Clinical observation of gemcitabine and concomitant three-dimensional conformal radiotherapy in the treatment of locally advanced non-small cell lung cancer

Objective： To evaluate the clinical effect of gemcitabine and concurrent three-dimensional conformal radiation therapy （3D-CRT） for locally advanced non-small cell lung cancer （NSCLC）. Methods： From April 2002 to June 2005, 38 patients with inoperable stage Ⅲ NSCLC were treated with gemcitabine and 3D-CRT simultaneously. Chemotherapy consisted of intravenously gemcitabine 350 mg/m^2 on days 1, 8, 15, 22, 29, 36.3D-CRT was delivered up to a total dose of 60-64 Gy with a 2.0 Gy dose fraction per day, 5 days per week. Results： The overall response rates of primary tumor and mediastinum metastatic node were 86.8% （33/38） and 90.6% （29/32） respectively, and 91.7% （22/24） and 78.6% （11/14） for squamous cell carcinoma and adenocarcinoma respectively. The acute side effects of patients were mostly myelosuppression, nausea, vomiting, radiation-induced esophagitis and pneumonitis （RTOG 1/11）, however, all of them were cured. Conclusion： Concurrent application of gemcitabine and 3D-CRT can improve the overall response rate for locally advanced NSCLC without aggravating the side effects.

Influences of Motion Artifacts on Three-Dimensional Reconstruction Volume and Conformal Radiotherapy Planning

Objective ：To investigate the influences of motion artifacts on three-dimensional （3D） reconstruction volume and conformal radiotherapy planning. Methods： A phantom which can mimic the clip motion of lung tumor along the cranial-caudal direction is constructed by step motor, small ball of polyethylene and potato. Ten different scan protocols were set and CT data of the phantom were acquired by using a commercial GE LightSpeedl6 CT scanner. The 3D reconstruction of the CT data was implemented by adopting volume-rendering technology of GE AdvantageSim 6.0 system. The reconstructed volumes of each target in different scan protocols were measured through 3D measuring tools. Thus, relative deviations of the reconstruction volumes between moving targets and static ones were determined. The three-dimensional conformal radiation therapy （3D- CRT） plans and conformal fields were created and compared for a static/moving target with the WiMRT treatment planning system （TPS）. Results：For a static target, there was no obvious difference among the 3D reconstruction volumes when the CT data were acquired with different pitches and slices. The appearance of 3D reconstruction volume and 3D conformal field of a moving target was quite different from that of static one. The maximum relative deviation is nearly 90% for a moving target scanned with different scan protocols. The relative deviations are variable among the different targets, about from -39.8% to 89.5% for a smaller target and from - 18.4% to 20.5% for a larger one. Conclusion ：The motion artifacts have great effects on 3 D-CRT planning and reconstruction volume, which will greatly induce distorted conformal radiation fields and false DVHs for a moving target.

Analysis of the efficacy and safety of conventional radiotherapy of chest wall and clavicular field and three-dimensional conformal radiotherapy in patients after modified radical mastectomy

Objective:To explore the efficacy and safety of conventional radiotherapy of chest wall and clavicular field and three-dimensional conformal radiotherapy in patients after modified radical mastectomy.Methods: A total of 84 patients who were admitted in our hospital after modified radical mastectomy were included in the study and divided into the conventional radiotherapy group (n=42) and the three-dimensional conformal radiotherapy group (n=42) according to different radiotherapy methods. The patients in the conventional radiotherapy group were given conventional radiotherapy of chest wall and clavicular field, while the patients in the three-dimensional conformal radiotherapy group were given three-dimensional conformal radiotherapy. The serum tumor markers and peripheral blood T lymphocyte subsets 6-8 weeks after treatment in the two groups were detected. The clinical efficacy, and toxic and side effects in the two groups were evaluated.Results: The serum CA15-3, CA125, CEA, and CK19 levels after treatment in the two groups were significantly reduced when compared with before treatment, CD3+,CD4+, and CD4+/CD8+ were significantly elevated, while CD8+ was significantly reduced when compared with before treatment, but the comparison of the above indicators between the two groups was not statistically significant. The occurrence rate of radioactive skin damage and pneumonia after treatment in the conventional radiotherapy group was significantly higher than that in the three-dimensional conformal radiotherapy group. Conclusions:The two kinds of radiotherapy schemes have an equal efficacy, but the toxic and side effects of three-dimensional conformal radiotherapy are significantly lower than those by the conventional radiotherapy, with a certain advantage.

Helical tomotherapy and volumetric modulated arc therapy:New therapeutic arms in the breast cancer radiotherapy

AIM To analyse clinical and dosimetric results of helical tomotherapy(HT) and volumetric modulated arc therapy(VMAT) in complex adjuvant breast and nodes irradiation.METHODS Seventy-three patients were included(31 HT and 42 VMAT). Dose were 63.8 Gy(HT) and 63.2 Gy(VMAT) in the tumour bed, 52.2 Gy in the breast, 50.4 Gy in supraclavicular nodes(SCN) and internal mammary chain(IMC) with HT and 52.2 Gy and 49.3 Gy in IMC and SCN with VMAT in 29 fractions. Margins to particle tracking velocimetry were greater in the VMAT cohort(7 mm vs 5 mm).RESULTS For the HT cohort, the coverage of clinical target volumes was as follows: Tumour bed: 99.4% ± 2.4%; breast: 98.4% ± 4.3%; SCN: 99.5% ± 1.2%; IMC:96.5% ± 13.9%. For the VMAT cohort, the coverage was as follows: Tumour bed: 99.7% ± 0.5%, breast: 99.3% ± 0.7%; SCN: 99.6% ± 1.4%; IMC: 99.3% ± 3%. For ipsilateral lung, Dmean and V20 were 13.6 ± 1.2 Gy, 21.1% ± 5%(HT) and 13.6 ± 1.4 Gy, 20.1% ± 3.2%(VMAT). Dmean and V30 of the heart were 7.4 ± 1.4 Gy, 1% ± 1%(HT) and 10.3 ± 4.2 Gy, 2.5% ± 3.9%(VMAT). For controlateral breast Dmean was 3.6 ± 0.2 Gy(HT) and 4.6 ± 0.9 Gy(VMAT). Acute skin toxicity grade 3 was 5% in the two cohorts.CONCLUSION HT and VMAT in complex adjuvant breast irradiation allow a good coverage of target volumes with an acceptable acute tolerance. A longer follow-up is needed to assess the impact of low doses to healthy tissues.

Study of the impact of CT/CT image fusion radiotherapy on V_(20) and radiation pneumonitis of non-small cell lung cancer

Objective:The aim of our study was to investigate the value of CT/CT image fusion radiation treatment planning in non-small cell lung cancer(NSCLC) and the impact on V20 and radiation pneumonitis(RP).Methods:Patients who were pathologically or cytologically diagnosed of stage IIIA and IIIB NSCLC were treated with three-dimensional conformal radiation therapy(4000 cGy).Forty patients got at least 25% tumor reduction were randomly divided into two groups:group A of regular shrink field radiotherapy(20 cases) and group B of CT/CT image fused shrink field radiotherapy(20 cases).Dosage reached 6600 cGy.Clinical data,V20 and RP were observed within 3 months after radiotherapy.Statistical analysis was conducted for the NSCLC patients.Results:22.5%(9/40) patients got RP during follow-up.Group A accounted for 6 cases(30%),and group B had 3 cases(15%).There was no marked difference between the two groups(P = 0.256),univariate analysis revealed that the IV20 of A and B groups,and IV20 and CV20 of all patients were statistically related to the incidence of RP(P < 0.05).With Wilcoxon method assay,the ipsilateral lung V20 and contralateral lung V20 had statistical significance between the two groups(P < 0.05).Conclusion:The CT/CT image infusion treatment planning could increase the radical dosage with better tumor control probability but won't increase adverse reaction.

The Effect of Absorbed Dose to Organs at Risk Following Craniospinal Irradiation Using Different Radiotherapy Techniques

Introduction: In medulloblastoma patients craniospinal irradiation is an important element the treatment. Our study aimed to evaluate the effect of absorbed dose to organs at risk using the hybrid intensity-modulated radiation therapy (IMRT) versus three-dimensional conformal radiotherapy (3DCRT) for craniospinal irradiation (CSI) in average risk medulloblastoma patients. Materials and Methods: In this study, thirteen medulloblastoma patients were included. The prescribed total dose to the planning target volume (PTV) was 23, 40 Gy in 13 fractions. Two radiotherapy techniques, three dimensional conformal radiotherapy (3DCRT) and hybrid intensity modulated radiotherapy (IMRT) were used to treat these patients. The coverage of the Target was evaluated using the D mean, D95%, D2%, D98% and V95%. Other parameters were also compared such as Integral dose (ID), Homogeneity index (HI) and doses to the organs at risk (OARs). Results: There was no significant difference in the mean dose received by the PTV-Brain or the dose received by 95% and 98% of PTV volume using the two techniques. For PTV-Spine, the percentage volume receiving 95% of the total dose increased significantly in the hybrid IMRT technique compared to the conformal technique. So, hybrid IMRT plan achieved the best coverage for PTV spine. Lower dose for OAR was delivered by 3DCRT, except the heart and thyroid, hybrid IMRT achieved better sparing. All plans resulted in the same dose homogeneity index (DHI) for PTV-Brain. For PTV-Spine, hybrid IMRT technique achieved better dose homogeneity compared to 3DCRT technique (1.09 vs. 1.12;p > 0.05). Conclusions: hybrid IMRT technique can be realized on conformal technique because it achieved better dose coverage for the (PTV) and organ at risk (OAR). 3DCRT reduced mean dose to most OARS, except the heart and thyroid. Therefore, the hybrid IMRT technique may be a CSI treatment alternative to 3DCRT.

The impact of intensity modulated radiotherapy on the skin dose for deep seated tumors

Objective: The purpose of this study was to investigate the impact of intensity modulated radiotherapy (IMRT) on surface doses for brain, abdomen and pelvis deep located tumors treated with 6 MV photon and to evaluate the skin dose calculation accuracy of the XIO 4.04 treatment planning system. Methods: More investigations for the influences of IMRT on skin doses would increase its applications for many treatment sites. Measuring skin doses in real treatment situations would reduce the uncertainty of skin dose prediction. In this work a pediatric human phantom was covered by a layer of 1 mm bolus at three treatment sites and thermoluminescent dosimeter (TLD) chips were inserted into the bolus at each treatment site before CT scan. Two different treatment plans [three-dimensional conformal radiation therapy (3DCRT) and IMRT] for each treatment sites were performed on XIO 4.04 treatment planning system using superposition algorism. Results: The results showed that the surface doses for 3DCRT were higher than the surface doses in IMRT by 1.6%, 2.5% and 3.2% for brain, abdomen and pelvis sites respectively. There was good agreement between measured and calculated surface doses, where the calculated surface dose was 15.5% for brain tumor calculated with 3DCRT whereas the measured surface dose was 12.1%. For abdomen site the calculated surface dose for IMRT treatment plan was 16.5% whereas the measured surface dose was 12.6%. Conclusion: The skin dose in IMRT for deep seated tumors is lower than that in 3DCRT which is another advantage for the IMRT. The TLD readings showed that the difference between the calculated and measured point dose is negligible. The superposition calculation algorism of the XIO 4.04 treatment planning system modeled the superficial dose well.

Simultaneous modulated accelerated radiation therapy for esophageal cancer:A feasibility study

AIM: To establish the feasibility of simultaneous modulated accelerated radiation therapy (SMART) in esophageal cancer (EC).

512例鼻咽癌颈淋巴结转移规律的研究

背景与目的:合理定义鼻咽癌颈部靶区在临床上显得越来越重要,本研究旨在探讨鼻咽癌颈淋巴结转移的规律,以指导三维适形放射治疗颈部靶区的勾画。方法:收集2003年1月～2004年6月在中山大学肿瘤防治中心初治的鼻咽癌病例512例,所有病例均经病理证实、并行增强CT模拟扫描。淋巴结分区标准采用2003年RTOG推荐的颈部淋巴结分区标准。结果:512例病例中,328例(64.1%)诊断为有淋巴结转移。淋巴结阳性的病例中61.3%为单侧淋巴结转移,38.7%为双侧淋巴结转移。咽后淋巴结的发生率为64.1%,其中单侧占50.9%,双侧占49.1%。淋巴结阳性的病例中Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ和咽后区的转移率分别为3.0%、97.9%、46.0%、9.5%、13.7%、0%和74.4%。跳跃性转移率仅为4.6%～6.5%。25.3%的N1-3病例出现了推荐标准以外区域的侵犯。结论:鼻咽癌的颈部淋巴结转移是由上而下循序性的;跳跃性转移发生率低;咽后淋巴结为鼻咽癌转移的首站淋巴结。咽后、Ⅱ区和Ⅲ区最容易受累及;Ⅰa和Ⅵ区从未受累。有部分阳性淋巴结超出了RTOG推荐用于N0的颈部CTV范围。以上结果有助于鼻咽癌的三维适形放疗和调强放疗颈部靶区的勾画。

单纯性适形放疗中晚期原发性肝癌的疗效评价

目的初步评价单纯性立体定向适形放射治疗技术应用于中晚期肝癌的临床疗效.方法立体定向适形放射治疗系统治疗198例原发性中晚期肝癌患者,6 MV x射线使90%等剂量曲线包绕100%的剂量体积,照射剂量48～63 Gy/6～9 f,共12～18 d.结果治疗后不同阶段复查CT.198例病人中,1个月后部分缓解41%(81/198),3个月后为48%(95/198),半年后94%(186/198),无变化为5%(10/198),进展为1%(2/198);门脉癌栓消退率65.6%(31/48).Ⅲ期肝癌病人1年生存率68%(40/59),2年生存率41%(24/59),3年生存率35%(21/59).3年生存的21例肝癌患者中,ⅢA期19例,ⅢB期2例.Ⅳ期肝癌治疗平均生存13个月,最长达25个月.43例治疗前肝功能正常的患者治疗后肝功能均无明显变化.155例肝功能不全的患者治疗后6个月肝功能较治疗前无显著差异性(P＞0.05).结论立体定向适形放射治疗是治疗中晚期肝癌有效的无创治疗手段.

68例高龄中晚期胃癌姑息性三维适形放疗结果分析

目的:总结3年来我科经病理证实的高龄中晚期胃癌患者接受三维适形放疗的长期随访数据,评价姑息性三维适形放射治疗对中晚期胃癌的价值。方法:回顾性分析我科2010年1月-2012年12月三维适形放疗的68例高龄中晚期胃癌患者的病理分期、放疗的靶区和剂量、放疗后病灶控制的情况、复发转移的情况及生存时间。结果:本组患者男44例,女24例,年龄54-83岁(平均64岁)。病理分期为T2-4N1-3M0-1。全部患者采用直线加速器三维适形放疗。放射靶区为胃癌病灶及胃左动脉淋巴结,放疗总剂量45-55Gy,6MV或15MV-X射线,每次2.0-2.5Gy,18-22次,每周5次。放疗后1-3个月86.4%(19/22)患者进食困难明显减轻或正常进食;91.3%(42/46)患者上腹部疼痛明显减轻。胃镜提示39.7%(27/68)患者胃部病灶缩小甚至消失;72.1%(49/68)患者腹部CT提示胃部病灶及胃左淋巴结缩小。放疗后CR 16.2%(11/68),PR61.7%(42/68)。本组患者生存期为3-18个月,中位生存期为13.5个月。放疗后4.4%(3/68)患者有轻-中度胃痛。结论:对中晚期胃癌三维适形放疗具有与手术类似的控癌作用,又能避免手术引起的创伤等不良反应,尤其是对已有周围脏器浸润的高龄、体质差的中晚期患者姑息性三维适形放射治疗可起到局部肿瘤控制、镇痛、改善生存质量、延长生存期的作用。但姑息性三维适形放疗的靶区确定、治疗剂量的选择以及综合治疗方面尚需进一步研究。

三维适形放疗联合射频热疗治疗中晚期食管癌的疗效观察

目的探讨三维适形放疗联合射频热疗治疗中晚期食管癌的疗效。方法 48例中晚期食管癌随机分成2组,每组24例。单纯放疗组:DT 2 Gy/次,共30～35次,6～7周完成;综合治疗组:DT 2 Gy/次,共30～35次,6～7周完成,放疗期间加用HY7000-1型射频热疗,每周2次,功率500～800 W,每次加热1 h,共6次。结果综合治疗组的近期有效率为95.8%,明显高于单纯放疗组的70.8%,差异有统计学意义(P<0.05)。结论三维适形放疗联合射频热疗能提高中晚期食管癌的近期治疗效果。

三维适形放疗联合射频热疗治疗食管上段癌的临床观察

目的分析三维适形放疗联合射频热疗治疗食管上段癌的疗效,与单纯放疗作对比。方法48例食管上段癌随机分2组,每组24例。单纯放疗组：DT 60-70 Gy/30-35次/6-7周;综合治疗组：DT 60-70 Gy/30-35次/6-7周,放疗期间加用SR-1000型射频热疗,每周两次,功率500-800 W,每次加热1 h,共6次。结果综合治疗组的近期疗效（CR＋PR）为95.8%,明显高于单纯放疗组的70.8%,差异有统计学意义（P〈0.05）。结论联合方法即三维适形放疗＋射频热疗能提高食管癌的近期治疗效果。

支架置入联合三维适形放疗治疗中晚期食管癌19例疗效观察

目的探讨X线透视下支架置入联合三维适形放疗治疗中晚期食管癌的临床疗效。方法对19例食管癌患者,应用金属支架置入联合三维适形放疗,对其临床疗效进行回顾性分析。结果支架植入术后可显著缓解患者吞咽困难;联合放疗后病灶明显退缩,生活质量显著改善;6个月、1年及2年生存率分别为84.2%(16/19)、57.9%(11/19)、21.1%(4/19)。结论支架置入联合放疗是治疗中晚期食管癌患者吞咽困难的有效方法,可显著提高患者生活质量及近期疗效。

模拟呼吸运动对SBRT剂量分布的影响研究

目的研究模拟呼吸运动对不同单次大剂量体部立体定向放疗(SBRT)剂量分布的影响。方法选取2018年1~6月来武汉大学人民医院肿瘤中心治疗的20例肿瘤最大径5 cm的肺癌SBRT患者,每例肺癌都设计七野三维适形和调强适形两组计划,分别对单次剂量为200、400、600、800、1000 cGy进行研究。将美国Sunnuclear公司生产二维半导体阵列Mapchecker置于运动平板上,使用近似运动周期T为3.5 s,跟常人呼吸运动周期相似,运动幅度为±5、±10、±15 mm;比较模拟呼吸运动和静止状态下治疗计划系统输出的相应等中心处水平面剂量分布和实测的剂量分布差异,两组间数据行配对t检验。结果不同运动幅度和不同单次剂量的SBRT三维适形与调强适形计划放疗剂量分布γ分析通过率(3%/3 mm)比较,差异有高度统计学意义(P < 0.01)。结论呼吸运动会导致肿瘤靶区剂量的适形度降低,导致放射剂量分布更加模糊;通过Mapchecker系统软件很容易分析出呼吸运动对3DCRT剂量分布的影响主要集中在靶区头脚方向,可对IMRT的影响分布于整个靶区;同一运动幅度随单次剂量的提高,调强放疗的剂量分布通过率反而比三维适形高。

化疗配合后程适形放疗治疗食管癌67例疗效分析

目的:探讨化疗(DF方案)配合后程适形放疗对食管癌治疗的价值。方法:将134例食管癌患者随机分为2组进行研究。综合组67例,化疗配合后程适形放疗;单放组64例,行单纯放射治疗(后程适形放疗)。结果:综合组与单放组1、2、3年生存率分别为66%、48%、36%和42%、30%、16%。综合组1、2、3年生存率高于单放组(P<0.05),远地转移率综合组低于单放组(P<0.05),局控率两组差异无显著意义(P>0.05),治疗副反应患者尚能耐受。结论:化疗配合后程适形放疗治疗食管癌优于单纯后程适形放疗。

直肠癌术后复发患者行三维适形放疗加同步化疗的实验研究

目的:探讨三维适形放疗治疗直肠癌术后复发的优越性。方法:选取直肠癌术后复发需行放疗的患者60例,随机分为常规放疗组和三维适形放疗组,每组30例,两组均给予同步化疗,对比两组生存率、放化疗反应发生率及严重程度。结果:与常规放疗组比较,三维适形放疗组可明显提高患者第1,3年生存率(P<0.05),且可降低放射性皮肤反应,消化道、泌尿系放疗反应两组比较差异无统计学意义(P>0.05)。结论:对于术后复发的直肠癌患者行三维适形照射优于以往常规照射方式。

不同周期TPF方案诱导化疗加顺铂同期调强适形放疗对中晚期鼻咽癌的疗效

目的观察不同周期TPF方案诱导化疗后加顺铂同期调强适形放疗(IMRT)对中晚期鼻咽癌的临床疗效及不良反应。方法 98例局部晚期鼻咽癌患者行TPF方案诱导化疗2周期或3周期,放疗采用IMRT技术,放疗期间予顺铂同步化疗2周期,21 d为1周期。比较TPF方案诱导化疗2周期与3周期患者疗效和不良反应。结果 TPF方案诱导化疗2周期与3周期患者的临床疗效及不良反应比较差异均无统计学意义(P>0.05)。结论 TPF方案诱导化疗2周期或3周期,然后联合顺铂同期IMRT治疗中晚期鼻咽癌,临床疗效和不良反应相近,增加诱导化疗周期在提高疗效方面尚未表现出明显优势。

Ⅰ期乳腺癌保乳术后乳腺三维适形加速外照射的临床研究

目的探讨Ⅰ期乳腺癌保乳术后乳腺三维适形加速外照射(APBI-3DCRT)治疗的近期疗效。方法选择2003年2月至2006年3月在湖北省肿瘤医院行Ⅰ期乳腺癌保乳术后患者89例,自愿接受APBI-3DCRT治疗的患者57例为APBI-3DCRT组,全乳腺照射(WBI)治疗的患者32例为WBI组。使用8 MV光子线进行APBI-3DCRT和WBI计划设计,设定4～5个照射野,处方剂量为每次3.4 Gy,每天2次,间隔6 h,总剂量34 Gy。观察两组患者的生存率、复发率、急性放射性损伤发生率和乳房美容效果。结果 APBI-3DCRT组急性放射性皮肤反应发生率和肺损伤发生率(10.53%和5.26%)较WBI组(28.13%和18.75%)低(P<0.05)。APBI-3DCRT组乳房美容优良率(92.98%)较WBI组(75.00%)高(P<0.05)。结论Ⅰ期乳腺癌保乳术后APBI-3DCRT治疗近期疗效好。

以顺铂为基础的不同化疗方案同步三维适形放疗对放射性肺炎的影响

目的探讨以顺铂为基础的不同化疗方案同步三维适形放射治疗局部晚期非小细胞肺癌（NSCLC）对放射性肺炎的影响。方法回顾性分析120例局部晚期NSCLC，所有患者均接受了以顺铂为基础的联合化疗同步三维适形放射治疗，按化疗方案的不同分为EP（顺铂和足叶乙苷）方案组（57例）、NC（顺铂和多西他赛）方案组（41例）和DC（顺铂和长春瑞滨）方案组（22例），观察3组放射性肺炎的发生、转归及其影响因素。结果1＋2级放射性肺炎EP方案组为33．3％（19／57），NC方案组为29．3％（12／41），高于DC方案组[22．7％（5／22）]；≥3级放射性肺炎发生率EP方案组为10．5％（6／57），NC方案组为9．7％（4／41），DC方案组为4．5％（1／22）；但是3组在发生放射性肺炎级别程度上差异无统计学意义（P〉0．05），经治疗后3组发生放射性肺炎患者的转归差异无统计学意义（P〉0．05）。结论以顺铂为基础的化疗方案同步三维适形放射治疗局部晚期NSCLC发生放射性肺炎是可以耐受的，接受顺铂和多西他赛、足叶乙苷、长春瑞滨联合化疗对放射性肺炎影响的差异无统计学意义。但多西他赛能提高肺的耐受性，具有较强的放射增敏效应，对于老年且合并慢性阻塞性肺疾病的患者可考虑优先多西他赛化疗，以减少放射性肺炎的发生。