Brachytherapy: An emblematic example of extreme hypofractionated regimen

In order to provide more convenient irradiation regimens for patient comfort, radiation facility organization and health expenses, new hypofractionated protocols have been evaluated. Moderately (dose/fraction: 2.3 to 3 Gy), then ultra (dose/fraction: 5.2 to 6.1 Gy) hypofractionated irradiations were first validated. The current question is: is it possible to go forward using extreme hypofractionated regimens (EHR) based on 1 to 3 fractions. Different irradiation techniques are under investigation. However, brachytherapy remains the smartest way to deliver a high dose in a small volume. We report prospective and retrospective study results which evaluated EHR for breast and prostate brachytherapy. While oncological outcome and toxicity profile appear extremely encouraging for low-risk breast cancer after a 1 to 4 fractions (6.25 to 20 Gy/fraction), the use of a single fraction of 19 to 23 Gy appears debatable for prostate cancer. Brachytherapy represents an emblematic example of EHR but longer follow-up and more mature results are awaited in order to specify the right indications and refine the EQD2 calculation method including new biological and technical factors.     

Ultrasound-guided Brachytherapy for Cervix Cancer

Radiotherapy and brachytherapy are the definitive treatments for locally advanced cervix cancer. The use of soft-tissue imaging, particularly magnetic resonance imaging, has enhanced their effectiveness and improved clinical outcomes. However, the use of magnetic resonance imaging is largely restricted to well-resourced centres in both the first and developing world and remains elusive to many less advantaged centres, particularly those in areas with a high burden of cervix cancer. Ultrasound is an accessible, affordable and accurate imaging modality that can be used throughout the brachytherapy procedure. Ultrasound is primarily used to ensure safe insertion of the applicator but can also be used to guide planning. The methods used to utilise ultrasound images for planning are described. Ultrasound is particularly useful as a verification aid to confirm applicator placement after patients are moved and transferred around the radiotherapy department. It can also be used to verify the dimensions of treatment volumes over the course of brachytherapy. There is a crucial unmet need for an accessible economical soft-tissue imaging modality in cervical brachytherapy. Ultrasound has the potential to meet this need.     

CT导向下125I种子源植入治疗恶性肿瘤

目的:探讨CT导向下125I种子源植入治疗恶性肿瘤的安全性及临床疗效。方法:11例患者14个病灶行CT导向下125I种子源植入,其中原发肿瘤5例,转移瘤6例(9个病灶)。根据治疗计划系统(TPS)计算布源,在CT导向下将18.5~29.6MBq活度的125I种子源相隔1.0~1.5cm多层面植入肿瘤内。术后1~10个月复查CT观察种子源在瘤体内的分布、疗效及有无并发症。结果:随诊CT复查,14个病灶完全缓解(CR)5个;明显缓解(OR)7个;部分缓解(PR)2个;无效(P)0。治疗前后病灶平均大小分别为4.23cm和2.07cm(t=5.018,P<0.01)。未见急性并发症和治疗相关的放射损伤。结论:CT导向下125I种子源植入治疗恶性肿瘤是一种安全、有效的方法,近期疗效肯定。     

Prototype system for an MR simulation of intracavitary brachytherapy for cervical cancer: Preliminary results in six cases

We report a newly developed MR simulation system for intracavitary brachytherapy for cervical cancer and subsequent treatment results. MR simulation was performed on six patients. The spatial relationship of the tumor to the bladder, rectum, bowel, applicators, etc. was depicted well. Doses to the tumor and surrounding normal tissues were read from isodose curves superimposed on the T2-weighted sagittal image. This system promises to be useful in customizing the dose distribution.     

125I粒子组织间种植对人胃癌裸鼠移植瘤的杀伤作用

目的 观察不同剂量^125I粒子对人胃癌裸鼠移植瘤的杀伤作用及组织损伤。方法 建立人胃癌BGC-823细胞裸鼠皮下移植瘤模型，随机分为对照组和实验组，将不同剂量（100、120、140Gy）地^125I粒子植于实验组。30、60d：比较移植瘤抑瘤率，病理组织学、局部皮肤反应、裸鼠体重及白细胞计数。结果30d，100、120、140Gy组抑瘤率分别为51．93％、79．18％、90．22％，病理组织学反应程度多为RCRG2（45．83％），各实验组组间除120Gy与140Gy（P〉O．05）组外，及分别与对照组比较，差异有统计学意义（P〈0．05）；局部皮肤反应各实验组与对照组比较，差异有统计学意义（P〈0．05），各实验组组间差异无统计学意义（P〉0．05）。60d，各组抑瘤率分别为97．97％、100％、96．69％，病理组织学反应程度以RCRG1居多（62．5％），与对照组比较，差异均有统计学意义（P〈0．05），各实验组组间差异无统计学意义（P〉0．05）；局部皮肤反应随剂量增高而加重，各实验组组间及其分别与对照组比较，差异有统计学意义（P〈0．05）。结论 不同剂量的^125I粒子在不同时间对人胃癌裸鼠皮下移植瘤有显著杀伤作用，但120Gy和140Gy组随剂量累积，损伤明显增加。提示100Gy可能是治疗人胃癌裸鼠皮下移植瘤的有效剂量。     

153Sm-citrate-HA滑膜切除术治疗类风湿关节炎患者57例近期疗效分析

目的观察^153 Sm-柠檬酸-羟基磷灰石（citrate—HA）滑膜切除术治疗类风湿关节炎（RA）所致膝关节滑膜增生的近期疗效。方法对57例RA患者103个有明显滑膜增生的膝关节行关节腔内注射^153 Sm—citrate．HA5×37MBq（0．5～1m1），比较治疗前后关节症状（疼痛、肿胀、积液、功能活动度、上下楼及蹲站受限）变化情况，按优效、良效、微效、无效4级标准评判疗效，并对不同X线分期患者的疗效进行分析。结果治疗后1周开始起效，在半年内疗效逐渐明显，患者关节症状逐渐减轻甚至消失；总有效率为98．1％，其中Ⅰ、Ⅱ期患者的优效率分别为100％和91．3％。结论^153 Sm-citrate—HA滑膜切除术对RA滑膜增生性变是一项简单、安全、有效的治疗方法。     

Malignant obstructive jaundice: treatment with external-beam and intracavitary radiotherapy

Eleven patients with obstructive jaundice from unresectable cholangiocarcinoma, metastatic porta hepatis adenopathy, or direct compression from a pancreatic malignancy were treated at the Stanford University Medical Center from 1978-1983 with an external drainage procedure followed by high-dose external-beam radiotherapy and by an intracavitary boost to the site of obstruction with Iridium192 (Ir192). A median dose of 5000 cGy was delivered with 4-6 Mv photons to the tumor bed and regional lymphatics in 9 patients, 1 patient received 2100 cGy to the liver in accelerated fractions because of extensive intrahepatic disease, and 1 patient received 7000 "equivalent" cGy to his pancreatic tumor bed and regional lymphatics with neon heavy particles. An Ir192 wire source later delivered a 3100-10,647 cGy boost to the site of biliary obstruction in each patient, for a mean combined dose of 10,202 cGy to a point 5 mm from the line source. Few acute complications were noted, but 3/11 patients (27%) subsequently developed upper gastrointestinal bleeding from duodenitis or frank duodenal ulceration 4 weeks, 4 months, and 7.5 months following treatment. Eight patients died--5 with local recurrence +/- distant metastasis, 2 with sepsis, and 1 with widespread systemic metastasis. Autopsies revealed no evidence of biliary tree obstruction in 3/3 patients. Mean survival time from initial laparotomy and bypass was 16.1 months, and from radiotherapy completion was 8.3 months. Evolution of radiation treatment techniques for biliary obstruction in the literature is reviewed. High-dose external-beam therapy followed by high-dose Ir192 intracavitary boost is well tolerated and provides significant palliation. Survival of these aggressively managed patients approaches that of patients with primarily resectable tumors.