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1.
肝细胞癌(HCC)是最常见的原发性肝脏恶性肿瘤,手术切除及肝移植被认为是目前HCC可能的治愈方法,但仅30%~40%的患者能够受益。体部立体定向放射消融治疗(SABR)是近几年应用于体部恶性肿瘤治疗的一种新的精确放疗技术,以"少分次、大剂量"改变了传统的剂量分割模式,因其提高了体部恶性肿瘤的局部控制率、延长了总生存时间而受到重视。射波刀(CK)完成的SABR放疗技术具有高精度、无创伤的优点,可完成实时追踪照射(很好地解决了肿瘤的呼吸移动对治疗的影响),获得了理想的治疗有效率和局部无进展生存率、总生存率,同时3级以上放疗毒性反应发生率很低,是一种理想的治疗技术,为进一步提高HCC的临床疗效带来了新的希望。  相似文献   

2.
The treatment of advanced hepatocellular carcinoma (HCC) associated with portal vein tumor thrombosis (PVTT) is very challenging because of HCC's grave prognosis. Despite many efforts to improve the treatment results, patient survival has been limited to several months. In this situation, radiotherapy has been considered as an alternative treatment modality because of the growth of knowledge about the radiotolerance of normal tissue and the advances of radiotherapy techniques such as three dimensional conformal radiotherapy, intensity modulated radiotherapy, stereotactic body radiotherapy and proton therapy. More restoration of the liver function and longer survival of the patients can be achieved by the better response after radiotherapy. However, considering the high risk of intrahepatic advanced tumor or extrahepatic dissemination by PVTT at disease presentation, a combination of radiation therapy and systemic agents will be desirable. Therefore, performing prospective randomized clinical trials is important to assess the benefits of radiotherapy and to develop combination treatment strategies.  相似文献   

3.
Dose‐volume parameters are needed to guide the safe administration of stereotactic ablative radiotherapy (SABR). We report on esophageal tolerance to high‐dose hypofractionated radiation in patients treated with SABR. Thirty‐one patients with spine or lung tumors received single‐ or multiple‐fraction SABR to targets less than 1 cm from the esophagus. End points evaluated include D5cc (minimum dose in Gy to 5 cm3 of the esophagus receiving the highest dose), D2cc, D1cc, and Dmax (maximum dose to 0.01 cm3). Multiple‐fraction treatments were correlated using the linear quadratic and linear quadratic‐linear/universal survival models. Three esophageal toxicity events occurred, including esophagitis (grade 2), tracheoesophageal fistula (grade 4–5), and esophageal perforation (grade 4–5). Chemotherapy was a cofactor in the high‐grade events. The median time to development of esophageal toxicity was 4.1 months (range 0.6–6.1 months). Two of the three events occurred below a published D5cc threshold, all three were below a D2cc threshold, and one was below a Dmax threshold. We report a dosimetric analysis of incidental dose to the esophagus from SABR. High‐dose hypofractionated radiotherapy led to a number of high‐grade esophageal adverse events, suggesting that conservative parameters to protect the esophagus are necessary when SABR is used, especially in the setting of chemotherapy or prior radiotherapy.  相似文献   

4.
In the United States, more than half of all new invasive cancers diagnosed are non-small cell lung cancer, with a significant number of these cases presenting at locally advanced stages, resulting in about one-third of all cancer deaths. While the advent of stereotactic ablative radiation therapy (SABR, also known as stereotactic body radiotherapy, or SBRT) for early-staged patients has improved local tumor control to >90%, survival results for locally advanced stage lung cancer remain grim. Significant challenges exist in lung cancer radiation therapy including tumor motion, accurate dose calculation in low density media, limiting dose to nearby organs at risk, and changing anatomy over the treatment course. However, many recent technological advancements have been introduced that can meet these challenges, including four-dimensional computed tomography (4DCT) and volumetric cone-beam computed tomography (CBCT) to enable more accurate target definition and precise tumor localization during radiation, respectively. In addition, advances in dose calculation algorithms have allowed for more accurate dosimetry in heterogeneous media, and intensity modulated and arc delivery techniques can help spare organs at risk. New delivery approaches, such as tumor tracking and gating, offer additional potential for further reducing target margins. Image-guided adaptive radiation therapy (IGART) introduces the potential for individualized plan adaptation based on imaging feedback, including bulky residual disease, tumor progression, and physiological changes that occur during the treatment course. This review provides an overview of the current state of the art technology for lung cancer volume definition, treatment planning, localization, and treatment plan adaptation.KEYWORDS : Lung cancer, motion management, dose calculation, treatment planning  相似文献   

5.
20世纪90年代以来,随着放射物理技术、计算机技术和医学影像技术的迅猛发展,放射治疗技术已取得了长足进展。三维适形放疗、调强放疗、容积旋转调强放疗和螺旋断层放疗等先进放射治疗技术层出不穷,大幅提高了肿瘤靶区的物理适形度和治疗效率。但在肿瘤的放射治疗临床实践中仍然存在若干急需解决的问题。近年来,以生物引导放射治疗、图像引导放射治疗、剂量引导放射治疗和放射影像组学为代表的新技术,推动着放射治疗向以"精确定位"、"精确计划"和"精确治疗"为终极目标的"三精放疗"时代迈进。  相似文献   

6.
Many patients with hepatocellular carcinoma(HCC) present with advanced disease,not amenable to curative therapies such as surgery,transplantation or radiofrequency ablation. Treatment options for this group of patients include transarterial chemoembolization(TACE) and radiation therapy. Especially TACE,delivering a highly concentrated dose of chemotherapy to tumor cells while minimizing systemic toxicity of chemotherapy,has given favorable results on local control and survival. Radiotherapy,as a therapeutic modality of internal radiation therapy with radioisotopes,has also achieved efficacious tumor control in advanced disease. On the contrary,the role of external beam radiotherapy for HCC has been limited in the past,due to the low tolerance of surrounding normal liver parenchyma. However,technological innovations in the field of radiotherapy treatment planning and delivery,have provided the means of delivering radical doses to the tumor,while sparing normal tissues. Advanced and highly conformal radiotherapy approaches such as stereotactic body radiotherapy and proton therapy,evaluated for efficacy and safety for HCC,report encouraging results. In this review,we present the role of radiotherapy in hepatocellular carcinoma patients not suitable for radical treatment.  相似文献   

7.

Background/Aims

This study reports treatment outcomes after helical intensity-modulated radiotherapy (IMRT) in unresectable hepatocellular carcinoma (HCC) patients for whom transarterial chemoembolization (TACE) was considered ineffective or unsuitable.

Methods

From January 2008 to December 2011, 22 unresectable HCC patients received helical IMRT. A daily dose of 1.8 to 4 Gy was delivered at five fractions per week to deliver a total dose of 30 to 60 Gy. The most-prescribed dose fractionation was a total dose of 50 to 57.5 Gy, with a daily dose of 2.3 to 2.5 Gy.

Results

In the entire group, the objective response rate of the primary tumor was 72.7%. In the eight patients with portal vein thrombosis (PVT), the objective response rate of PVT was 50.0%. Median disease progression-free survival was 11.8 months, and the 1-year disease progression-free survival rate was 40.2%. The median overall survival was 14.4 months, and the 1- and 2-year overall survival rates were 86.4% and 69.1%, respectively. PVT and Child-Pugh classifications were significant prognostic factors for overall survival in multivariate analyses.

Conclusions

Helical IMRT in patients with unresectable HCC resulted in high treatment response and survival rates. This study suggests helical IMRT is a practical treatment option for HCC patients in whom TACE is unsuitable or ineffective.  相似文献   

8.
Systemic lupus erythematosus (SLE) is associated with major gastrointestinal complications due to radiotherapy. A patient with active SLE and grade 4 nephropathy presented with inoperable advanced cancer of the cervix which proved to be contraindicated for chemotherapy. The patient was treated with intensity-modulated radiotherapy technique (IMRT). The patient, however, did not experience severe radiotherapy-related complications as expected with conventional techniques of radiotherapy. The tolerance of SLE patients to radiotherapy can thus be achieved by proper delivery of radiation and the sparing of normal tissues by IMRT although further confirmatory studies are required.  相似文献   

9.
Stereotactic ablative radiotherapy (SABR), or stereotactic body radiotherapy (SBRT), has recently been applied in the field of arrhythmia management. It has been most widely assessed in the treatment of ventricular tachycardia (VT) but may also have potential in the treatment of other arrhythmias as well, often termed stereotactic arrhythmia radiotherapy (STAR). The non-invasive delivery of treatment for VT has the potential to spare an often physiologically vulnerable group of patients the burden of long catheter ablation procedures with the potential for prolonged periods of hemodynamic instability. Cardiac SABR also has the capacity to direct ablative therapy at substrate that is inaccessible using current transchatheter techniques. For these reasons cardiac SABR has generated significant enthusiasm as an emerging treatment modality for VT. We consider in review the pre-clinical data pertaining to the use of SABR in cardiac tissue and recent clinical evidence regarding the application of SABR in the field of arrhythmia management.  相似文献   

10.
AIM: To explore whether intensity modulated radiation therapy (IMRT) in combination with chemotherapy could increase radiation dose to gross tumor volume without severe acute radiation related toxicity by decreasing the dose to the surrounding normal tissue in patients with locally advanced pancreatic cancer. METHODS: Twenty-one patients with locally advanced pancreatic cancer were evaluated in this clinical trial. Patients would receive the dose of IMRT from 21Gy to 30Gy in 7 to 10 fractions within two weeks after conventional radiotherapy of 30Gy in 15 fractions over 3 weeks. The total escalation tumor dose would be 51, 54, 57, 60Gy, respectively. 5-fluororacil (5-FU) or gemcitabine was given concurrently with radiotherapy during the treatment course. RESULTS: Sixteen patients who had completed the radiotherapy plan with doses of 51Gy (3 cases), 54Gy (3 cases), 57Gy (3 cases) and 60Gy (7 cases) were included for evaluation. The median levels of CA19-9 prior to and after radiotherapy were 716 U/ml and 255 U/ml respectively (P<0.001) in 13 patients who demonstrated high levels of CA19-9 before radiotherapy. Fourteen patients who suffered from pain could reduce at least 1/3-1/2 amount of analgesic intake and 5 among these patients got complete relief of pain. Ten patients improved in Karnofsky performance status (KPS). The median follow-up period was 8 months and one-year survival rate was 35%. No patient suffered more than grade III acute toxicities induced by radiotherapy. CONCLUSION: Sixty Gy in 25 fractions over 5 weeks with late course IMRT technique combined with concurrent 5-FU chemotherapy can provide a definitely palliative benefit with tolerable acute radiation related toxicity for patients with advanced pancreatic cancer.  相似文献   

11.
In contrast to the conventional radiotherapy/chemoradiotherapy paradigms used in the treatment of majority of cancer types, this review will describe two areas of radiobiology, hyperfractionated and hypofractionated radiation therapy, for cancer treatment focusing on application of novel concepts underlying these treatment modalities. The initial part of the review discusses the phenomenon of hyper-radiation sensitivity (HRS) at lower doses (0.1 to 0.6 Gy), describing the underlying mechanisms and how this could enhance the effects of chemotherapy, particularly, in hyperfractionated settings. The second part examines the radiobiological/physiological mechanisms underlying the effects of high-dose hypofractionated radiation therapy that can be exploited for tumor cure. These include abscopal/bystander effects, activation of immune system, endothelial cell death and effect of hypoxia with re-oxygenation. These biological properties along with targeted dose delivery and distribution to reduce normal tissue toxicity may make high-dose hypofractionation more effective than conventional radiation therapy for treatment of advanced cancers. The novel radiation physics based methods that take into consideration the tumor volume to be irradiated and normal tissue avoidance/tolerance can further improve treatment outcome and post-treatment quality of life. In conclusion, there is enough evidence to further explore novel avenues to exploit biological mechanisms from hyper-fractionation by enhancing the efficacy of chemotherapy and hypo-fractionated radiation therapy that could enhance tumor control and use imaging and technological advances to reduce toxicity.KEYWORDS : Low Doses Fractionated Radiation Therapy (LDFRT), hyper-radiation sensitivity (HRS), induced radiation resistance (IRR), hyperfractionation, chemopotentiation, stereotactic body radiation therapy (SBRT), stereotactic ablative radiosurgery (SARS), stereotactic ablative radiotherapy (SABR), stereotactic radiosurgery (SRS), spatially fractionated GRID radiotherapy (SFGRT), lattice  相似文献   

12.
Advancements in imaging and radiotherapy (RT) techniques have allowed for remarkably precise delivery of high radiation dose per treatment fraction to intrathoracic targets. As a non-invasive therapeutic modality (compared to surgery), stereotactic body radiotherapy (SBRT) is an attractive option for patients with early-stage non-small cell lung cancers and oligometastases, especially for older patients with significant comorbidities and pre-existing pulmonary dysfunction. However, the outcomes and side effect profile of SBRT are highly dependent on tumor location, especially if the tumor is located centrally (within 2 cm of the proximal bronchial tree (PBT)] or ultracentrally (touching or within 1 cm of the mediastinum, esophagus, and PBT). In this focused review, we will examine the contemporary practice and principles of using hypofractionated RT or SBRT for central and ultracentral thoracic tumors. We will identify future directions on how this practice may be incorporated into the increasingly complicated modern paradigm of lung cancer treatments which now include immunotherapy along with proton beam radiotherapy.  相似文献   

13.
Stereotactic ablative radiotherapy (SABR) is a technique that has rapidly entered routine care for early-stage peripheral non-small cell lung cancer in many countries in the last decade. The adoption of SABR was partly stimulated by advances in the so-called 'image guided' radiotherapy delivery. In the last 2 years, a growing body of publications has reported on clinical outcomes, acute and late radiological changes after SABR, and sub-acute and late toxicity. The local control rates in many publications have exceeded 90% when tumors of up to 5 cm have been treated, with corresponding regional nodal failure rates of approximately 10%. However, these results are not universal: lower control rates reported by some authors serve to emphasize the importance of quality assurance in all steps of SABR treatment planning and delivery. High-grade toxicity is uncommon when so-called 'risk-adapted' fractionation schemes are applied; an approach which involves the use of lower daily doses and more fractions when critical normal organs are in the proximity of the tumor volume. This review will address the new data available on a number of controversial topics such as the treatment of patients without a tissue diagnosis of malignancy, data on SABR outcomes in patients with severe chronic obstructive airways disease, use of a classification system for late radiological changes post-SABR, late treatment-related toxicity, and the evidence to support a need for expert multi-disciplinary teams in the follow-up of such patients.  相似文献   

14.
Radiofrequency thermal ablation of hepatocellular carcinoma   总被引:5,自引:0,他引:5  
Hepatocellular carcinoma (HCC) is one of the major malignancies worldwide. Due to advanced or decompensated liver cirrhosis, comorbidity and multicentricity of the tumor lesions, 70-80% of HCC patients are inoperable at the time of diagnosis. Radiofrequency thermal ablation (RFTA) is a new minimally invasive and sage technique for the nonsurgical treatment of HCCs. Similar to other ablation techniques, the treatment strategy depends on several factors, including the patient's clinical status, the stage of liver cirrhosis and of the HCC. RFTA can be performed percutaneously, laparoscopically or after laparotomy. Advanced RFTA equipment, refined techniques of modifying tumor tissue response to RFTA, and combined treatment strategies should lead to better response rates even in larger HCCs.  相似文献   

15.
Background We have reported that proton radiotherapy for hepatocellular carcinoma (HCC) is a safe and effective therapeutic option. However, it is difficult to evaluate its effect in certain cases. Recently, it has been reported that the usage of contrast-enhanced color Doppler ultrasonography (CECDU) can improve diagnostic accuracy, both in terms of the presence of hepatic tumor and in the evaluation of treatment. The aim of this study was to determine the usefulness of CECDU in assessing the therapeutic response of HCC treated with proton radiotherapy.Methods Twenty-two patients treated with the proton radiotherapy were studied. We inspected HCC lesions by CECDU, before and after the irradiation, over time. The magnitude of blood flow in the HCC was quantified on still images by CECDU. The ratio of the number of color pixels against that of the total number of pixels in the tumor area was defined as the tumor blood flow ratio (TBFR).Results Immediately after the proton treatment, a transient increase of blood flow in the tumor was recognized in more than half of the patients, while the TBFR was unchanged or decreased in the remaining patients. At longer periods after irradiation, the TBFR in all HCCs gradually decreased, and this reduction of TBFR was statistically significant from 9 months after irradiation. These findings are consistent with those obtained previously by computed tomography (CT) as well as magnetic resonance imaging (MRI).Conclusions We propose CECDU as a useful diagnostic option for the evaluation of HCC treated with proton radiotherapy.Presented in part at the annual meeting of the American Gastroenterological Association in May 2001.  相似文献   

16.
Intensity-modulated radiotherapy (IMRT) is widely applied during the treatment of esophageal squamous cell carcinoma (ESCC), but the optimal radiation dose still lacks a consensus. The aim of this study was to explore the optimal radiation dose for inoperable locally advanced ESCC patients treated with IMRT in a real-world clinical setting.A total of 90 inoperable ESCC patients with locally advanced stages of II-IVA treated with IMRT in our institute between February 1, 2014 and June 30, 2019 were included in this retrospective study. Sixty patients had received >60 Gy (high dose group) and 30 patients had received ≤60 Gy (low dose group). The median radiation dose was 66 Gy (range: 61–70 Gy) and 50.2 Gy (range: 40–60 Gy), respectively. Concurrent chemotherapies were platinum-based regimens.The median progression free survival (PFS) and overall survival (OS) of all patients were 7.6 and 14.1 months, respectively. Patients in the high dose group exhibited a significantly better PFS (1-year PFS 34.6% vs 22.8%; 2-year PFS 11.9% vs 0%, P = .008) and OS (1-year OS 57.5% vs 39.5%; 2-year OS 31.4% vs 15.8%, P = .007). The median PFS in the high and low dose groups were 8.1 and 6.1 months, and the median OS were 15.4 and 8.5 months, respectively. Multivariate Cox analysis showed that radiation dose (>60 Gy vs ≤60 Gy) was independently prognostic factor for OS (HR: 0.44; 95% CI: 0.22–0.89; P = .021), but not for PFS (HR: 0.56; 95% CI: 0.31–1.02; P = .058). There was no significant difference in treatment-related toxicities of grade ≥3 between the 2 groups (P = .402).This retrospective study confirmed that higher radiation dose (>60 Gy) resulted in better survival outcomes for inoperable patients with locally advanced ESCC treated with IMRT.  相似文献   

17.
In view of the poor prognosis of patients with cholangiocarcinoma (CCC), there is a need for new therapeutic strategies. Inter-disciplinary therapy seems to be most promising. Radiotherapy is an effective alternative to surgery for hilar CCC (Klatskin tumors) if an adequate radiation dose can be delivered to the liver hilus. Here, we describe a patient for whom we used a stereotactic radiotherapy technique in the context of an inter-disciplinary treatment concept. We report a 45-year-old patient with a locally advanced Klatskin tumor. Explorative laparotomy showed that the tumor was not resectable. A metallic stent was implanted and the patient was treated by stereotactic radiotherapy using a body frame. A total dose of 48 Gy (3×4 Gy/wk) was administered. Therapy was well tolerated. After 32 mo, local tumor recurrence and a chest wall metastasis developed and were controlled by radio-chemotherapy. After more than 56 mo with a good quality of life, the patient died of advanced neoplastic disease. Stereotactic radiotherapy led to a long-term survival of this patient with a locally advanced Klatskin tumor. In the context of inter-disciplinary treatment concepts, this radiotherapy technique is a promising choice of treatment for patients with hilar CCC.  相似文献   

18.
The aim of this study was to compare high‐dose volumetric modulated arc therapy (VMAT) and fixed‐field intensity‐modulated radiotherapy (ff‐IMRT) plans for the treatment of patients with middle‐thoracic esophageal cancer. Eight patients with cT2‐3N0M0 middle‐thoracic esophageal cancer were enrolled. The treatment planning system was the version 9 of the Pinnacle3 with SmartArc (Philips Healthcare, Fitchburg, WI, USA). VMAT and ff‐IMRT treatment plans were generated for each case, and both techniques were used to deliver 50 Gy to the planning target volume (PTV50) and then provided a 16‐Gy boost (PTV66). The VMAT plans provided superior PTV66 coverage compared with the ff‐IMRT plans (P = 0.034), whereas the ff‐IMRT plans provided more appropriate dose homogeneity to the PTV50 (P = 0.017). In the lung, the V5 and V10 were lower for the ff‐IMRT plans than for the VMAT plans, whereas the V20 was lower for the VMAT plans. The delivery time was significantly shorter for the VMAT plans than for the ff‐IMRT plans (P = 0.012). In addition, the VMAT plans delivered fewer monitor units. The VMAT technique required a shorter planning time than the ff‐IMRT technique (3.8 ± 0.8 hours vs. 5.4 ± 0.6 hours, P = 0.011). The major advantages of VMAT plans are higher efficiency and an approximately 50% reduction in delivery time compared with the ff‐IMRT plans, with comparable plan quality. Further clinical investigations to evaluate the use of high‐dose VMAT for the treatment of esophageal cancer are warranted.  相似文献   

19.
BACKGROUND: Radiotherapy is often used to treat patients with unresectable advanced hepatocellular carcinoma (HCC). The present study examines the nature and frequency of adverse events with respect to liver function in such patients after radiotherapy. METHODS: Forty-six patients with HCC who underwent radiotherapy were retrospectively examined. Radiotherapy was applied using coplanar 2-3-beam arrangements to a target dose of 50 Gy/5 weeks. The adverse hepatic events were evaluated according to the National Cancer Institute Common Toxicity Criteria and the Radiation Therapy Oncology Group/European Organization for Research and Treatment of Cancer Late Radiation Morbidity Scoring Scheme during the acute phase and the late phase by following the patients for up to 1 year. The influence on survival by adverse hepatic events and other factors was analyzed. RESULTS: The full irradiation dose of 50 Gy was given to 40 patients (87.0%). Grade 3 or 4 toxicity was observed in 18 (39.1%) within 3 months after radiotherapy and in 11 (33.3%) of 33 thereafter, respectively. The most frequent and serious adverse events were hyperbilirubinemia, hypoalbuminemia, and ascites. The independent adverse prognostic factors for survival were portal vein tumor thrombus (P = 0.0012), tumor response (P = 0.011), acute adverse hepatic event (P = 0.012), and late adverse hepatic event (P = 0.015). CONCLUSIONS: Hypoalbuminemia, hyperbilirubinemia, and ascites were important hepatic adverse events that developed after applying radiotherapy to treat advanced HCC. These adverse events seriously affected survival.  相似文献   

20.
Intraoperative radiotherapy (IORT) allows delivery of radiotherapy doses in excess of those typically deliverable with conventional external beam radiotherapy. IORT has potential utility in clinical situations, such as treatment of esophageal and gastric malignancies, in which the radiation tolerance of normal organs limits the dose that can be given with conventional radiotherapy techniques. We reviewed the records of 50 patients who received IORT for locally advanced primary or recurrent gastric or esophageal adenocarcinomas deemed unresectable for cure. IORT was given as a single fraction of electron beam radiotherapy (10-25 Gy) after maximal tumor resection: R0 in 42%, R1 in 46%, and R2 in 12%. Forty-eight patients also received external beam radiotherapy (8-55 Gy), 46 received radiosensitizing chemotherapy, and nine received systemic chemotherapy after radiotherapy. Outcomes were estimated with Kaplan-Meier analysis. Median survival was 1.6 years. Overall survival at 1, 2, and 3 years was 70%, 40%, and 27%. Of 42 patients who died, 37 died from cancer progression and three from multifactorial treatment toxicity. Median survival for patients with recurrent disease versus primary disease was 3.0 years versus 1.3 years (P < 0.05), with a delay of metastatic failure in patients with recurrent tumors (P = 0.06). At 3 years, distant metastatic failure was 79%, local failure was 10%, and regional failure was 15%. IORT for locally advanced primary or recurrent gastric malignancies effectively decreases the risk of local failure. For patients with isolated local recurrences, IORT may be effective salvage therapy. However, more effective systemic therapy is needed as a component of treatment.  相似文献   

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