 to 1998 were extracted from the Surveillance, Epidemiology and End Results database. Cases with distant metastatic disease at presentation were excluded. Clinical information, including tumor histology, grade and stage, and extent of surgery and radiation therapy, were determined. Kaplan-Meier survival and Cox proportional hazards analyses were conducted to determine the influence of these factors on overall survival. RESULTS: The study sample was composed of 650 patients with maxillary sinus cancer (mean age, 64 years; male-to-female ratio, 3:2). The most common histology was squamous cell carcinoma (61.7%), followed by adenoid cystic carcinoma (9.8%). The overall mean (median) survival was 52 months (25 months), and 77.5% and 7.4% of patients presented with advanced (T3/T4) disease or cervical metastasis, respectively. Radiation therapy was administered in 441 patients (67.9%) and significantly improved survival mainly for those with T4 lesions. On multivariate analysis, increasing age, T stage, N stage, and tumor grade independently predicted poorer survival, whereas gender did not. Adenoid cystic carcinoma exhibited a significantly improved overall survival (P <.001). CONCLUSIONS: Survival for patients with maxillary sinus cancer is determined not only by TNM staging but also by tumor histology and grade. TNM staging effectively stratifies patients according to survival. Radiation therapy significantly improves survival for those with T4 lesions.  相似文献   
82.
Stenosis of the hypopharyngo-oesophageal junction can be a rare complication of laryngectomy and/or partial pharyngectomy and makes the insertion of voice prosthesis extremely difficult. This study describes the authors’ experiences gained by endoscopic balloon-catheter dilatation of hypopharyngo-oesophageal stenoses prior to implantation of voice prostheses in four cases. In two patients a single balloon-catheter dilatation resulted in wide enough pharyngo-oesophageal lumen on the long run. The average prosthesis wearing-times were 6.8 months in case 1 and 4.6 months in case 2, corresponding to the published literature data. In case 3, repeated dilatation of the pharyngo-oesophageal transition had proved to be unsuccessful despite taking every effort with the endoscopic balloon-catheter method. Having excised the stenotic segment, reconstruction with pectoralis major myocutaneous flap (PMMF) was indicated. Eighteen months later, a repeated restenosis was observed and a free jejunal flap needed to be performed as a final solution. In case 4, the insertion was carried out into a previously dilated jejunal free flap, which became gradually ischemic and stenotic since the major head-and neck procedure was carried out that resulted in prosthesis rejection after just 1 week. The authors emphasize that correct indication of pedicled and free flaps in head and neck reconstruction is a prerequisite from the aspect of prevention of pharyngo-oesophageal strictures. Endoscopic balloon-catheter dilatation is a safe and established method for dilatating hypopharyngo-oesophageal stenoses of different origin. The procedure provides maximum patient benefit with minimal trauma and morbidity; moreover, facilitates insertion of voice prostheses. However, a single balloon-catheter dilatation cannot always result in wide enough oesophageal lumen on the long run (case 3). Insertion of a voice prosthesis into a previously dilated ischemic jejunal segment is challenging and avoidable due to risks of complications.  相似文献   
83.
Current treatment of acute stroke remains unsatisfactory. This review presents experimental and clinical data which suggest that mild induced hypothermia could be a potent and practicable neuroprotective treatment of acute ischaemic stroke and intracerebral haemorrhage. Hypothermia, if proven to be safe, effective and widely practicable in patients with acute stroke, could have an enormous positive impact on reducing the burden of stroke worldwide. Critical issues that will need to be considered in a well designed randomised controlled trial of induced hypothermia in acute stroke patients are discussed.  相似文献   
84.
Epiploic appendagitis and omental infarction: pitfalls and look-alikes   总被引:3,自引:0,他引:3  
Epiploic appendagitis and omental infarction are benign self-limiting conditions that are more frequent than generally assumed. Both disorders frequently mimic symptoms of an abdominal surgical emergency, often leading to clinical misdiagnosis of appendicitis or diverticulitis. Because a misdiagnosis can result in an unnecessary laparotomy, a correct diagnosis is of great importance. Ultrasound and computed tomography can be used to make a reliable diagnosis. This pictorial essay illustrates the various ultrasonographic and computed tomographic appearances of epiploic appendagitis and omental infarction and focuses on their radiologic differential diagnoses and pitfalls. Received: 22 February 2001/Accepted: 18 April 2001  相似文献   
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Ohne Zusammenfassung  相似文献   
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Optic nerve sheath meningiomas are by far the most common tumors of the optic nerve sheath. The diagnosis can be suspected in most cases from clinical findings and supported by the results of neuroimaging, obviating tissue biopsy in the majority of cases. Observation may be appropriate in patients with mild or no visual deficit or in whom visual loss is not progressing, whereas stereotactic fractionated radiation therapy has been demonstrated to improve or stabilize vision in progressive or advanced cases. Attempts at surgical excision, and even biopsy, of optic nerve sheath meningiomas are associated with a high risk of blindness and should be reserved for the rare case of an anteriorly located, primarily exophytic tumor with focal involvement of the dural sheath.  相似文献   
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