脑胶质瘤伽玛刀放射外科治疗的临床初步观察

目的：探讨伽玛刀治疗对脑胶质瘤的临床疗效及反应。方法：自2002年7月至2008年12月对604例病理诊断明确的脑胶质瘤患者进行了伽玛刀治疗,其中男358例,女246例,年龄5-80岁,平均46.2岁。病理诊断：星形细胞瘤411例（68%）,其中Ⅰ-Ⅱ级262例,（63.7%）,Ⅲ-Ⅳ级149例（36.3%）。室管膜瘤55例（9.1%）,少枝胶质细胞瘤93例（15.4%）,脉络丛乳头状瘤14例（2.3%）,髓母细胞瘤31例（5.1%）。肿瘤周边剂量为8-30Gy,平均15.4Gy,中心剂量为25-62.5Gy,平均40.2Gy。结果：随访时间为6至60个月,平均19个月。低度恶性胶质瘤的疗效明显优于高度恶性胶质瘤（P〈0.005）,伽玛刀治疗的总有效率为82.8%。低度恶性胶质瘤生存期大于高度恶性胶质瘤,生存1年以上和生存2年以上均有显著性差异,（P〈0.005）。结论：伽玛刀对低恶性胶质瘤患者的治疗效果优于高恶性胶质瘤,并且能有效延长生存时间,提高生存质量。对体积较小,脑深部或脑干胶质瘤,伽玛刀能有效杀死肿瘤细胞并延缓肿瘤生长。     

脑胶质瘤伽玛刀放射外科治疗的临床初步观察

目的:探讨伽玛刀治疗对脑胶质瘤的临床疗效及反应.方法:自2002年7月至2008年12月对604例病理诊断明确的脑胶质瘤患者进行了伽玛刀治疗,其中男358例,女246例,年龄5-80岁,平均46.2岁.病理诊断:星形细胞瘤411例(68%),其中Ⅰ-Ⅱ级262例,(63.7%),Ⅲ-Ⅳ级149例(36.3%).室管膜瘤55例(9.1%),少枝胶质细胞瘤93例(15.4%),脉络丛乳头状瘤14例(2.3%),髓母细胞瘤31例(5.1%).肿瘤周边剂量为8-30Gy,平均15.4Gy,中心剂量为25-62.5Gy,平均40.2Cy.结果:随访时间为6至60个月,平均19个月.低度恶性胶质瘤的疗效明显优于高度恶性胶质瘤(P<0.005),伽玛刀治疗的总有效率为82.8%.低度恶性胶质瘤生存期大于高度恶性胶质瘤,生存1年以上和生存2年以上均有显著性差异,(P<0.005).结论:伽玛刀对低恶性胶质瘤患者的治疗效果优于高恶性胶质瘤,并且能有效延长生存时间,提高生存质量.对体积较小,脑深部或脑干胶质瘤,伽玛刀能有效杀死肿瘤细胞并延缓肿瘤生长.     

Clinical outcome after repeated radiosurgery for brain arteriovenous malformations

Introduction

We assessed the clinical and radiological outcome after repeated radiosurgery for brain arteriovenous malformations (bAVMs) after failure of initial radiosurgery.

Materials and methods

Fifteen patients underwent repeated radiosurgery. The mean bAVM volume at first radiosurgery (S1) was 4.6 ± 4.3 ml and that at second radiosurgery (S2) was 2.1 ± 2.5 ml. The median marginal dose was 18 Gy at S1, and 21 Gy at S2. Modified Rankin Scale (MRS) score was determined in all patients at last follow-up (FU).

Results

Complete obliteration was reached in nine patients (60%). Median time to obliteration was 50 months after S2. An excellent outcome (no new neurologic deficiencies, complete obliteration) was reached in seven patients (47%). Eleven patients (73%) showed a MRS ? 1. Radiation-induced complications occurred in 20%, of which 13% occurred after S2. Radiological complications included cyst formation (n = 1), radiation-related edema (n = 4), and radiation necrosis (n = 1), resulting in an increasing mean MRS of 0.5 at S1, 0.6 at S2, to 0.8 at FU. No (re-)bleedings were encountered during 137-patient years at risk.

Discussion

Repeated radiosurgery is a viable option for the treatment of small remnant bAVMs. We report 20% permanent radiation-induced complications. Such complications were mainly seen in relatively large, and therefore difficult to treat, bAVMs.     

Clinical results of 24 pituitary macroadenomas with linac-based stereotactic radiosurgery

Purpose: To determine the impact of stereotactic radiosurgery (SRS) on the clinical course, hormonal status, and follow-up CT/MRI scan of pituitary macroadenomas.Methods and Materials: From July 1988 to March 1996, 24 pituitary macroadenomas had been treated using 6 MV linear accelerator based SRS. They consisted of 11 (45.8%) prolactinomas, 2 (8.3%) growth hormone (GH)-secreting tumors, 1 (4.2%) Cushing’s disease, 8 (33.3%) nonsecreting (nonfunctioning: NF) tumors, and 2 (8.3%) mixed prolactin-growth hormone (PRL-GH)-secreting tumors (M:F = 12:12; aged 21–61 years). Postoperative irradiation was performed in all cases except for the instance of Cushing’s disease. The prescribed dose to tumor center varied from 10 to 27 Gy (mean 21.1 Gy) using a collimator size of 0.5 to 2.5 cm. The follow-up duration ranged from 13 to 89 months (mean 49.2 months). Results from these patients were compared to our results using conventional radiation.Results: Visual acuity and field defect were improved or became normal in 19 (79.2%) cases. Four (16.7%) remained unchanged after the treatment. One (4.1%) progressed 6 years after SRS and subsequently had repeat surgery with conventional boost irradiation. Of the 13 (46.4%) prolactinomas, including two mixed PRL-GH secreting tumors, 11 (84.1%) revealed normal hormonal levels within 1 year after SRS. In contrast, it took 2 years to become normal after conventional radiation therapy. In four GH-secreting tumors including two mixed PRL-GH secreting tumors, SRS and conventional methods showed similar responses. On follow-up imagings of the 21 patients, the mass was completely resolved in 4 (16.7%), including 3 PRLs and one NF, decreased in 11 (45.8%), and unchanged in 5 (16.7%) with central necrosis or cysts. One (4.2%) progressed and was reoperated 6 years after treatment. The complications related to SRS were comparable to those from conventional method.Conclusion: Radiosurgery can be used effectively in patients with pituitary adenoma. In this study, a more rapid hormonal and clinical response was achieved with radiosurgery than with conventional pituitary irradiation treatment.     

Clinical use of dual image-guided localization system for spine radiosurgery

The recently released Novalis TX linac platform provides various image guided localization methods including a stereoscopic X-ray imaging technique (ExacTrac) and a volumetric cone beam computed tomography (CBCT) imaging technique. The ExacTrac combined with the robotic six dimensional (6D) couch provides fast and accurate patient setup based on bony structures and offers "snap shot" imaging at any point during the treatment to detect patient motion. The CBCT offers a three dimensional (3D), volumetric image of the patient's setup with visualization of anatomic structures. However, each imaging system has a separate isocenter, which may not coincide with each other or with the linac isocenter. The aim of this paper was to compare the localization accuracy between Exactrac and CBCT for single fraction spine radiosurgery treatments. The study was performed for both phantom and patients (96 clinical treatments of 57 patients). The discrepancies between the isocenter between the ExacTrac and CBCT in four dimensions (three translations and one rotation) were recorded and statistically analyzed using two-tailed t-test.     

伽玛刀放射外科治疗49例颅咽管瘤的临床效果分析

目的:探讨伽玛刀放射外科治疗颅咽管瘤的临床效果和预后。方法:回顾性分析49例颅咽管瘤患者的临床资料，均给予伽玛刀放射外科治疗，肿瘤平均体积为2.75 cm3，边缘平均剂量为11.8 Gy。临床效果通过磁共振检查、神经内分泌学和下丘脑症状、并发症和KPS评分评价。结果:49例患者影像学检查,16例完全缓解，20例部分缓解，9例无变化，4例肿瘤进展。肿瘤反应率为69.4%，控制率为87.8%。使用11.8 Gy的边缘剂量治疗较小的颅咽管瘤，有更好的控制率且没有并发症发生。KPS评分100分24例，90分16例，70~80分4例，50~60分2例。Kaplan-Meier生存分析表明5年生存率为95.9%，10年生存率为87.8%。5年肿瘤无进展生存率为77.6%，10年肿瘤无进展生存率为73.5%。3例患者因肿瘤进展死亡。结论:在显微手术联合放射治疗后，肿瘤体积的减小和有效的放射剂量设定对于改善患者生活质量和生存至关重要。     

Clinical outcomes following salvage Gamma Knife radiosurgery for recurrent glioblastoma

Glioblastoma multiforme (GBM) is the most common malignant primary brain tumor with a survival prognosis of 14-16 mo for the highest functioning patients. Despite aggressive, multimodal upfront therapies, the majority of GBMs will recur in approximately six months. Salvage therapy options for recurrent GBM (rGBM) are an area of intense research. This study compares recent survival and quality of life outcomes following Gamma Knife radiosurgery (GKRS) salvage therapy. Following a PubMed search for studies using GKRS as salvage therapy for malignant gliomas, nine articles from 2005 to July 2013 were identified which evaluated rGBM treatment. In this review, we compare Overall survival following diagnosis, Overall survival following salvage treatment, Progression-free survival, Time to recurrence, Local tumor control, and adverse radiation effects. This report discusses results for rGBM patient populations alone, not for mixed populations with other tumor histology grades. All nine studies reported median overall survival rates (from diagnosis, range: 16.7-33.2 mo; from salvage, range: 9-17.9 mo). Three studies identified median progression-free survival (range: 4.6-14.9 mo). Two showed median time to recurrence of GBM. Two discussed local tumor control. Six studies reported adverse radiation effects (range: 0%-46% of patients). The greatest survival advantages were seen in patients who received GKRS salvage along with other treatments, like resection or bevacizumab, suggesting that appropriately tailored multimodal therapy should be considered with each rGBM patient. However, there needs to be a randomized clinical trial to test GKRS for rGBM before the possibility of selection bias can be dismissed.     

射波刀治疗局部晚期胰腺癌的临床疗效分析

背景与目的:射波刀(CyberKnife)是一种肿瘤立体定向放射外科治疗(SRS/SRT)领域的新技术,具有同步呼吸追踪、实时影像引导、无框架定位及高精确度等优势,近年来已被应用在全身肿瘤的治疗上。本文回顾性分析射波刀立体定向放射治疗局部晚期胰腺癌的临床疗效及其不良反应。方法:2009年03月—2010年08月,接受射波刀治疗的局部晚期胰腺癌32例,年龄45～79岁,临床分期Ⅱ期12例,Ⅲ期20例;胰头癌19例,胰体尾癌13例。胰腺癌计划靶体积29～124 cm3,中位52 cm3,计划靶体积为肿瘤体积外放2～3 mm,分割3～6次,总剂量40～55 Gy,中位剂量45 Gy,72%等剂量面必须包括95%以上计划靶体积。32例患者全部采用肿瘤内植入金标的同步呼吸追踪技术(Synchrony),治疗后评估疗效和不良反应。结果:所有患者治疗耐受性良好,主要不良反应表现为乏力、恶心、呕吐。随访时间4～30个月(中位时间16个月),12例患者存活,CT复查结果完全缓解(CR)6例,部分缓解(PR)17例,稳定(SD)6例,进展(PR)2例,有效率(CR+PR)为74.2%,1年生存率为53.1%。无3级血液学毒性及4级非血液学毒性发生。结论:采用射波刀进行立体定向放射治疗局部晚期胰腺癌近期疗效显著,安全性好,远期疗效需进一步随访。     

Clinical implementation of an automated planning system for gamma knife radiosurgery

PURPOSE: To evaluate an automated treatment planning system for gamma knife radiosurgery. This planning system was developed in our clinic and is now in routine clinical use. The system simultaneously optimizes the shot sizes, locations, and weights. It also guides the user in selecting the total number of radiation shots. METHODS AND MATERIALS: We assessed the clinical significance of the automated system by comparing an optimized plan with a manual plan for 10 consecutive patients treated at our gamma knife facility. Each treatment plan was analyzed using dose-volume histograms in conjunction with the conformity index, the minimum target dose, and the integral normal tissue dose. RESULTS: On average, the treatment plan produced by the inverse planning tool provided an improved conformity index, a higher minimum target dose, and a reduced volume of the 30% isodose line as compared to the corresponding plan developed by an experienced physician. An optimized treatment plan can typically be produced in 10 min or less. CONCLUSIONS: The automated planning system consistently provides a high-quality treatment plan while reducing the time required for gamma knife treatment planning.     

Clinical evaluation of targeting accuracy of gamma knife radiosurgery in trigeminal neuralgia

PURPOSE: The efficiency of radiosurgery is related to its highly precise targeting. We assessed clinically the targeting accuracy of radiosurgical treatment with the Leksell Gamma Knife for trigeminal neuralgia. We also studied the applied radiation dose within the area of focal contrast enhancement on the trigeminal nerve root following radiosurgery. METHODS AND MATERIALS: From an initial group of 78 patients with trigeminal neuralgia treated with gamma knife radiosurgery using a 90-Gy dose, we analyzed a subgroup of 65 patients for whom 6-month follow-up MRI showed focal contrast enhancement of the trigeminal nerve. Follow-up MRI was spatially coregistered to the radiosurgical planning MRI. Target accuracy was assessed from deviation of the coordinates of the intended target compared with the center of enhancement on postoperative MRI. Radiation dose delivered at the borders of contrast enhancement was evaluated. RESULTS: The median deviation of the coordinates between the intended target and the center of contrast enhancement was 0.91 mm in Euclidean space. The radiation doses fitting within the borders of the contrast enhancement of the trigeminal nerve root ranged from 49 to 85 Gy (median value, 77 +/- 8.7 Gy). CONCLUSIONS: The median deviation found in clinical assessment of gamma knife treatment for trigeminal neuralgia is low and compatible with its high rate of efficiency. Focal enhancement of the trigeminal nerve after radiosurgery occurred in 83% of our patients and was not associated with clinical outcome. Focal enhancement borders along the nerve root fit with a median dose of 77 +/- 8.7 Gy.     

Clinical outcomes of patients treated with a second course of stereotactic radiosurgery for locally or regionally recurrent brain metastases after prior stereotactic radiosurgery

Patients with metastatic disease are living longer and may be confronted with locally or regionally recurrent brain metastases (BM) after prior stereotactic radiosurgery (SRS) or fractionated stereotactic radiotherapy (FSRT). This study analyzes outcomes in patients without prior whole brain radiotherapy (WBRT) who were treated with a second course of SRS/FSRT for locally or regionally recurrent BM. We identified 32 patients at our institution who were treated with a second course of SRS/FSRT after initial SRS/FSRT for newly diagnosed BM. We report clinical outcomes including local control, survival, and toxicities. Control rates and survival were calculated using Kaplan–Meier analysis and the multivariate proportional hazards model. The Kaplan–Meier estimate of local control at 6 months was 77 % for targets treated by a second course of SRS/FSRT with 11/71 (15 %) targets experiencing local failure. Multivariate analysis shows that upon re-treatment, local recurrences were more likely to fail than regional recurrences (OR 8.8, p = 0.02). Median survival for all patients from first SRS/FSRT was 14.6 months (5.3–72.2 months) and 7.9 months (0.7–61.1 months) from second SRS/FSRT. Thirty-eight percent of patients ultimately received WBRT as salvage therapy after the second SRS/FSRT. Seventy-one percent of patients died without active neurologic symptoms. The present study demonstrates that the majority of patients who progress after SRS/FSRT for newly diagnosed BM are candidates for salvage SRS/FSRT. By reserving WBRT for later salvage, we believe that a significant proportion of patients can avoid WBRT all together, thus putting fewer patients at risk for neurocognitive toxicity.     

Clinical uses of prosthetic devices in brachiotherapy for oral cavity tumors

Three different acrylic resin intraoral stents used for radiotherapy are described. They serve multiple functions in the treatment of tumors of the oral cavity. They are prepared individually and are necessary for accurate treatment planning and in order to minimize the exposure of hospital personnel to radiation.     

Dynamic stereotactic radiosurgery

Two radiosurgical procedures using a stereotactic frame and a linear accelerator X ray beam with a circular field diameter between 0.5 and 3 cm are presented. One technique is based on a single plane rotation (single plane radiosurgery) whereas the other uses simultaneous and continuous motions of both the gantry (approximately 360 degrees) and couch (approximately 180 degrees) during the radiosurgical procedure (dynamic radiosurgery). The dose, typically a few thousand cGy, is prescribed to the 90% isodose line which just covers the target volume. The dose fall-off outside the spherical target volume is considerably sharper for the dynamic rotation than for the single plane rotation, and is comparable to the dose fall-off obtained with the two presently known dedicated radiosurgical techniques: one based on focused cobalt beams and the other on proton beams. The dose fall-off in the dynamic radiosurgery discussed here is also comparable to that of previously described linear accelerator based multiple converging are techniques, making the dynamic radiosurgery an attractive alternative to presently known radiosurgical procedures. The radiation beam parameters are discussed and the stereotactic frame described. The dose distributions for both radiosurgical techniques are calculated in a single plane and then corrected for the attenuation effects in the stereotactic frame (approximately 2%) and for the effects of the dynamic rotation (approximately 2%). The skin doses are 0.7% and 2%, and the lens doses, if the beam passes through the eyes, are 2.5% and 3.5% for the dynamic rotation and single plane rotation, respectively. The scatter and leakage dose for the radiosurgical procedures is typically 0.2% to the patient's thyroid, 0.06% to the breast, and 0.02% to the gonads.     

Gamma knife radiosurgery

Gamma knife radiosurgery has become a new treatment modality in the field of neurosurgery since the first gamma knife was brought into Japan in 1990. Advances in applications of new indications and long-term results have been continued to evolve during the past 12 years. Based on the experience of more than 4,500 cases treated by gamma knife at Komaki City Hospital, long-term results of arteriovenous malformations (AVMs), metastatic brain tumors, acoustic neurinomas, meningiomas and trigeminal neuralgias are presented. Radiosurgery has become a novel treatment modality, especially for AVM, acoustic neurinoma and meningioma, which were once only treatable by conventional surgery, and shows a high cure rate in AVM cases and high control rate in benign tumors without major complications. The effects of radiosurgery for metastatic brain tumors have been thought to be superior to fractionated radiotherapy due to high response and control rates, and patients showed improved quality of life although no prolongation of the life span was obtained. Gamma knife treatment for trigeminal neuralgia has been shown to be effective and less invasive than microvascular decompression, and is useful for cases resistant to conventional therapies and as an initial treatment as well.     

The Hutson loop and prosthesis: Clinical uses in hepato-biliary intervention

A number of method of making a Roux-en-Y hepaticojejunostomy have been advocated to help the radiologist gain access to the biliary system. We have found markers and rings unsatisfactory and therefore designed and tested our own prosthesis. Reliable rapid access is easily achieved using this device with a much reduced radiation dose to both patient and radiologist. The prosthesis has been used for the past 3 years, and the last 23 patients are reviewed. Seven patients have required repeated interventions via the loop and we present the findings and our results.     

Surgical resection and postoperative radiosurgery versus staged radiosurgery for large brain metastases

Journal of Neuro-Oncology - The purpose of this study was to retrospectively evaluate the new treatment paradigm of staged stereotactic radiosurgery (SRS) for the treatment of large brain...