锥形束CT引导下应用SBRT治疗早期非小细胞肺癌疗效观察

目的:评价锥形束CT（cone beam CT,CBCT）引导下应用立体定向放射治疗（stereotactic body radiation therapy,SBRT）治疗早期非小细胞肺癌的近期疗效及毒副反应。方法:选取17例I期非小细胞肺癌患者接受CBCT引导下的SBRT胸部放疗,SBRT处方剂量DT 60 Gy/12 f,5次/周,95%以上计划靶区（PTV）满足处方剂量,90%等剂量线包含整个靶区,严格控制各危及器官剂量:双肺V5＜50%、V20＜20%,脊髓Dmax＜25 Gy,心脏Dmean＜27 Gy等。每次照射前均行CBCT扫描并在线匹配、校准。结果:所有患者均完成放疗并随访3～24个月（中位随访期18个月）,其中完全缓解（CR）4例,部分缓解（PR）12例,稳定（SD）1例,无进展患者,总有效率为94.1%。1年局部控制率和生存率分别为100%和100%。2年局部控制率和生存率分别为88.2%和82.3%。放疗期间未出现III级以上严重的放射性毒副反应。结论:应用CBCT引导下行SBRT治疗早期非小细胞肺癌,可显著提高其局部控制率和生存率,毒副反应较轻,但其远期疗效及晚期毒副反应仍待进一步随访观察。     

体部伽玛刀治疗头颈部腺样囊性癌多发肺转移瘤临床观察

 目的　观察体部伽玛刀治疗头颈部腺样囊性癌多发肺转移瘤的临床疗效。方法　对15例头颈部腺样囊性癌肺转移瘤患者共计137个病灶采用立体定向体部伽玛刀治疗。单次治疗病灶2～10灶,中位数5灶。以50 %剂量线为处方剂量线,单次照射剂量3～5 Gy,中位数4 Gy,1次／ d,5次／周,10～16次。肿瘤边缘总剂量30～52 Gy,中位数40 Gy。结果　137个病灶中,完全缓解58灶（42.3 %）,部分缓解64灶（46.7 %）,稳定15灶（10.9 %）,进展0灶,总有效率为89.1 %。治疗后1、2、3年局控率均为100.0 %。治疗后1、2、3、4、5年生存率分别为100.0 %、100.0 %、90.9 %、63.6 %、31.8 %。结论　体部伽玛刀治疗头颈部腺样囊腺癌多发肺转移瘤疗效较好,反应轻微,是一种安全有效的治疗手段。     

Four cases of meningeal hemangiopericytoma treated with surgery and radiotherapy.

We report our experiences of four cases with meningeal hemangiopericytoma treated with surgery and postoperative radiotherapy and survey the literature to elucidate the efficacy of radiotherapy. Patients were treated with surgical resection and 46-52 Gy postoperative radiotherapy. Three patients had local control for 30, 54 and 138 months, respectively and one patient had local recurrence after 49 months. Distant metastases were observed in two patients; one had multiple bone, liver and lung metastases and the other multiple bone and brain metastases. For bone and brain metastases, better tumor control was obtained with palliative radiotherapy and stereotactic radiotherapy. Literature analyses demonstrated that surgery and postoperative radiotherapy of 50 Gy or more resulted in significantly better local control than surgery alone (p = 0.02). Stereotactic radiosurgery was effective for intracranial recurrence or metastasis, especially when the tumor volume was <8 cm(3) and >15 Gy at the 50% isodose line was used. Radiotherapy for bone metastases was also effective for palliation.     

体部立体定向放疗治疗腹膜后转移瘤临床疗效观察

目的:观察全身γ刀立体定向放射治疗(SBRT)腹膜后转移瘤的近期疗效及不良反应.方法:采用超级γ刀（SGS-I型）立体定向放射治疗腹膜后转移癌65例,根据肿瘤的位置、临床靶体积、病人的身体状况与治疗目的,制定放射治疗计划及调整剂量分布.肿瘤体积8.7～1 352.3cm3,等剂量参考曲线50%～60%,周边照射总剂量40～48Gy,分割处方剂量4.0～6.0cGy,重复治疗8～10次,5次/周.结果:治疗前腰背部疼痛不适等40例,治疗结束后1至3个月,症状完全消失32例(80.0%),轻度缓解7例（17.5%）,部分缓解1例(2.5%),症状改善有效率为97.5%.65例病人治疗后2～3个月复查CT或MR,肿瘤消失36例(55.38%),缩小27例(41.54%),无变化2例(3.08%),总有效率96.92%.2级放射性消化系统反应为16.18%,无>2级放射性消化系统反应的发生.结论:全身γ刀治疗腹膜后转移癌临床效果确切,毒副反应较轻.     

体部立体定向放射治疗112例非小细胞肺癌近期疗效观察

目的观察立体定向放射治疗（SBRT）非小细胞肺癌的近期疗效和放射副反应。方法 112例非小细胞肺癌患者行伽玛刀放疗,50%的处方剂量线完全覆盖PTV,60%～70%剂量线包裹95%以上GTV,照射剂量以50%剂量线作为处方剂量,3～12 Gy/次,总剂量40～60 Gy,1～3周完成治疗。结果治疗后3～16个月所有患者得到随访,中位随访时间11个月,其中完全缓解（CR）率29.5%（33/112）,部分缓解（PR）率为60.7%（68/112）,总有效率为90.2%（101/112）。6个月和1年的局控率分别为98.8%（80/81）、92.3%（36/39）,生存率分别为100%（81/81）、94.9%（37/39）;放射性肺炎为其主要并发症,发生率为9.8%（11/112）。结论 LUNATM-260型伽玛刀作为1种新的SBRT设备,能够有效地提高非小细胞肺癌的局部控制率和生存率,且并发症发生率低。     

Analysis of suitable prescribed isodose line fitting to planning target volume in stereotactic body radiotherapy using dynamic conformal multiple arc therapy

PurposeTo assess the most suitable value of a relative prescribed dose in clinical treatment plans of stereotactic body radiotherapy (SBRT) using dynamic conformal multiple arc therapy to treat lung tumors.Methods and MaterialsWe retrospectively generated alternative SBRT plans for typical examples of 8 patients who had been treated with SBRT for a lung tumor with a prescribed dose of 50 Gy in 5 fractions. The prescribed dose had been defined as 80% of the maximal dose in the planning target volume (PTV) (“the 80% isodose plan”). Alternative 20%-90% isodose plans at 10% intervals were generated (64 plans; 8 plans for each of the 8 patients), and factors related to leaf margins, target volume, normal lung volume, and monitor units were compared using dose-volume histogram analysis.ResultsWe could generate all the 64 plans. Compared with the 80% isodose plan, the V20 and mean lung dose (MLD) were both lower in the 60% plan; the V20 was approximately 19% lower (4.72% vs 3.84%) and the MLD was 13% lower (4.0 Gy vs 3.5 Gy). Mean PTV and ITV doses were higher in the lower percentage isodose plans. Compared with the 80% isodose plan, in the 60% isodose plan the mean PTV was 19% higher (56.1 Gy vs 66.8 Gy) and the mean ITV was 30% higher (59.6 Gy vs 77.4 Gy). The mean total monitor units increased more steeply than did the mean homogeneity index. The mean conformity index values in the 60% and 70% isodose plans were less than 1.15.ConclusionsThe 60% isodose plan was considered the best plan in this analysis because of the lower comparative dosimetric factors in normal lung tissue (including V20 and MLD) and the higher comparative mean PTV and internal target volume doses achieved, along with good conformity index values. In clinical use, accurate estimation and commissioning should be performed for the dose distribution prior to selecting a plan. Further investigation is warranted to determine whether the calculated dosimetric advantages result in improved outcomes.     

体部伽玛刀治疗纵隔转移瘤54例近期疗效观察

目的观察评价体部伽玛刀治疗纵隔转移瘤的近期疗效和放射反应。方法采用体部伽玛刀治疗纵隔转移瘤54例。根据病灶位置、体积与治疗目的,制定治疗计划及调整剂量曲线分布。取50%～60%的等剂量线为处方剂量线,要求覆盖95%以上的计划靶区,70%的等剂量线覆盖肿瘤体积,3～5 Gy/次,5次/周,总剂量45～55 Gy/9～15次。结果所有患者均按计划完成治疗,2-3月复查CT或MRI,病灶完全缓解率74.1%(40/54),部分缓解率18.5%(10/54),无变化7.4%(4/54),无进展病例。急性放射性气管炎Ⅰ级25.9%(14/54),急性放射性食管炎Ⅰ级29.6%(16/54),Ⅱ级3.7%(2/54)。结论体部伽玛刀治疗纵隔转移瘤疗效肯定,是一种安全有效的局部治疗手段。     

Phase II trial of hypofractionated stereotactic radiotherapy for brain metastases: results and toxicity.

PURPOSE: To prospectively evaluate efficacy and side effects of hypofractionated stereotactic radiotherapy (hfSRT) for irresectable brain metastases not amenable to radiosurgery (SRS). METHODS AND MATERIALS: From 1/2003 to 2/2005, 51 patients with 72 brain metastases were included in a prospective phase II-trial and accepted for treatment at the dedicated stereotactic radiosurgery system Novalis (BrainLAB, Heimstetten, Germany). In case of planned or prior whole brain radiotherapy (WBRT), hfSRT was to be performed with 5 x 6 Gy, otherwise with 5 x 7 Gy. This dose was prescribed to the 90% isodose line which should cover 100% of the planning target volume (PTV). RESULTS: Rates of complete remission (CR), partial remission (PR), no change (NC) and progressive disease (PD) were 66.7%, 18.1%, 12.5% and 2.8%, respectively, after a median follow-up of 7 months. Median survival was 11 months. Disease-specific survival and survival related to brain metastases were strongly associated with the size of gross tumor volume (GTV), the planning target volume (PTV), Karnofsky Performance Score (KPS) and number of metastases. Side effects, i.e., increase in T2w-signal area, duration of steroid intake and size of new or progressive necrotic centre of metastasis, were dependent on the volume of normal brain irradiated with more than 4 Gy per fraction (V(4Gy)). Significantly more patients with a V(4Gy)> or =23 cc developed radiological signs of side effects from hfSRT. CONCLUSION: Hypofractionated stereotactic radiotherapy with 5 x 6-7 Gy is an effective and safe treatment for brain metastases not amenable to single high-dose radiosurgery. The normal brain volume receiving >4 Gy per fraction may not exceed 20 cc.     

立体定向适形放射治疗鼻咽癌复发或残留病变50例疗效分析

目的:探讨立体定向适形放射治疗对鼻咽癌放射治疗后残留病变或复发患者的临床疗效。方法:50例经根治放疗后的鼻咽癌复发或残留患者,全部采用WDVE-XKY808立体定向适形放射治疗。6MVX线总剂量DT30~48Gy,设1~4个中心,参考剂量曲线选定为70%~90%。4~6Gy/次,每次间隔1~3d。结果:肿瘤完全控制48例,无法评价2例,局部控制率为96%。1、2和3年总生存率分别为83·6%、65·0%和59·6%。1、2和3年无瘤生存率分别为75·0%、64·9%和54·1%。结论:立体定向适形放射治疗是鼻咽癌放射治疗后残留病变或复发患者“挽救性”治疗的适应证,有较好的局部控制效果和较高的安全性,是治疗复发或残留癌患者的有效方法之一。     

116例骨转移癌放射治疗止痛效果分析

[目的] 分析不同分割方式对转移性骨肿瘤放射治疗的止痛效果。[方法] 将116例骨转移癌患者分为3组，分别用50Gv／20次、26天，5次／周；28Gv／7次、9～ll天，5次／周；24Gv／4次、8～10天，3次／周的不同分割方式进行止痛放疗。[结果] 全组病例有效率(CR PR MR)为96．6％，3个剂量组的有效率依次为95．5%(2l／22)，97．5％(77／79)，9313％(14/15)。3组之间止痛效果无显著性差异。92％(103/112)的疼痛缓解出现在放疗后1～3周。[结论] 对骨转移癌进行局部止痛放疗是一种有效的对症治疗手段，研究的3种分割方式之间无明显疗效差异。     

Stereotactic Radiation Therapy for Renal Cell Carcinoma Brain Metastases in the Tyrosine Kinase Inhibitors Era: Outcomes of 120 Patients

BackgroundThe objective of the study was to evaluate the outcomes in terms of efficacy and safety of a large consecutive series of 362 patients with renal cell carcinoma (RCC) brain metastases treated using stereotactic radiosurgery (SRS) in the tyrosine kinase inhibitor (TKI) era.Patients and MethodsFrom 2005 to 2015, 362 consecutive patients with brain metastases from RCC were treated using SRS in 1 fraction: 226 metastases (61 patients) using Gamma-Knife at a median of 18 Gy (50% isodose line); 136 metastases (63 patients) using linear accelerator at a median of 16 Gy (70% isodose line). The median patient age was 58 years. At the first SRS, 37 patients (31%) received a systemic treatment. Among systemic therapies, TKIs were the most common (65%).ResultsThe local control rates were 94% and 92% at 12 and 36 months, respectively. In multivariate analysis, a minimal dose >17 Gy and concomitant TKI treatment were associated with higher rates of local control. The overall survival rates at 12 and 36 months were 52% and 29%, respectively. In multivariate analysis, factors associated with poor survival included age ≥65 years, lower score index for SRS, concomitant lung metastases, time between RCC diagnosis and first systemic metastasis ≤4 months, occurrence during treatment with a systemic therapy, no history of neurosurgery, and persistence or occurrence of neurological symptoms at 3 months after SRS. Seventeen patients had Grade III/IV adverse effects of whom 3 patients presented a symptomatic radionecrosis.ConclusionSRS is highly effective in patients with brain metastases from RCC. Its association with TKIs does not suggest higher risk of neurologic toxicity.     

体部伽玛刀治疗原发性大肝癌163例疗效分析

目的：探讨全身γ刀立体定向放射治疗原发性大肝癌的临床可行性及疗效。方法：采用超级γ刀（SGS-I型）立体定向放射治疗原发性大肝癌163例,根据肿瘤的位置、临床靶体积、病人的身体状况与治疗目的,制定放射治疗计划及调整剂量分布。肿瘤体积56.9-2697.0cm3,等剂量曲线50%-60%,周边照射总剂量33-40Gy,分割处方剂量3.3-5.0Gy,重复治疗8-12次,5次/周。结果：治疗前肝区胀痛不适等98例,治疗结束后1-3个月,症状完全消失59例（60.20%）,部分缓解30例（30.61%）,9例无效（9.18%）,症状改善有效率为90.82%;163例病人治疗后2-3个月复查CT或MR,肿瘤CR 17例（10.43%）,PR 79例（48.47%）,NC57例（34.97%）,PD 10例（6.13%）,总有效率93.87%。6个月和1年生存率分别为71.17%和58.90%。结论：全身γ刀立体定向放射治疗原发性大肝癌临床效果确切,副反应较轻。     

体部伽玛刀治疗原发性大肝癌163例疗效分析

目的:探讨全身γ刀立体定向放射治疗原发性大肝癌的临床可行性及疗效。方法:采用超级γ刀(SGS-I型)立体定向放射治疗原发性大肝癌163例,根据肿瘤的位置、临床靶体积、病人的身体状况与治疗目的,制定放射治疗计划及调整剂量分布。肿瘤体积56.9-2697.0cm3,等剂量曲线50%-60%,周边照射总剂量33-40Gy,分割处方剂量3.3-5.0Gy,重复治疗8-12次,5次/周。结果:治疗前肝区胀痛不适等98例,治疗结束后1-3个月,症状完全消失59例(60.20%),部分缓解30例(30.61%),9例无效(9.18%),症状改善有效率为90.82%;163例病人治疗后2-3个月复查CT或MR,肿瘤CR 17例(10.43%),PR 79例(48.47%),NC57例(34.97%),PD 10例(6.13%),总有效率93.87%。6个月和1年生存率分别为71.17%和58.90%。结论:全身γ刀立体定向放射治疗原发性大肝癌临床效果确切,副反应较轻。     

吉非替尼联合立体定向放疗一线治疗高龄非小细胞肺癌的临床观察

目的探讨吉非替尼联合立体定向放疗一线治疗高龄非小细胞肺癌的疗效和安全性。方法84例高龄非小细胞肺癌患者按治疗方法分为4组：A组25例,吉非替尼联合立体定向放射治疗;B组32例,单用立体定向放射治疗;C组12例,单用吉非替尼治疗;D组15例,对症治疗。吉非替尼均采用治疗第1天开始口服,每日250mg,直到病变进展或其他原因停药。立体定向放射治疗均从治疗第1天开始,等剂量曲线为50%～80%,单次周边剂量4.0～6.5Gy,治疗总剂量为36～48Gy,治疗次数8～12次,6次/周。结果2个月CT复查肿瘤病灶,A组肿瘤病灶治疗有效率（RR）为68.0%（17/25）,疾病控制率（DCR）为92.0%（23/25）,中位生存时间（MST）为11.8个月（范围3～21个月）,1年生存率为48.0%（12/25）,治疗期间常见副反应为皮疹、腹泻;B组RR为56.3%（18/32）,DCR为84.4%（27/32）,MST为7.2个月（范围3～16个月）,1年生存率为12.5%（4/32）;C组RR为33.3%（4/12）,DCR为58.3%（7/12）,MST为8.9个月（范围2～18＋个月）,1年生存率为33.3%（4/12）,治疗期间常见副反应为皮疹、腹泻;D组MST为4.8个月（范围2～10个月）,1年生存率为0。吉非替尼联合立体定向放射治疗组在近期疗效（RR及DCR）方面高于单用吉非替尼治疗组（P=0.046,P=0.014）,在远期疗效（1年生存率）方面高于单用立体定向放射治疗组（P=0.003）。结论吉非替尼联合立体定向放疗一线治疗高龄非小细胞肺癌具有较好的近期及远期疗效,毒性可耐受。     

Image-guided hypofractionated small volume radiotherapy of non-small cell lung cancer - feasibility and clinical outcome

Purpose: Local hypofractionated stereotactic radiation treatment (hfSRT) of early stage non-small cell lung cancer (NSCLC) represents a highly effective treatment alternative in medically inoperable patients. Method: Between June 2007 and December 2010, 65 patients with NSCLC were treated with image-guided hypofractionated radiotherapy. The Union Internationale Contre le Cancer (UICC) stage distribution was: IA, n = 19; IB, n = 15; IIB, n = 5; IIIA, n = 10; IIIB, n = 6; and IV, n = 10. The fractionation schedule used was 3 × 12.5 Gy (n = 36) prescribed to the encompassing 67% isodose line for peripheral primary tumours, and 8 × 6 Gy (n = 26) or 8 × 5 Gy (n = 3) prescribed to the encompassing 80% isodose line for centrally located tumours. Results: Mean follow-up was 13.8 months (range 1-41 months). Until now 6 patients developed a local recurrence, 2 of them in combination with mediastinal lymph node failure. The 1-year actuarial local control rate was 93% and overall survival 79%. Pneumonitis was seen in 14 patients (21.5%) (Common Terminology Criteria for Adverse Events (CTCAE) grade I: n = 12, and II: n = 2) after a median time period of 9.5 months. No patient developed pneumonitis of CTCAE grade III or higher. Conclusion: Image-guided hfSRT is effective and feasible in patients with non-operable NSCLC, even in higher stages, whenever local control is crucial and there are contraindications against systemic therapy.     

Stereotactic ablative body radiation therapy with dynamic conformal multiple arc therapy for liver tumors: Optimal isodose line fitting to the planning target volume

PurposeTo assess optimal relative prescribed dose values in stereotactic ablative body radiation therapy (SABR) using dynamic conformal multiple arc therapy (DCMAT) for liver tumors.Methods and MaterialsWe generated SABR plans for 8 typical liver tumors that received SABR with 50 Gy in 5 fractions. The prescribed dose had previously been defined as 80% of the maximal dose (“80% isodose plan”). Alternatively, 20%-90% isodose plans were created to compare dosimetric factors.ResultsThe mean liver volume values (%) that received > 20 Gy (V20) and the mean liver dose were both the lowest with a 70% isodose plan and were the second lowest with a 60% isodose plan. The V20 dose was 5.19% lower (11.14%) with a 70% isodose plan and 4.51% lower (11.22%) with a 60% isodose plan compared with the value with an 80% isodose plan (11.75%). Mean planning target volume (PTV) dose increased as the % isodose decreased. The mean PTV dose was 10% higher (62.4 Gy) with a 70% isodose plan and 21% higher (68.9 Gy) with a 60% isodose plan compared with the value with an 80% isodose plan (56.8 Gy).ConclusionsDuring SABR treatment planning using DCMAT for liver tumors, target doses increased as the percentage isodose value decreased, which could result in better outcomes. In contrast, a 70% isodose plan had the lowest normal liver dose and a 60% isodose plan had the second lowest. An optimal percentage isodose level might be adjusted depending on tumor radiation sensitivity and liver function reserve. Further investigation is warranted to determine whether these dosimetric advantages result in improved outcomes.     

Transient enlargement of contrast uptake on MRI after linear accelerator (linac) stereotactic radiosurgery for brain metastases

Purpose/Objective: With the increasing number of patients successfully treated with stereotactic radiosurgery for brain metastases, decision making after therapy based on follow-up imaging findings becomes more and more important. Magnetic resonance imaging (MRI) is the most sensitive means for follow-up studies. The objective of this study was to investigate the treatment outcome of our radiosurgery program and to describe the response of brain metastases to contrast-enhanced MRI after linear accelerator (linac) stereotactic radiosurgery and identify factors to distinguish among local control and local failure.

Methods and Materials: Using serial MRI, we followed the course of 87 brain metastases in 48 consecutive patients treated between September 1996 and November 1997 with linac-based radiosurgery with 15-MV photons. Treatment planning was performed on an MR data cube. For spherical metastases, radiosurgery was delivered using a 9 noncoplanar arc technique with circular-shaped collimators. For irregularly shaped targets, radiosurgery was delivered using a manually driven multi-leaf collimator with a leaf width of 1.5 mm projected to the isocenter. Median radiosurgery dose was 20 Gy prescribed to the 80% isodose. Together with whole brain radiotherapy (20 × 2 Gy, 5/w), a median radiosurgical dose of 15 Gy was delivered. Median follow-up was 8 (range 2–36) months. Factors influencing local control and survival rates were analyzed with respect to MRI response, and Kaplan-Meier curves were calculated.

Results: Actuarial local tumor control was 91% at one and two years. Patient survival at one and two years was 30% and 18%. Median survival was 9 months. During follow-up in 70 (81%) of the 87 treated metastases, the contrast-enhancing volumes on T1W images were stable or disappeared partly or completely. A transient enlargement of contrast-enhancing volumes was observed in 11 (12%) of the 87 lesions treated, while a progressive enlargement due to local treatment failure was observed in 6 (7%) of the 87 treated metastases. Younger age, early contrast onset after radiosurgery, and previous chemotherapy were associated with this transient enlargement of contrast-enhancing lesion volume.

Conclusions: Linac-based radiosurgery is an effective, noninvasive, and safe treatment option for patients with brain metastases. A marked enlargement of the contrast-enhancing volume on T₁-weighted MR images after radiosurgery is a sensitive predictor for, but not equivalent with, local failure. In as many as two-thirds of the cases with contrast enlargement in MRI follow-up, the contrast enlargement is transient with no need for further treatment. While some MRI findings are more likely if transient enlargement is present, a clear decision cannot be made based on MRI, and ultimately the clinical status dictates further action.     

Factors important for efficacy of stereotactic body radiotherapy of medically inoperable stage I lung cancer. A retrospective analysis of patients treated in the Nordic countries

We reviewed results of SBRT treatment of 138 patients with medically inoperable stage I NSCLC treated during 1996-2003 at five different centres in Sweden and Denmark. Mean age was 74 years (range 56-90) with 69 men and 72 women. SBRT was delivered using a 3D conformal multifield technique and a stereotactic body frame. Doses delivered were 30-48 Gy (65% isodose at the periphery of planning target volume, PTV) in 2-4 fractions. Equivalent dose in 2 Gy fractions (EQD2) was in the range of 50-100 Gy. Mean gross tumour volume (GTV) was 39 cm3 (2-436), and planning target volume was 101 cm3 (11-719). Overall response rate (CR, PR) was 61% (84/138). SD was noted in 36% (50/138). During a median follow-up period of 33 months (1-107), 16 (12%) local failures occurred, ten of which also included distant metastases. Local failure was associated with tumour size, target definition and central or pleura proximity. Distant metastases occurred in 25% (35/138) of the patients. Ninety-one (65%) patients died during follow-up of which 55 patients (60%) died of other causes than lung cancer. Three- and 5-year overall survival was 52 and 26% respectively. Lung cancer specific 3- and 5-year overall survival was 66 and 40% respectively. Fifty nine percent (83/138) of the patients had no side effects. Fourteen patients experienced grade 3-4 toxicity according to radiation therapy oncology group (RTOG). EQD2 (> v.s.<55.6 Gy) showed a statistically significant benefit survival for the higher doses. SBRT for stage I NSCLC results in favourable local control not inferior to fractionated RT and with acceptable toxicity.     

超级伽玛刀的临床应用及创新特点探讨

目的探讨超级γ刀对全身肿瘤治疗的临床可行性及近期疗效。方法采用超级γ刀（SGS-I型）立体定向放射治疗全身肿瘤患者536例,2.8～5.0Gy/次,1次/天,5次/周,计划靶区边缘（50%～80%等剂量线处）总剂量28～40Gy。分析其疗效并阐述其工作原理和创新特点。结果99例颅脑肿瘤治疗的有效率为90.9%;304例体部肿瘤治疗后3月复查CT、MRI或PET,肿瘤消失48例（15.8%）,缩小188例（61.8%）,无变化44例（14.5%）,增大24例（7.9%）,总有效率为92.1%,不良反应较轻。结论超级γ刀治疗肿瘤的适用范围广,安全、有效。