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1.
高剂量率^192Ir后装近距离放疗中晚期直肠癌 总被引:1,自引:0,他引:1
目的:分析高剂量率^192Ir后装近距离放疗在中晚期直肠癌中的价值。方法:38例中晚期直肠癌,综合组高剂量^192Ir后装近距离放疗结合外照射放疗20例,对照组单纯外照射18例。高剂量率^192Ir后装近距离放疗根据肿瘤形态采用组织间插植术和腔内放疗,2周4次完成,总剂量24Gy-28Gy。1周后外加 照射。对照组外照射盆腔野总剂量45Gy-50Gy,2次/d。结果:临床证状改善,局部肿瘤消退情况 相似文献
2.
近距离照射犬胆管粘膜急性放射性损伤的研究 总被引:4,自引:0,他引:4
目的 寻找动物胆管金属内支架植入方法,观察支架内近距离照射的胆管急性放射性损伤。方法 实验动物为体重17~22kg的实验用雄性杂种犬。照射方法及条件:麻醉下经手术植入胆管金属内支架,将^192Ir施源器放入支架内并给予5~50Gy不同剂量的照射,1周后取胆管标本行放射损伤的评价。结果 ^192Ir不同剂量照射后光镜下可见的胆管损伤;照射5Gy,在胆管HE染色上,光镜下可观察到粘膜损伤,10Gy时放 相似文献
3.
作者对48例首次治疗的鼻咽癌患者采用外照射结合腔内高剂量率近距离治疗。其中计划性内外照射44例,外照射后补量4例。腔内治疗使用 ̄(192)Ir放射源,剂量参考点设在距放射源中心轴0.8~1.5cm处。每次参考点剂量6~8Gy,共1~3次。外照射剂量为60~80Gy。治疗结束时鼻咽癌局部控制率93.8%。1年和2年生存率分别为97.8%和95.5%。作者结合文献对腔内治疗的适应证及内外照射的剂量匹配进行探讨。 相似文献
4.
逐步递量加速超分割照射加化疗非小细胞肺癌 总被引:25,自引:1,他引:24
目的 观察逐步递量加速超分割放射治疗(EHART)Ⅲb期非小细胞肺癌(NSCLC)的近期疗效和急性放射反应。方法 73例Ⅲb期NSCLC进入EHART组。放射治疗的第1,2周,1.2Gy2次/d间隔6h以上,第3,4,5周分别为1.3,1.4,1.5Gy2次/d,均5天/周,照射野仅包括胸部CT或MRI可见的原发灶和淋巴结转移以及周围1.0~1.5cm的正常组织。肿瘤灶总剂量66Gy,50次,5周 相似文献
5.
目的 研究铱^192高剂量率后装加外照射治疗宫颈癌的疗效,并发症等。方法 前瞻性治疗,全盆腔外照射DT25-30Gy/3,再行腔内铱^192后装治疗和盆腔四野垂直照射;腔内每周1次,A点剂量每次5-7Gy,一30-35Gy,盆腔四野照射,宫旁剂量15-20Gy/1.5-2周。结果 CR+PR10%,3年生存率Ⅱ期89.5%,Ⅲ期80.4%,全组83.8%。 相似文献
6.
[目的]评估布克勒(Buchler)137Cs后装腔内放疗机治疗Ⅱ、Ⅲ期宫颈癌的远期疗效。[方法]总结1986年10月至 1987年 12月间应用“Buchler”后装机合并60CO或8MeV直线加速器对Ⅱ、 Ⅲ期的宫颈癌 140例进行根治性放射治疗。放疗剂量:腔内放疗Ⅱ期A点60Gy~72Gy,阴道与宫腔剂量比为4:3或1:1,随后外照射B点则采用盆腔四野照射,剂量44Gy~56Gy。Ⅲ期先采用盆腔全盆大野外照射B点20Gy~29Gy,随后盆腔四野外照射,B点补至456y~55Gy。盆腔四野照射期间配合腔内放疗A点50Gy~60Gy,阴道与宫腔剂量比为3:2或1:1。[结果]全组患者随访10年,其中7人失访,随访率为95%(133/140)。Ⅱ、 Ⅲ期宫颈癌的10年生存率分别为59%(36/61)、31.64%(25/79),总的10年生存率为43.57%(61/140)。[结论]布克勒后装腔内治疗机对宫颈癌的远期疗效比国内报道低,治疗合并症放射性直肠炎、膀胱炎、阴道炎均较高。 相似文献
7.
鼻咽癌组织照射前后细胞凋亡的临床意义初探 总被引:2,自引:0,他引:2
目的 采用末端脱氧核苷酸转移酶介导的脱氧核苷酸切口末端标记(TNUEL)法检测鼻咽癌患者不同剂量照射前后肿瘤细胞凋亡的变化,并初步探讨其潜在临床意义。方法 将接受根治性放射治疗的病理证实为鼻咽低分化鳞状细胞癌的25例患者分为5个组。5个组分别在分割剂量1.9Gy/次照射1~5次后3~6h活极取鼻咽癌肿瘤组织。采用TUNEL免疫组织化学法检测鼻咽癌组织放射治疗前、后肿瘤细胞凋亡。结果 放射治疗前、后 相似文献
8.
兔髂动脉腔内照射预防血管成形术后再狭窄实验研究初报 总被引:4,自引:0,他引:4
目的 评价兔髂动脉内近距离治疗预防经皮经腔血管成形术(PTA)后再狭窄的可行性及作用。方法 29只兔髂动脉进行PTA后制成动脉狭窄模型,4周后将狭窄病灶分为3个组:(1)8只作为对照组,仅作PTA;(2)9只PTA后^192Ir腔内照射10Gy;(3)12只PTA后^192Ir腔内照射18Gy。全部兔饲养4周后活杀,取病理组织学标本进行分析。结果 新内膜面积1 ̄3组分别为(13.85±6.92)μ 相似文献
9.
超分割放射治疗食管癌的长期疗效 总被引:20,自引:4,他引:16
目的 评价超分割放射治疗食管癌的长期疗效及放射反应和并发症。方法 92例食管癌随机分为2组:常规分割放射治疗组46例,1次/d,2.00Gy/次,5次/周,总剂量70.0Gy,35次,47~56d;超分割放射治疗组46例,2次/d,1.15Gy/次,间隔4~6h,5d/周,总剂量80.5Gy,70次,49~53d。全部商例均采用^60Co照射。结果 2个组急性和晚期放射反应差异无显著意义(P〉0. 相似文献
10.
鼻咽癌体外照射 腔内及咽旁间隙插植近距离放射治疗技术初探 总被引:6,自引:0,他引:6
放射治疗是治疗鼻咽癌的主要方法。鼻咽癌腔内近距离放射治疗(后装放射治疗)是体外照射的补充手段,但仍存在以下问题:(1)腔内放射治疗只适用于鼻咽腔内的浅表病变,对于咽旁间隙、蝶窦、筛窦受累者难以奏效;(2)从腔内施源器置入技术来看,其固定方法、与软腭的距离及与肿瘤的关系仍不够理想;(3)鼻咽癌高剂量率后装放射治疗的理想剂量分割方法有待进一步探索和完善。作者从1996年2月至1997年5月,采用核通公司的192Ir高剂量率后装治疗机(microSelectronHDR)对106例鼻咽癌病人进行了6… 相似文献
11.
BACKGROUND AND PURPOSE: This paper investigates the outcome using different dose/fractionation schedules in high dose rate (HDR) post-operative vaginal vault radiotherapy in patients with low to intermediate risk endometrial cancer. MATERIALS AND METHODS: The world literature was reviewed and thirteen series were analyzed representing 1800 cases. RESULTS: A total of 12 vaginal vault recurrences were identified representing an overall vaginal control rate of 99.3%. A wide range of dose fractionation schedules and techniques have been reported. In order to analyze a dose response relationship for tumor control and complications, the biologically effective doses to the tumor and late responding tissues were calculated using the linear quadratic model. A threshold was identified for complications, but not vaginal control. While dose fractionation schedules that delivered a biologically effective dose to the late responding tissues in excess of 100 Gy(3) (LQED=60 Gy) predicted for late complications, dose fractionation schedules that delivered a modest dose to the vaginal surface (50 Gy(10) or LQED=30 Gy) appeared tumoricidal with vaginal control rates of at least 98%. CONCLUSIONS: By using convenient, modest dose fractionation schedules, HDR vaginal vault - brachytherapy yields very high local control and extremely low morbidity rates. 相似文献
12.
Safwat A Nielsen OS El-Badawy S Overgaard J 《International journal of radiation oncology, biology, physics》1996,34(1):85-91
PURPOSE: Interstitial pneumonitis (IP) is still a major complication after total body irradiation (TBI) and bone marrow transplantation (BMT). It is difficult to determine the exact role of radiation in this multifactorial complication, especially because most of the experimental work on lung damage was done using localized lung irradiation and not TBI. We have thus tested the effect of radiation dose rate and combining cyclophosphamide (CTX) with single fraction TBI on lung damage in a mouse model for BMT. METHODS AND MATERIALS: TBI was given as a single fraction at a high dose rate (HDR, 0.71 Gy/min) or a low dose rate (LDR, 0.08 Gy/min). CTX (250 mg/kg) was given 24 h before TBI. Bone marrow transplantation (BMT) was performed 4-6 h after the last treatment. Lung damage was assessed using ventilation rate (VR) and lethality between 28 and 180 days (LD(50/28-180)). RESULTS: The LD50 for lung damage, +/- standard error (SE), increased from 12.0 (+/- 0.2) Gy using single fraction HDR to 15.8 (+/- 0.6) Gy using LDR. Adding CTX shifted the dose-response curves towards lower doses. The LD50 values for the combined treatment were 53 (+/- 0.2) and 3.5 (+/- 0.2) Gy for HDR and LDR, respectively. This indicates that the combined effect of CTX and LDR was more toxic than that of combined CTX and HDR. Lung damage evaluated by VR demonstrated two waves of VR increase. The first wave of VR increase occurred after 6 weeks using TBI only and after 3 weeks in the combined CTX-TBI treatment, irrespective of total dose or dose rate. The second wave of VR elevation resembled the IP that follows localized thoracic irradiation in its time of occurrence. CONCLUSIONS: Lung damage following TBI could be spared using LDR. However, CTX markedly enhances TBI-induced lung damage. The combination of CTX and LDR is more toxic to the lungs than combining CTX and HDR. 相似文献
13.
Sait Okkan Gülyüz Atkovar Ismet Sahinler Fazilet Oner Din?ba? Ay?e Koca Sel?uk K?ksal Sedat Turkan Reha Uzel 《Radiotherapy and oncology》2003,67(1):97-105
PURPOSE: To evaluate the results and complications of treatment with high dose rate (HDR) compared to low dose rate (LDR) brachytherapy in cervical carcinoma. METHODS: Three hundred and seventy patients who were treated with external irradiation and intracavitary brachytherapy and followed for more than 2 years between 1978 and 1998 have been recently updated. The low dose rate group consisted of 77 cases treated between 1978 and 1982 and HDR group consisted of 293 cases treated between 1982 and 1998. All patients first received external irradiation with 60Co or 9-18 MV photons and a median dose of 54 Gy was given in 6 weeks. In the LDR group, intracavitary treatment was given with Manchester applicators loaded with radium (30 mg) in an intrauterine tube and 20 mg in vaginal ovoids. The dose delivered to point A was on average 32 Gy in one application. In the HDR group, a total dose of 24 Gy was given to point A in three insertions 1 week apart. The dose rate was 0.62 Gy at point A. RESULTS: The 5-year pelvic control rate was found to be 73% in the HDR group, compared with 86% in the radium group for stage I cases. In stage IIB and IIIB cases, the rates were 68% and 45% for HDR and 65% and 53% for LDR, respectively. In all stages, there was no statistical difference in pelvic control and survival rates between the two groups. Overall incidence of late complications was found as 31.1% and 31.9% in HDR and LDR groups, respectively. The grade 2-4 late complication rate was 14% in the HDR group compared to 19% in the LDR group (P>0.05). CONCLUSION: HDR brachytherapy in the management of the cervix appears to be a safe and efficacious approach. Pelvic control, survival and complications rates are quite similar when compared with LDR. 相似文献
14.
V Vegesna H R Withers J M Taylor 《International journal of radiation oncology, biology, physics》1989,17(5):1027-1031
Single and fractionated dose response curves for hair follicles in two different growth activities were compared to analyze the difference in sparing associated with fractionation. Doses per fraction ranged from 8.0 Gy to 2.5 Gy from a 137Cs source. The maximum score for epilation, either at 4 weeks (growing follicles) or at 8.5 weeks (resting follicles) from treatment, was evaluated from a 6-point, graded scale of epilation. The dose to produce a given hair response in 50% of animals (HRD50) was calculated using logit analysis. For both growing and resting follicles, the HRD50 values increased with decrease in fraction size. However, when the dose per fraction was decreased below 4.0 Gy, the increase of isoeffect dose was less for growing follicles but continued at the same rate for resting follicles. This difference in the slope of isoeffect curves was analyzed in terms of alpha/beta ratio in the linear quadratic model. The estimates with 95% confidence intervals were 6.0 Gy (5.2-6.8 Gy) and 3.6 Gy (3.1-4.2 Gy) for growing and resting follicles, respectively, for doses per fraction less than 7 Gy. For resting follicles, the plot of isoeffect inverse total dose versus dose per fraction was nonlinear. There was no correlation between the response within the same animal of early occurring epilation in growing follicles to the late occurring epilation in resting follicles though the site and origin of the tissue was the same and it differed only in turnover kinetics. This suggests that the response of organs is related to random cell killing rather than to animal specific variations in radiosensitivity, at least in an inbred strain of mice. 相似文献
15.
C W Langberg T Sauer J B Reitan M Hauer-Jensen 《Acta oncologica (Stockholm, Sweden)》1992,31(7):781-787
The tolerance of rat small intestine to localized single-dose and fractionated irradiation was assessed. In 168 rats, bilateral orchiectomy was performed and a loop of small intestine was transposed to the left part of the scrotum. Beginning 3 weeks postoperatively, single dose (18-24 Gy) or fractionated (4.2 Gy or 5.6 Gy per fraction) x-irradiation was delivered to the transposed intestine. The animals were observed for complications, and groups of animals were killed 2 and 26 weeks after completion of irradiation for assessment of injury. Mortality (i.e. the occurrence of lethal intestinal complications) and a semiquantitative histopathologic scoring system were used as endpoints to assess the degree of radiation injury. The most frequent intestinal complications were enterocutaneous fistula formation and intestinal obstruction. Logistic regression analysis ov complications data was used to estimate LD50 values and the alpha/beta ratio. There was good correlation between histopathologic scores and the incidence of lethal complications. The estimated LD50 values were 22.1 +/- 0.5 Gy, 37.0 +/- 4.4 Gy and 51.0 +/- 5.3 Gy for the single dose regimen and the fractionated regimens of 5.6 Gy and 4.2 Gy respectively. The estimated alpha/beta ratio was 10.7 +/- 2.4 Gy. The goodness of fit of the linear-quadratic isoeffect model to our data was satisfactory. Our results indicate that acute mucosal damage may be pathogenetically involved in the development of intestinal complications. 相似文献
16.
The influence of radiation dose rate and drug dose on the combined effects of cisplatin (Cis-diamminedichloroplatinum (II] and radiation on the skin and soft tissues was studied in the C3Hf/SED mice. Localized acute-dose-rate irradiation (ADRI) at 3.345 Gy/min and continuous low-dose-rate irradiation (CLDRI) of the hind leg at 0.028 Gy/min with and without the drug was delivered using a 137Cs laboratory irradiator. Cisplatin at 6 or 11 mg/kg was given by intraperitoneal bolus injection 1 hour before ADRI or by continuous infusion during CLDRI. Acute skin reaction was scored from days 13 to 30 and late skin contraction and leg contracture were measured at days 90, 180, 270, and 360 after treatment. A marked dose-rate effect was observed for these early and late normal tissue endpoints. At a dose of 60 Gy of CLDRI, the dose rate factor (DRF = isoeffect dose at CLDRI/isoeffect dose at ADRI) was 1.82 for acute skin reaction and 1.76 for late skin contraction or leg contracture at day 270. However, there was no significant enhancement of these early and late normal tissue effects by cisplatin at 6 or 11 mg/kg at either acute or low dose rates. Thus neither drug dose nor radiation dose rate had a significant impact on the combined effects of cisplatin and radiation on the mouse skin and soft tissues of the leg. 相似文献
17.
Akagi Y Hirokawa Y Kagemoto M Matsuura K Ito A Fujita K Kenjo M Kiriu H Ito K 《International journal of radiation oncology, biology, physics》1999,43(3):525-530
PURPOSE: To establish the optimum fractionation for high-dose-rate (HDR) endoesophageal brachytherapy (EBT) for early stage esophageal cancer from retrospective data of patients treated with different HDR schedules following external beam irradiation (EBI). METHODS AND MATERIALS: The study population consisted of 35 consecutive early stage esophageal cancer patients who received EBI to the mediastinum, plus EBT, between May 1992 and November 1995 at the Hiroshima University Medical Center and Hiroshima City Hospital. All patients were treated with EBI, with doses ranging from 50 to 61 Gy. The spinal cord was spared after 44-45 Gy. HDR EBT was performed using a double-balloon applicator in conjunction with an Ir-192 remote afterloading system. One group of 10 patients was given a weekly endoesophageal boost of 4 or 5 Gy at a distance of 5 mm from the applicator surface over a period of 1-2 weeks. Another group of 25 patients was treated with 4 or 5 endoesophageal boosts with a fraction dose of either 2.5 or 2 Gy for 1 week. The linear quadratic (LQ) formula was used to calculate the biologically effective dose (BED) for tumor (Gy10) and esophageal mucosa (Gy3); Gy10 means alpha/beta equals 10 Gy, and Gy3 means alpha/beta equals 3 Gy.The Kaplan-Meier method was used to calculate the local control and late complication rates, while the Cox-Mantel test was used to evaluate statistical significance (p < 0.01). RESULTS: Nine (26%) of the 35 patients recurred locally and 7 (20%) had late complications (esophageal ulcer grade by RTOG/EORTC criteria > 1). The 5-year overall survival, local control, and late complication rates were 38%, 57%, and 26%, respectively. The probability of local recurrence was not affected by the treatment parameters. Results from the LQ formula significantly correlate with data on late complications. A BED > 134 Gy3 and a fraction number = < 3 were associated with late complications (grade > 1). BED analysis showed that the fractionation dose should be decreased to 2.5 or 2.0 Gy at a distance of 5 mm from the applicator surface, and the number of doses increased to 4 or 5, respectively, to yield a satisfactory BED (< 134 Gy3). CONCLUSION: A significant reduction in endoesophageal brachytherapy dose per fraction is necessary to reduce late complications. Our current treatment protocol for early-stage esophageal cancer consists of EBI of 60 Gy followed by 4 EBT doses at a fraction dose of 2.5 Gy applied over 1 week. 相似文献
18.
BACKGROUND: Traditionally, low dose rate (LDR) brachytherapy has been used as a standard modality in the treatment of patients with carcinoma of the uterine cervix. The purpose of this work was to evaluate the effects of high dose rate (HDR) brachytherapy on patients with adenocarcinoma of the uterine cervix and to compare them with the effects of LDR brachytherapy. METHODS: From January 1971 to December 1992, 104 patients suffering from adenocarcinoma of the uterine cervix were treated with radiation therapy in the Department of Radiation Oncology, Yonsei University. LDR brachytherapy was carried out on 34 patients and HDR brachytherapy on 70 patients. In the LDR group, eight patients were in stage IB, six in IIA, 12 in IIB, three in IIIA and five in IIIB. External radiation therapy was delivered with 10 MV X-rays, 2 Gy fraction per day, total dose of whole pelvis 36-52 Gy (median 46 Gy). LDR radium intracavitary irradiation was performed with a Henschke applicator, 37-59 Gy targeted at point A (median 43 Gy). In the HDR group, there were 16 patients in stage IB, six in IIA, 32 in IIB and 16 in IIIB. The total whole pelvis dose of external radiation was 40-50 Gy (median 44 Gy), daily 1.8-2.0 Gy. HDR Co-60 intracavitary irradiation was performed with a remotely controlled after-loading system (RALS), 30-48 Gy (median 39 Gy) targeted at point A, three times per week, 3 Gy per fraction. RESULTS: The 5-year overall survival rate in the LDR group was 72.9, 61.9 and 35.7% in stage I, II and III, respectively and the corresponding figures for HDR were 87.1, 58.3 and 43.8% (p > 0.05). There was no statistical difference between the HDR group and the LDR group in terms of the 5-year overall survival rate from adenocarcinoma of the uterine cervix. There was a late complication rate of 12% in the LDR group and 27% in the HDR group. The incidence of late complications in stages II and III was higher in the HDR group than in the LDR group (31.6 vs 16.7% in stage II, 37.3% vs 12.5% in stage III, p > 0.05). No prognostic factors were evident in the comparison between the two groups. CONCLUSION: There was no difference in terms of 5-year survival rate in the patients with adenocarcinoma of the uterine cervix between those treated with HDR and those treated with LDR brachytherapy. Even though late complication rates were higher in the HDR group, most of them were classified as grade I. This retrospective study suggests that HDR brachytherapy may be able to replace LDR brachytherapy in the treatment of adenocarcinoma of the uterine cervix. 相似文献
19.
R P Hill 《International journal of radiation oncology, biology, physics》1983,9(7):1043-1047
Groups of LAF1 mice were given thoracic irradiation using 60Co gamma-rays at dose-rates of 0.05 Gy/min (LDR) or 1.1 Gy/min (HDR) and the death of the animals was monitored as a function of time. It was found that the time pattern of animal deaths was similar for the two different dose-rates. Dose response curves for animals dying at various times up to 500 days after irradiation were calculated and the LD50 values determined. The curves for the LD50 values, plotted as a function of the time at analysis for treatment at HDR or LDR, were essentially parallel to each other but separated by a factor (LDR/HDR) of about 1.8. This indicates that the sparing effect of LDR treatment is the same for deaths occurring during the early pneumonitis phase or during the late fibrotic phase of lung damage. The available information on the response of patients to whole thoracic irradiation, given for either palliation or prior to bone marrow transplantation, suggests that for similar dose-rates to those studied here the ratio (LDR/HDR) is only 1.2-1.3. This difference between the animal and human data may reflect the modifying effect of the large doses of cytotoxic drugs used in combination with the irradiation of bone marrow transplant patients. 相似文献
20.
Petereit DG Pearcey R 《International journal of radiation oncology, biology, physics》1999,43(2):359-366
PURPOSE: A literature review and analysis was performed to determine whether or not efficacious high dose rate (HDR) brachytherapy fractionation schedules exist for the treatment of cervical cancer. METHODS AND MATERIALS: English language publications from peer reviewed journals were assessed to calculate the total contribution of dose to Point A from both the external and intracavitary portions of radiation for each stage of cervical cancer. Using the linear quadratic formula, the biologically effective dose to the tumor, using an alpha/beta = 10, was calculated to Point A (Gy10) in order to determine a dose response relationship for local control and survival. Significant complications were assessed by calculating the dose to the late-responding tissues at Point A using an alpha/beta = 3 (Gy3) as a surrogate for normal tissue tolerance, since few publications list the actual bladder and rectal doses. RESULTS: For all stages combined, the median external beam fractionation schedule to Point A was 40 Gy in 20 fractions, while the median HDR fractionation schedule was 28 Gy in 4 fractions. For stages IB, IIB, and IIIB the median biologically effective dose to Point A (Gy10) was 96, 96 and 100 Gy10s, respectively. No correlation was identified between Point A BED (Gy10s) to either survival or pelvic control. A dose response relationship could also not be identified when correlating Point A Gy3s to complications. CONCLUSION: A dose response relationship could not be identified for either tumor control nor late tissue complications. These findings do not necessarily question the validity of the linear quadratic model, as much as they question the quality of the current HDR brachytherapy literature as it is currently presented and reported. Most of the HDR publications report inadequate details of the dose fractionation schedules. Only a minority of publications report significant complications using the actuarial method. In the future, all HDR publications for the treatment of cervical cancer should provide accurate fractionation details for each stage of disease, while reporting actuarial complication rates. The optimal fractionation schedule for treating cervical cancer using HDR brachytherapy is still unknown, and presently can be based only on single institutions with significant experience. 相似文献