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31.
Between 1970 and 1990, 104 patients with squamous cell carcinoma (SCC) of the tonsil were treated. The median age was 58 years and 80% of patients were males. Distribution among clinical stages was: stage I, 19 patients; stage II, 12 patients; stage III, 23 patients; and stage IV, 48 patients. More than 70% of patients had initial radiotherapy as definitive treatment irrespective of stage, reflecting the treatment philosophy over much of this period. The overall survival rate was 26% at 5 years, with survival being significantly affected by T stage, clinical stage and age. Clinical node status did not significantly affect survival rates. Good local control of T1N0 cancers was achieved with radiotherapy alone, but patients with more advanced cancers did poorly. We have now moved away from a non-selective policy and use initial surgery combined with postoperative radiotherapy in most patients, reserving radiotherapy alone for mainly early tonsil cancers.  相似文献   
32.
对1971—1990年间加拿大不列颠哥伦比亚癌症中心收治的428例鼻咽癌病人的发病和治疗情况进行分析。其中,中国人占303例(71%),白种人116例(27%)。中国人在该省鼻咽癌的年发病率是白种人的64倍,其中又以在中国出生的发病率最高,分别为白种人的104倍和北美出生的中国人的16倍。本组总的5年和10年生存率分别为51%和39%,颈淋巴结阴性的病人5年生存率达64%;而阳性的病人只有44%。鼻咽癌的预后与它的临床分期、病理类型、治疗前有无做颈淋巴结活检,以及性别有关,而与病人的人种和出生地无关。  相似文献   
33.
The results of external beam radiotherapy for clinically localized adenocarcinorna of the prostate in 448 patients treated in the period 1980–90 were reviewed. The average follow up was 4.9 years. The patients were aged 44–87 years (median 69 years) and all had histopathological evidence of adenocarcinoma by needle biopsy or transurethral resection of prostate. The histopathological grading was: 127 G1; 154 G2; 127 G3; 12 G4; 28 Gx. Clinical staging according to TNM (American Urological Association) was: 29 T0 (A2); 4 T1 (B1); 173 T2 (B2); 176 T3 (C1); 63 T4 (C2); 3 Tx. Routine surgical pelvic lymph node staging was not performed but patients had radiological (computerized tomography scan or lymphogram) nodal staging: 350 N0; 22 N1; 12 N2; 64 Nx. High energy linear accelerator external beam radiotherapy was given by multiple fields to total doses of 50–70 Gy (median 60 Gy). The majority of patients (307, 69%) was treated by a uniform policy under the care of one radiation oncologist (HM). The rates of local and distant failure at 5 years were 10% (s.e. = 2%) and 42% (s.e. = 3%), respectively. The late complication rate at 5 years was 25% (s.e. = 2%), comprising mild 16%, moderate 7% and severe 1.3%. The 5 year overall survival rate was 64% (s.e. = 2%) and the cancer-specific survival rate was 74% (s.e. = 3%). Both histological grade and clinical stage were strongly predictive of overall survival and distant failure. Only histological grade was predictive of local failure. Treatment with external beam radiotherapy for this common cancer resulted in survival and disease control rates that compare favourably with other published radiotherapy series and has been accompanied by acceptably low morbidity.  相似文献   
34.
放射治疗骨转移癌疼痛47例临床分析   总被引:10,自引:0,他引:10  
目的 观察骨转移癌疼痛放射治疗方法对疼痛的缓解效果。方法47例患者60处骨转移灶均采用6 MV X线放射治疗。剂量方案采用两种方法:A方案:30—51 Gy/10~17f/2~4周,B方案:25~30 Gy/5—6f/1~2周。结果分次方案对疼痛缓解率无明显影响,总有效率均为91.5%,但常规分次放疗3~4次后疼痛缓解,而低分割放疗1—2次后疼痛即缓解。结论 骨转移癌放射治疗止痛效果确切、迅速,副作用小,对大部分病例可采用低分割方案。  相似文献   
35.
三维超声技术及其在肝癌诊治中的应用   总被引:2,自引:0,他引:2  
介绍三维超声成像技术的原理,讨论三维超声在肝癌的诊断性应用及在肝脏手术和介入中的治疗性应用。  相似文献   
36.
BACKGROUND: The addition of short course pre-operative radiotherapy to total mesorectal excision reduces local recurrence in resectable adenocarcinoma of the rectum. In a previous retrospective study potential factors associated with early complications following this combination were identified. The aim of this study was to examine these relationships in a prospective multicentre audit. METHODS: One hundred and seven patients who received short course pre-operative radiotherapy in four cancer centres between 1 October 2001 and 30 September 2002 were included. Data including patient age, radiotherapy field length, overall treatment time, operation type, surgical outcomes and complications occurring within 3 months of the 1st day of radiotherapy were collected. These were compared and combined with the previously studied cohort of 176 patients treated at one centre between 1st January 1998 and 31st December 1999. RESULTS: In the prospective cohort only patient age (P=0.001) was significantly associated with acute complications. However, both the overall treatment time (median 9.0 vs 11.0 days P <0.0001) and field length (median 16.6 vs 17.0 cm P=0.03) were significantly shorter in this cohort when compared to the previous retrospective study. In patients from both studies (n=283), increasing age (P=0.002) and field length (independent of operation type) (P=0.02) were independently associated with an increased risk of acute complications. CONCLUSIONS: This study suggests that meticulous selection of patients for short course pre-operative radiotherapy and smaller planning target volumes may be associated with a lower risk of acute complications. The use of MRI scanning to stage pelvic disease may reduce the number of patients with R1 resections receiving short course pre-operative radiotherapy.  相似文献   
37.
The purpose of this study was to evaluate the dose to normal tissues as a function of increasing margins around the lumpectomy cavity in accelerated partial breast irradiation (APBI) using 3D-conformal radiotherapy (3DCRT). Eight patients with Stage 0-I breast cancer underwent treatment planning for 3DCRT APBI. The clinical target volume (CTV) was defined as a 15-mm expansion around the cavity limited by the chest wall and skin. Three planning target volumes (PTV1, PTV2, PTV3) were generated for each patient using a 0, 5-, and 10-mm expansion around the CTV, for a total margin of 15, 20, and 25 mm. Three treatment plans were generated for every patient using the 3 PTVs, and dose-volume analysis was performed for each plan. For each 5-mm increase in margin, the mean PTV:total breast volume ratio increased 10% and the relative increase in the mean ipsilateral breast dose was 15%. The mean volume of ipsilateral breast tissue receiving 75%, 50%, and 25% of the prescribed dose increased 6% to 7% for every 5 mm increase in PTV margin. Compared to lesions located in the upper outer quadrant, plans for medially located tumors revealed higher mean ipsilateral breast doses and 20% to 22% more ipsilateral breast tissue encompassed by the 25% IDL. The use of 3DCRT for APBI delivers higher doses to normal breast tissue as the PTV increases around the lumpectomy cavity. Efforts should be made to minimize the overall PTV when this technique is used. Ongoing studies will be necessary to determine the clinical relevance of these findings.  相似文献   
38.
螺旋CT扫描与多模式三维重建诊断腰椎间盘突出症   总被引:4,自引:0,他引:4  
目的 探讨螺旋CT扫描容积数据与三维重建诊断腰椎间盘突出症(LDH)的价值。资料与方法 94例行连续容积扫描:准直3~5mm,螺距1.5~3.0,以1.3~2.7mm间距后重建;源影像输入AW4.0工作站,应用多平面重建(MPR)、表面遮盖显示(SSD)和仿真内镜(VE)等软件显示病变,并与椎间盘镜(MED)诊治对照。结果 8例正常;LDH86例:中央型、侧旁、椎间管、椎管外、侧方及混合型分别为19、39、5、2、3、18例。三维重建显示LDH的立体结构为堤坡形、扁丘形、尖丘形、双(多)丘形及游离形分别为34、26、9、5、2例。VE诊断LDH的准确度、灵敏度、特异度分别为95%、100%、80%。VE能模拟MED效果。结论 容积数据与多模式三维重建能提供诊断LDH更全面的信息,并模拟微创手术治疗。  相似文献   
39.
OBJECTIVE: The indications for pre-operative radiotherapy in rectal cancer are still unclear with the exception of T4 tumours. The aim of this study was to assess local and overall recurrence in patients with T1-T3 rectal cancers undergoing total mesorectal excision (TME). METHODS: Prospective data was collected from 150 patients with rectal cancer treated in one surgical centre between July 1997 and July 2002. One hundred and twenty-nine primary resections were carried of which 102 were with curative intent. Seventy-nine patients with T1-T3 tumours were included in the analysis. Nine had local resections and 70 underwent TME; 19 of the 70 patients were node positive and 51 were node negative. RESULTS: At a median follow-up of 37 months (range 19-79 months) there were 3 (4.3%) isolated local recurrences. One node positive patient developed isolated local recurrence compared with 2 node negative patients. The node positive patient died from a myocardial infarction while the two node negative patients died as a consequence of local recurrence. Three (4.3%) of 70 patients developed systemic relapse all of whom were node positive. The cancer specific mortality rate over the same follow-up period was 3/19 for node positive patients and 2/51 for node negative patients. Of 9 patients who had local resections, none developed local recurrence or systemic relapse. CONCLUSIONS: With TME the rate of local recurrence in T1-T3 tumours is low. Our results do not support the use of pre-operative radiotherapy for these patients.  相似文献   
40.
This paper describes 29 patients with Ewing's sarcoma of bone treated between 1975 and 1990 at the University of Nijmegen Hospital, Nijmegen, The Netherlands. Osteomyelitis was the primary diagnosis in 24%. Treatment consisted of chemotherapy in combination with surgery and/or radiotherapy. Nine patients received radiotherapy only; five of them died of disease. Five patients underwent an intralesional excision; four of them died of disease. Twelve patients underwent a wide excision; there is no evidence of disease in any of them. Three patients underwent a radical disarticulation; all died of disease. The disease-free survival at 1.5 years was 66%. This figure at 5 years was 55%. After wide excision and reconstruction in tumors of expendable, femoral or radial bones good functional results were obtained in all cases. © 1995 Wiley-Liss, Inc.  相似文献   
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