The influence of interstitial brachytherapy with ～(125)I seeds on Caspase-3 and Egr-1 expressions of Lewis lung carcinoma in C57BL mice

Objective:The aim of our study was to explore the influence of interstitial brachytherapy with 125I seeds on Caspase-3 and Egr-1 expressions of Lewis lung carcinoma in C57BL mice.Methods:Model mice of C57BL were planted with Lewis lung cells (LLC) and divided into the treatment group (n=18) and the control group (n=17).In each mouse of the treatment group,two BT-125-1 Model 125I seeds with apparent activity of 9.25 MBq were implanted into the tumor;whereas in each mouse of the control group two dummy seeds were implanted.The mice survival rates of both groups were recorded after 21 days.The tumor weights and dimensions of survived mice were measured,and the tumor volume inhibition rate was calculated.T-test was performed to compare differences of tumor weights and volumes between these two groups.Routine pathological slides of tumor tissue were observed under light microscope.The expression of Caspase-3 was detected by immunohistochemical method and the expression of Egr-1 was detected by RT-PCR method.Results:The survival rates were 88.88% in the treatment group and 70.59% in the control group,the difference had no statistical significance (P > 0.05).The tumor volume inhibition rate was 71.12%.Pathological examination showed degeneration and necrosis of cancer cells at the site nearby the seed in the treated group,but the tumor cells alive were still presented nearby the seed in the control group.The expressions of Caspase-3 and Egr-1 in the treated group were higher than those in the control group (t=12.825,P < 0.01;t=7.039,P < 0.01;respectively).Conclusion:The interstitial brachytherapy with 125I seeds could significantly inhibit the growth of Lewis lung carcinoma of mice.The possible mechanism may be that 125I interstitial brachytherapy can enhance the expressions of Egr-1 and Caspase-3,which could induce tumor cellular apoptosis.

Percutaneous biliary stent combined with brachytherapy using 125I seeds for treatment of unresectable malignant obstructive jaundice:A meta-analysis

BACKGROUND Malignant obstructive jaundice(MOJ)is a common pathologic manifestation of malignant biliary obstruction.Recently,several clinical trials have explored the clinical effectiveness of intraluminal^(125)I seed-based brachytherapy for MOJ patients,and various outcomes have been reported.AIM To assess the efficacy and safety of percutaneous biliary stents with^(125)I seeds compared to conventional metal stents in patients with unresectable MOJ.METHODS A systematic search of English-language databases(PubMed,Embase,Cochrane Library,and Web of Science)was performed to identify studies published prior to June 2020 that compared stents with or without^(125)I seeds in the treatment of unresectable MOJ.The outcomes analyzed included primary outcomes(stent patency and overall survival)and secondary outcomes(complications and liver function parameters).RESULTS Six randomized controlled trials and four retrospective studies involving 875 patients were eligible for the analysis.Of the 875 included patients,404 were treated with^(125)I seed stents,while 471 were treated with conventional stents.Unadjusted pooled analysis demonstrated that compared to conventional stents,^(125)I seed stents extended the stent patency time[hazard ratio(HR)=0.36,95%confidence interval(CI)=0.28-0.45,P<0.0001]and overall survival period(HR=0.52,95%CI=0.42–0.64,P<0.00001).Subgroup analyses based on the type of^(125)I seed stent and type of study design showed consistent results.However,there were no significant differences in the occurrence of total complications[odds ratio(OR)=1.12,95%CI=0.75-1.67,P=0.57],hemobilia(OR=1.02,95%CI=0.45-2.3,P=0.96),pancreatitis(OR=1.79,95%CI=0.42-7.53,P=0.43),cholangitis(OR=1.13,95%CI=0.60-2.13,P=0.71),or pain(OR=0.67,95%CI=0.22-2,P=0.47).In addition,there were no reductions in the levels of serum indices,including total bilirubin[mean difference(MD)=10.96,95%CI=-3.56-25.49,P=0.14],direct bilirubin(MD=7.37,95%CI=-9.76-24.5,P=0.4),alanine aminotransferase(MD=7.52,95%CI=-0.71-15.74,P=0.07),and aspartate aminotransferase(MD=-4.77,95%CI=-19.98-10.44,P=0.54),after treatment.Publication bias was detected regarding the outcome overall survival;however,the conclusions were not changed after the adjustment.CONCLUSION Placement of stents combined with brachytherapy using^(125)I seeds contributes to a longer stent patency and higher overall survival than placement of conventional stents without extra complications or severe liver damage.Thus,it can be considered an effective and safe treatment for unresectable MOJ.

Iodine-125 interstitial brachytherapy for experimental liver cancer

Objective：To study the effect of iodine-125 interstitial brachytherapy on liver cancer. Methods： Animal model of human liver cancer was established by injecting SMMC-7721 cells cultivated in vitro subcutaneously into the flank of BALB/c nude mice. Nude mice with tumor of 5 mm in diameter were randomly divided into 2 groups （n = 10）. One iodine-125 seed of apparent activity 0.8 mCi was implanted into the center of tumor in treatment group, whereas an inactive seed was implanted in control group. The other 20 nude mice with tumor reaching 10 mm in diameter were also treated as above. The size of tumor was determined weekly after implantation, and pathological examination and blood routine were taken on the 28th day. Results： Tumor growth was obviously inhibited in treatment group of tumor of 5 mm in diameter, and there was statistically significant difference in tumor volume between treatment and control groups （P〈0.01）. Around iodine-125 seed, apparent necrosis of tumor was shown in treatment group, accompanied by karyopyknosis and reduced plasma in residual tumor cells microscopically. Tumor growth was not inhibited in either treatment or control group of tumor of 10 mm in diameter. There was no obvious adverse effect except for decreased white blood cells in treatment groups. Conclusion： There is certain effect of iodine-125 interstitial braehytherapy on liver cancer, which is associated with the size of tumor.

Treatment of Unresectable Advanced Gastric Cancer Using lodine-125 Brachytherapy

OBJECTIVE The purpose of the study was to examine the efficacy of treating patients with advanced gastric cancer using iodine-125 （^125Ⅰ） brachytherapy. METHODS Ten patients with unresectable advanced gastric cancer were selected based on their pattern of CT scans. We utilized a brachytherapy planning system to determine the distribution of the ^125Ⅰ seeds, their activity and quantity. The matched peripheral dose （MPD） was 110-135 Gy.^125Ⅰ seeds were implanted in a single plane or biplane by an intraoperative small incision or percutaneous puncture. The postoperative hemogram, CT, KPS, pain-relieving period and survival period were recorded. RESULTS One patient developed a complete response （CR）, 4 patients a partial response （PR）, 3 patients showed no change （NC） and 2 patients developed progressive disease （PD）. The overall response rate （CR＋PR） was 50% （5/10）. The pain-relieving rate was 89% （8/9）. The patients＇ appetite and KPS were improved. The longest survival period was 10 months and median life span was 4 months. There were 8 patients whose seeds fell off resulting in an expulsion rate of 3.8% （26/692）. The patients showed 0-1 degree acute radio-therapeutic side-effects without other symptoms such as abdominal pain, vomitus cruentes or intestinal obstruction etc.CONCLUSION Applying ^125Ⅰ implantation to treat advanced gastric cancer with a reasonable seed distribution can significantly improve clinical symptoms and their quality of life. The radioactive damage is mild. This method can be used as an important supplementary treatment for unresectable advanced gastric cancer.

Automation System for Quality Control in Manufacture of Iodine-125 Sealed Sources Used in Brachytherapy

The objective of this work is to develop an automation system for quality control （QC） in the production of Iodine-125 sealed sources, after undergoing the process of laser beam welding （LBW）. These sources, also known as Iodine-125 seeds are used, successfully, in the treatment of cancer by brachytherapy, with low-dose rates. Each small seed is composed of a welded titanium capsule with 0.8 mm diameter and 4.5 mm in length, containing Iodine-125 adsorbed on an internal silver wire. The seeds are implanted in the human prostate to irradiate the tumor and treat the cancerous cells. The technology to automate the quality control system in the manufacture of lodine-125 seeds consists in developing and associate mechanical parts, electronic components and pneumatic circuits to control machines and processes. The automation technology for Iodine-125 seed production developed in this work employs programmable logic controller （PLC）, step motors, drivers of control, electrical-electronic interfaces, photoelectric sensors, interfaces of communication and software development. Industrial automation plays an important role in the production of Iodine-125 seeds, with higher productivity and high standard of quality, facilitating the implementation and operation of processes with good manufacturing practices （GMP）. Nowadays, the Radiation Technology Centre at IPEN-CNEN/SP imports and distributes 36,000 lodine-125 seeds per year for clinics and hospitals in the whole country. However, the Brazilian potential market is of 8,000 lodine-125 seeds per month. Therefore, the local production of these radioactive seeds has become a priority for the Institute, aiming to reduce the price and increase the supply to the population in Brazil.

Comparison between the Use of Loose and Stranded Seeds in Prostate Brachytherapy in Brazil

Cancer is a leading cause of death worldwide. In 2030, 26.4 million new cases will be diagnosed, with 17 million deaths accounted worldwide. Prostate cancer is the sixth most common type in the world, and the second most commom in men. For Brazil, the number of new cases of prostate cancer in 2010 is estimated to 52,350. Treatment of prostate cancer may be by surgery, radiation or even vigilant observation. A method of radiotherapy which has been extensively used is brachytherapy, where Iodine-125 seeds are placed inside or next to the area requiring treatment. Iodine seeds can be introduced loose seeds or stranded in bioabsorbable polymers in order to increase the dosimetric coverage of the prostate and reducing the chance of seed migration. Data were gathered concerning the commercialization of loose seeds and stranded seeds, between 2005 and 2011, in Brazil. It was noted that the number of stranded seeds commercialized in Brazil (around 80%) has always been much greater than the number of loose seeds, reaching 90% last year. The main reason is the reduction of the seed migration events into other parts of the body, since there is a potential hazard even considering that no harmful effect has been observe. The data regarding dosimetry are still controversial, since the seeds that migrate is normally no more than 1%.

Three-Dimensional Conformal Dose Planning for Prostate Brachytherapy

For local radiotherapy, a three-dimensional(3D)conformal localized dose planning protocol has been established in this paper to develop a precise and reasonable dose plan. A precalculated 3D dose map for a single source is obtained using the Monte Carlo method, and the spatial dose maps are combined linearly to acquire the dose distribution. The dose distribution is visualized through the real-time display of the isodose line and isodose surface combined with the reconstructed 3D organ groups. By observing 3D dose coverage to the target volume and surrounding tissues, dose planning could be initiated with greater accuracy and precision to avoid dose dead zones and excessively high-dose levels, thus achieving the 3D conformal dose planning objective. Further research into the impact that blockages have on a needle trajectory can be conducted to optimize the insertion accuracy. A treatment planning system was developed to formulate and implement the 3D local treatment plan before the surgery,during the surgery, and after the surgery. Several experiments pertaining to both single-seed and multiple-seed dose distributions were conducted to verify the accuracy of the single-seed dose calculation module and 3D superposition dose calculation in the treatment planning system.

Iodine-125 seed implantation in the treatment of malignant tumors

Malignant tumors are major causes of morbidity and mortality in China.Despite advances in surgical,radiological,chemotherapeutic,molecular targeting,and immunotherapeutic treatments,patients with malignant tumors still have poor prognoses.Low-dose-rate brachytherapy,specifically 125I seed implantation,is beneficial because of its high local delivery dose and minimal damage to surrounding tissues.Consequently,it has gained increasing acceptance as a treatment modality for various malignant tumors.In this study,we explored the fundamental principles,clinical applications,and new technologies associated with 125I radioactive seed implantation.

^(125)I粒子植入在难治性甲状腺癌治疗中的应用价值

作为近距离放射治疗的一种,^(125)I粒子植入已广泛应用于各种不可切除或局部复发的恶性肿瘤治疗中,均展现出良好的治疗效果与前景。由于具有疗效确切、安全微创的特点,^(125)I粒子植入为不能再次手术、^(131)I治疗不可控及不适合靶向治疗的持续或复发甲状腺癌提供了一种可选择的手段。该文将简要介绍^(125)I粒子植入在难治性甲状腺癌局部复发灶及其转移灶治疗和病灶术前定位中的应用。

Personalized radioprotection in tumor patients after^(125)I seed brachytherapy

Objective:To investigate patient-specific radioprotection mathods for people in close contact with cancer patientstreated by 12I-seed implantation.Methods:The initial dose rates(D_(0))at distances of 30 and 100 cm from 80 patients who had undergone ^(125)I-seed implantation were measured within 24 h of the procedure.The dose rate at t(D_(t))and effective dose(E)were calculated according to the measurad vales of D.The appropriate precaution times for general adult family members,spouses,coworkers,and children or pregnant women were determined,and the relationships between and precaution time for different close-contact groups were derived by curve-fitting the corresponding data.Results:The mean D vahes of 80 patients at distanes of 30 and 100cm were(15.24±11.25)μSv/h and(1.96±2.63)μSv/h,respectively(P<0.05).The mean values and range of precaution time for general adult familymembers,spouses,coworkers,and children or pregnant women were(4.17±16.55),(102.93±49.22),(51.00±61.29),and(34.27±56.90)d(0-90.61),(0-234.01),(0-247.81),and(0-224.69)d,respectively.Furthemore,a logarithmic relationship betwen D and precaution time(Y)was observed for the different groujps.The equations of these relationships were detemined to be Y=-131.569+83.256 lnD_(0) for general adult family mambers,Y=—108.532+83.318 lnD_(0) for spouses,Y=25.470+83.318 lnD,for coworkers,and Y=2.585+83.229 lnD_(0) for children or pregnant women.Conchusions:Some cancer patients treated by ^(125)I-seed brachytherapy emitover-dose levels of γ-rays,necessitatingradiation protection for their close contacts.However,appropriate patient-specific radiation protection fordifferent close contacts can be determined based on the precaution time calculated using the D_(0) value.

A prospective study:intraoperative ^(125)I radioactive seed implant therapy in advanced esophageal squamous cell carcinoma

Objective： To investigated the role of intraoperative iodine-125 （125I） brachytherapy as a treatment option for advanced thoracic esophageal squamous cell carcinoma （ESCC）. Methods： Using preoperative computed tomography （CT）-based staging criteria, between 2000 and 2008, 298 patients with ESCC （stage Ⅱ-Ⅲ） were enrolled in this prospective study. With informed consent, patients were randomized into two groups： intraoperative ^125^I seed implantation and surgery alone （control group）. Twenty to forty 125I seeds （0.5 mCi per seed）, with a total activity in 10-30 mCi, and a matched peripheral dose （MPD） of 60-70 Gy, were implanted under direct visualization. The surgical procedure used in this study was either a radical resection, which involved an esophagectomy through a left thoracotomy with two-field lymphadenectomy, or palliative resection. The postoperative complications were observed and recorded. The location and quality assessment of J25I seeds were assessed using CT scans or X-ray imaging. The short-term efficacy was evaluated according to WHO criteria. The 1, 3, 5 and 7-year survival rates were determined on follow-up. Results： There was no displacement or loss of 125I seeds. The local recurrence rates in the intraoperative 125I seed implantation group and control group were 14.9% and 38.7%, respectively （P 〈 0.05）. An objective response rate of 92% was observed in the seed implant group, which was significantly higher than 0% in the control group （P 〈 0.05）. There was no significant difference between the two groups when comparing of complications （P 〉 0.05）. The 1-year survival rate of the two groups were not significantly different （P 〉 0.05）. However, the 3, 5 and 7-year survival rates in the united 125I group （64%, 55.3% and 8%, respectively） were statistically different from those in the control group （52%, 29.1% and 1.4%,respectively）（P 〈 0.05）. Conclusion： Intraoperative 125I seed implantation is safe and effective for advanced ESCC. Seed implantation may reduce the local recurrence rate and improve survival in patients with ESCC. The MPD of 60-70 Gy, with single 125I seed activity of 0.5 mCi, is reasonable.

碘-125粒子治疗复发宫颈鳞癌术后剂量参数与疗效关系分析

目的探讨复发宫颈鳞癌粒子植入术后剂量参数与肿瘤体积缩小比的关系,并得出能够预测疗效的最佳参数。方法选取粒子植入治疗的宫颈鳞癌患者26例,共30个病灶。所有患者术后即刻行剂量验证,得出术后D_(90)。术后规律随访,根据患者实际随访时的CT图像计算术后t时刻肿瘤体积缩小比(R_(t))、术后1个月肿瘤体积缩小比(R_(1))、初月实际吸收剂量(D_(1m))、初月疗效校正吸收剂量(D_(1e))、初月敏感性校正吸收剂量(D_(1s))。将术后D_(90)与R_(1)进行曲线拟合,将术后D_(90)、D_(1m)、D_(1e)、D_(1s)与Rt进行曲线拟合,寻找各参数与肿瘤体积缩小比的关联性。结果术后D_(90)、D_(1m)、D_(1e)、D_(1s)、Rt、R_(1)均数分别为(105.4±22.8)Gy、(30.9±7.4)Gy、(37.1±8.9)Gy、(37.8±11.6)Gy、(39.4±17.0)%、(20.4±12.0)%。术后D_(90)与R_(1),术后D_(90)、D_(1m)、D_(1e)、D_(1s)与Rt均呈函数关系,方程式分别为y=6.856×10^(-7)x^(3)-2.66×10^(-4)x^(2)+0.031x-0.879(R^(2)=0.139),y=1.573×10^(-6)x^(3)-4.47×10^(-4)x^(2)+0.045x-0.967(R^(2)=0.027)、y=7.11×10^(-5)x^(3)-0.07x^(2)+0.193x-1.402(R^(2)=0.043)、y=3.546×10^(-5)x^(3)-0.003x^(2)+0.108x-0.744(R^(2)=0.126)、y=1.022×10^(-5)x^(3)-0.001x^(2)+0.048x-0.275(R^(2)=0.243)。结论术后D_(90)、D_(1m)、D_(1e)、D_(1s)与术后肿瘤体积缩小比有一定的相关性,可用于预测复发宫颈鳞癌粒子植入患者的疗效。相比D_(90)和D_(1m),D_(1e)与D_(1s)预测疗效可能更准确。

^(125)Ⅰ粒子治疗肺鳞癌术后剂量参数与疗效关系初探

目的探讨肺鳞癌^(125)Ⅰ粒子植入术后各剂量参数与肿瘤体积缩小比的关系,并得出预测疗效的最佳参数。方法回顾性分析2015年1月至2021年3月本院^(125)Ⅰ粒子植入治疗的26例肺鳞癌患者,共28个病灶。所有患者术后即刻行剂量验证,得出术后D_(90)(90%靶体积所接受的最小周边剂量)。术后规律随访,根据患者实际随访时的CT图像计算术后t个月肿瘤体积缩小比(R_(t))、术后1个月肿瘤体积缩小比(R_(1))、初月理论吸收剂量(D_(1m))、初月疗效校正吸收剂量(D_(1e))和初月敏感性校正吸收剂量(D_(1s))。将术后D90与R1进行曲线拟合,将术后D_(90)、D_(1m)、D_(1e)、D_(1s)与R_(t)进行曲线拟合,寻找各参数与肿瘤体积缩小比的关联性。结果术后D_(90)、D_(1m)、D_(1e)、D_(1s)、R_(t)和R_(1)分别为(113.56±27.61)Gy、(35.2±9.8)Gy、(45.8±17.9)Gy、(38.6±20.7)Gy、(34±39)%和(27±27)%。术后D_(90)与R_(1),术后D_(90)、D_(1m)、D_(1e)、D_(1s)与R_(t)均为正相关,关系方程分别为y=0.00001x^(2)+0.0019x-0.1331(R^(2)=0.234)、y=-0.0001x^(2)+0.0292x-1.4459(R^(2)=0.210)、y=0.5222lnx-1.4938(R^(2)=0.161)、y=-0.0004x^(2)+0.0489x-0.9973(R^(2)=0.503)和y=0.3909lnx-1.0304(R^(2)=0.287)。结论术后D_(90)、D_(1m)、D_(1e)、D_(1s)与术后肿瘤体积缩小比呈正相关,可用于预测肺鳞癌^(125)Ⅰ粒子植入患者的疗效,相较于术后D_(90)和D_(1m),D_(1e)与D_(1s)预测疗效可能更优。

To explore the curative effect of CT-guided Iodine-125 radioactive seed implantation in the treatment of stage Ⅳprimary hepatocellular carcinoma

Objectives: To explore the clinical efficacy and survival of CT-guided Iodine-125 radioactive seed implantation in the treatment of stage Ⅳ primary hepatocellular carcinoma.Methods: A retrospective study of 62 patients with primary hepatocellular carcinoma in our hospital from January2017 to December 2018 [60 males, 2 females, age(52.76 ± 10.82) years old], All patients were implanted with Iodine-125 radioactive seeds under CT guidance, followed up regularly after operation to observe the clinical efficacy, including comparison of changes in cancer size before and after treatment, tumor marker AFP, and improvement in complications such as abdominal pain and ascites. Follow-up 3–36 months to assess patient survival.Results: Among the 62 patients, 3 months after Iodine-125 radioactive seed implantation, 5 cases(8.1%) had complete remission of cancer, 33 cases(53.2%) had partial remission, 12 cases(19.4%) had stable lesions, and 12 cases(19.4%) had disease progression. The effective rate was 61.3%. The tumor volume(31.44 ± 14.51 cm3) was significantly smaller than before(50.96 ± 30.13 cm3)(t=5.303, p < 0.05). The tumor marker AFP(69.28 ±50.99) ug/L of 3 months after implantation was significantly lower than that before treatment(90.63 ± 68.58)ug/L(t=3.702, P < 0.05). The average survival time of Iodine-125 seed implantation for stageⅣhepatocellular carcinoma is 11.47 ± 0.85 months, and the median survival time is 9 months. The survival time of the group with better pathological differentiation(grade Ⅰ+ⅡⅠ) was significantly better than that of the group with poor differentiation(grade Ⅲ+Ⅳ)(x2=6.869 p < 0.05). Among the 38 patients with different degrees of abdominal pain,22 patients improved better than before;15 of 28 patients with different degrees of ascites were better than before. All patients had no serious complications related to treatment.Conclusions: Iodine-125 radioactive seed implantation therapy can safely and effectively treat hepatocellular carcinoma, and relieve the clinical symptoms of abdominal pain and ascites.

DTI and pathological changes in a rabbit model of radiation injury to the spinal cord after ^(125)I radioactive seed implantation

Excessive radiation exposure may lead to edema of the spinal cord and deterioration of the nervous system. Magnetic resonance imaging can be used to judge and assess the extent of edema and to evaluate pathological changes and thus may be used for the evaluation of spinal cord injuries caused by radiation therapy. Radioactive ^125I seeds to irradiate 90% of the spinal cord tissue at doses of 40–100 Gy （D90） were implanted in rabbits at T10 to induce radiation injury, and we evaluated their safety for use in the spinal cord. Diffusion tensor imaging showed that with increased D90, the apparent diffusion coefficient and fractional anisotropy values were increased. Moreover, pathological damage of neurons and microvessels in the gray matter and white matter was aggravated. At 2 months after implantation, obvious pathological injury was visible in the spinal cords of each group. Magnetic resonance diffusion tensor imaging revealed the radiation injury to the spinal cord, and we quantified the degree of spinal cord injury through apparent diffusion coefficient and fractional anisotropy.

Dosimetry for ^(125) I radioactive seed implantation therapy for hepatocellular carcinoma

Hepatocellular carcinoma （HCC） is an aggressive malignancy. Early lesions respond well to hepatic resection or liver transplantation. However, only a few of HCC patients are suitable for surgical intervention. External beam radiation and chemotherapy is poorly efficacious. In the last 20 years, HCCs belonging to the radiosensitive tumor group has been confirmed. Along with the development of new radiotherapy technology and facilities, the research about brachytherapy（especially ^125I seed implantation therapy） has provoked more interests in the world. Radioactive seed implantation therapy is a form of interstitial brachytherapy, with the property of local ＂conformal radiotherapy＂ and the advantages of minimal invasion, convenience, high performance, and minimal adverse effects. It is a promising therapy for HCC, however the dosimetry hasn＇ t yet been identified and lacks verification in prospective research. This report aims to further explore the best prescription dose and radioactivity for ^125I interstitial implantation brachytherapy for HCC.

^(125)I放射性粒子植入治疗复发性腭部小唾液腺恶性肿瘤7例临床分析

目的:探讨^(125)I放射性粒子植入治疗复发性腭部小唾液腺恶性肿瘤的临床效果。方法:对7例手术+放疗后复发且拒绝二次手术的腭部小唾液腺恶性肿瘤患者进行^(125)I放射性粒子植入治疗,根据患者具体情况制定治疗计划,术中将^(125)I放射性粒子植入设计的靶区组织间,术后视情况戴用赝复体式放射性粒子布源器。定期随访,观察治疗效果及不良反应。结果:7例患者随访17~62个月,均未见肿瘤再次复发,未出现明显3级及以上放射性损伤。随访过程中,1例高龄患者因全身疾病死亡,3例患者出现轻度暂时性不良反应。结论:对于复发的腭部小唾液腺恶性肿瘤,^(125)I放射性粒子植入治疗近期疗效良好,是一种安全、微创、有效的治疗方案。

Study of the Positioning Influence in the Water Activity Measurement during Leak Test of Iodine-125 Seeds

In the prostate cancer treatment, brachytherapy with iodine-125 seeds has been used. lodine-125 seeds are sealed radioactive sources, made by a titanium capsule containing the radioisotope inside. In the final phase of the seeds production, it is necessary to ensure that there is no leakage of the radioactive material. A leakage test is performed, immersing the seeds in water during 24 h and measuring the resulting activity in the water. This measurement is made in a sodium iodide detector. The immersion water is transferred to a plastic tube with a cap. The tube is placed by an automated positioning system, in the detector chamber. This study aims to determine the best positioning of the tube for the detection. It is also important to determine the influence of the positioning variation intrinsic of the automated positioning system during the iodine-125 seeds production. The results obtained will be used as a reference to adjust the equipment and process control system, in the production of the iodine-125 seeds.

碘125粒子植入治疗胰腺癌的现状

胰腺癌作为一种临床上常见的恶性程度极高的恶性肿瘤,通常有着起病隐匿,早期诊断困难,病情发展迅速等特点,预后较差。正是由于胰腺癌的这些特点,患者常常出现因确诊较晚而失去根治手术的机会,因此需要寻找其他替代治疗方案。放疗是治疗晚期癌症的常用方法,在胰腺癌的临床治疗中应用广泛,但其对病灶周围组织容易造成不同程度的损害而产生相应并发症,伴随着医疗技术的发展,临床上出现了粒子植入近距离组织内放射治疗的方案,而其中碘125粒子植入近距离放疗因其安全性和有效性颇受欢迎,本文综述了碘125粒子植入治疗的作用,碘125粒子植入治疗的应用,碘125粒子植入的不足与优势。

^(125)I粒子永久性植入组织间放射治疗肝癌

目的 :探讨12 5I组织间放射治疗肝癌的疗效。方法 :选择肝癌患者 84例 ,随机分为对照组 (A组 )与治疗组 (B组 ) ,A组 4 2例行手术治疗 (根治手术或姑息手术 )和化疗 ;B组 4 2例 ,除施行A组的治疗方案外 ,另行术中永久植入12 5I粒子。结果 :术前、术后 1w及 3个月内血象虽有显著差异 ,但均在正常范围内 ,免疫指标前后变化无统计学意义。A组 :12个月、2 4个月、36个月局部复发率分别为 4 1.7%、5 0 .0 %和 5 9.5 % ;12个月、2 4个月、36个月局部生存率分别为 81.3%、6 3.4 %和 4 7.6 %。B组 :12个月、2 4个月、36个月局部复发率分别为 0、6 .7%和 11.9% ;生存率分别为 94 .7%、87.5 %和 78.4 % ,两组的局部复发率及生存率有显著性差异 (P <0 .0 5 )。结论 :12 5I组织间放射治疗肝癌方法简单、安全 ,近期疗效确切 ,是治疗癌症的理想方法之一。