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61.
62.
There have been several recent reports in the literature to indicate that the risk of failure at the primary site following radiation therapy is greater in patients with a clinically positive neck as opposed to those with a clinically negative neck at diagnosis. This is an analysis of 526 patients with squamous cell carcinoma of the head and neck who were treated with irradiation alone to the primary lesion with curative intent. All patients had follow-up for at least 2 years and were evaluable for analysis of local control. For each site and T stage, no evidence was found to indicate that the primary lesions were controlled less often in patients whose necks were clinically positive than in those whose necks were clinically negative.  相似文献   
63.
Foreign body removal has been developed as a routine radiology department service. Techniques, indications and hazards are described.  相似文献   
64.
Hypopharyngeal carcinoma   总被引:1,自引:0,他引:1  
Opinion statement For more than 20 years, the policy at the University of Florida has been to treat patients with favorable stage T1-T2 pyriform sinus carcinoma by using radiation therapy alone, or with a planned neck dissection if advanced nodal disease is present. This approach usually leaves the patient with nearly normal swallowing and speech, and provides bilateral coverage of the regional neck and retropharyngeal lymphatics. More advanced lesions often are not controlled with radiation alone and are usually considered for partial or total laryngopharyngectomy if the patient is medically operable [1]. Radiation is usually administered postoperatively in this setting, unless the neck disease is thought to be unresectable, in which case preoperative radiation is given. Recent data have shown that adjuvant chemotherapy administered concomitantly with radiotherapy results in improved cure rates for patients with advanced disease compared with irradiation alone. Time-honored established guidelines are still used, although the edges have become blurred. Therefore, patients with larger primary tumors now may be considered for organ preservation treatment with irradiation and chemotherapy, reserving surgery for salvage situations. The subset of patients with advanced T4 pyriform sinus cancers (in whom cure with chemoradiation would likely result in tracheostomy and/or gastrostomy dependence) may be better served with elective surgery and postoperative irradiation. The definition of this subset of patients is unclear but probably includes patients with significant cartilage destruction and those who require pretreatment tracheostomy. The policy at the University of Florida is to treat essentially all pharyngeal wall cancers with external-beam irradiation alone.  相似文献   
65.
PURPOSE: To report long-term rates of tumor control after radiotherapy (RT) for carcinoma in situ (CIS) of the true vocal cords (TVC). A comprehensive literature review was performed, and outcomes with other modalities of treatment for CIS of the TVC were compared. METHODS AND MATERIALS: Thirty patients with CIS of the TVC were treated between July 1967 and May 1998 with curative intent using megavoltage RT. Most patients (28 of 30) were treated with cobalt-60 through small (usually 5 x 5 cm) fields. Median RT dose was 56.25 Gy (range, 56.25-75 Gy; mean dose, 59.15 Gy) at 2.25 Gy per fraction. One patient was treated for a synchronous head and neck primary malignancy with large fields to a total dose of 75 Gy at 1.8 Gy per fraction. Approximately two thirds of the patients (19 of 30) were referred for RT because of recurrence after at least one stripping procedure. RESULTS: With a mean follow-up of 7.1 years (range, 2-17 years), the 5-year rates of local control, local control with larynx preservation, and ultimate local control (including salvage surgery) were the following: 88%, 88%, and 100%, respectively. Invasive squamous cell carcinoma developed in three (10%) of the patients. Time to failure was 14 months, 34 months, and 48 months, respectively. All three patients were surgically salvaged with a total laryngectomy. Cause-specific survival at 5 years was 100%. There were no late complications. CONCLUSIONS: RT to approximately 60 Gy at 2.25 Gy per fraction using small (5 x 5 cm) fields produces excellent results with CIS of the TVC.  相似文献   
66.
PURPOSE: To report the outcome of patients with paraganglioma of the temporal bone treated with stereotactic radiosurgery at the University of Florida. METHODS AND MATERIALS: Between January 1997 and June 1999, five patients with paraganglioma of the temporal bone were treated with Linac-based stereotactic radiosurgery at the University of Florida. The ages of the three female and two male patients were between 40 and 88 years (median, 49 years). Four patients were treated at initial presentation, and one had recurrent disease. Treatment volumes ranged from 4.9 cm3 to 18.4 cm3, with a mean of 10.84 cm3. The dose applied to the margin of the tumor varied from 12.5 to 15 Gy (median, 15 Gy). The treatment dose was specified to the 80% isodose shell in two cases and to the 70% isodose shell in three cases. The median follow-up time was 27 months, ranging from 14 to 50 months. RESULTS: One of four previously untreated patients had a relapse at the primary tumor site. Treatment failure occurred at the field margin 6 months after radiosurgery; the patient was subsequently treated with fractionated stereotactic radiotherapy and at the time of analysis had no evidence of disease, 21 months after initiation of salvage therapy. The patient treated at the time of recurrence after conventional radiotherapy had a local recurrence 40 months after radiosurgery. At the time of this recurrence, the patient had biopsy-proven metastatic disease in two cervical lymph nodes, and no salvage therapy was performed. All patients were alive at the time of the analysis, one with disease present. Presenting symptoms improved in two patients and stabilized in one. The two patients who had local recurrence develop had worsening of their symptoms. One patient had a cranial nerve V palsy develop 6 months after treatment, which resolved after a few months. CONCLUSIONS: In this series, the results with stereotactic radiosurgery are discouraging compared with our results with conventional fractionated radiotherapy in patients with paraganglioma of the temporal bone.  相似文献   
67.
Carcinoma of the skin of the head and neck with perineural invasion.   总被引:2,自引:0,他引:2  
BACKGROUND: Perineural invasion is observed in a small subset of patients with carcinomas of the skin of the head and neck. METHODS: Review of the patient literature highlighting the University of Florida experience. RESULTS: Patients with early perineural invasion are asymptomatic, and the phenomenon is discovered only on pathologic examination of the excised lesion. These patients are defined as having "incidental" perineural invasion, and treatment with surgery followed by postoperative irradiation results in a cure rate of approximately 80%. Undiagnosed, the perineural carcinoma slowly progresses and eventually results in symptoms, usually facial weakness or numbness. The disease eventually extends to the skull base and becomes incompletely resectable. Symptomatic patients are defined as having "clinical" perineural invasion, and aggressive treatment results in a cure rate of approximately 45%. CONCLUSIONS: Perineural invasion is an uncommon spread pattern observed in patients with skin cancer and is associated with a relatively poor prognosis. The likelihood of cure is inversely related to the proximal extent of the cancer and is lower for symptomatic compared with asymptomatic patients.  相似文献   
68.
Lung cancer is not commonly known to metastasise to the perirenal space, with only five such cases previously published. We present an unusual case of perirenal lung metastases manifesting as diffuse perinephric stranding which to our knowledge has not been described before.  相似文献   
69.
The majority of breast cancer research is conducted using established breast cancer cell lines as in vitro models. An alternative is to use cultures established from primary breast tumours. Here, we discuss the pros and cons of using both of these models in translational breast cancer research.  相似文献   
70.
Paracetamol is the commonest agent employed in self poisoning, however it is not clear whether adolescents possess insight into the serious complications associated with its misuse. Using a one page questionnaire, the availability, usage, and knowledge of toxicity of paracetamol among 1147 American and British adolescents was assessed. Although 90% of all students recognised that paracetamol could kill, the great majority of students overestimated the lethal dose. In addition, while knowledge regarding side effects of paracetamol was poor the drug was widely available to, and used by, the study population. It is proposed that gross overestimation of the number of tablets required to kill, poor understanding of paracetamol side effects, and wide availability of the drug contribute to its frequent use in adolescent suicidal behaviour. The inclusion of some over-the-counter medications in school drug education programs in addition to tighter control of the availability of paracetamol may help reduce the problem of adolescent self poisoning.  相似文献   
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