经会阴实时超声图像引导技术在前列腺癌放疗中应用

目的 经会阴实时超声图像引导(TPUS)技术实时监测前列腺各分次内运动幅度,以期为前列腺癌的精确放疗和大分割放疗提供参考。方法 应用TPUS技术采集70例前列腺癌患者1 588个分次运动数据。每次放疗前均采用CBCT纠正分次间误差,采用VMAT技术放疗。放疗过程中实时采集超声图像(1次/s),获取出束时间内的前列腺左右(x轴)、头脚(y轴)、腹背(z轴)方向上的位移范围,整合时间因素分析前列腺四维运动轨迹。结果 全部患者均顺利完成治疗及数据采集。单次有效监测时间的中位值为179 s (132~286 s)。95%的监测时间内前列腺在各方向上的运动范围分别为左侧2.22 mm、右侧2.17 mm、头侧2.08 mm、脚侧1.98 mm、腹侧2.44 mm及背侧2.97 mm。放疗过程中前列腺在x、y、z轴的位移幅度<1 mm的时间占总时间的百分比分别为83.07%、85.46%和78.27%,<3 mm的时间占97.70%、97.87%和96.45%。结论 TPUS技术是一种无创的实时追踪技术,可探测到放疗过程中前列腺的四维运动轨迹,在采用VMAT技术放疗时,前列腺整体位移幅度较小,95%时间内各个方向的位移范围在3 mm以内。     

前列腺癌影像引导放疗中电子射野影像装置和经会阴超声实时位置验证方法比较

[目的]比较电子射野影像装置（electronic portal imaging device,EPID）和Clarity经会阴超声（trans-perineal ultrasound,TPUS）在基于黄金基准标志物的前列腺癌影像引导放疗（IGRT）中靶区实时位置验证效能。[方法]筛选符合标准的前列腺癌患者10例,接受治疗前锥形束CT验证以确保前列腺癌IGRT分次治疗间靶区位置准确性;之后接受治疗中实时EPID和TPUS成像,分别采用Bland-Altman法和独立样本t检验评价两种成像方法对前列腺癌IGRT分次治疗内靶区位置验证一致性和差异。[结果] TPUS和EPID位置验证数值在左右、头脚、腹背3个方向上具有中度以上相关性（r=0.879、0.645、0.531）。3个方向上TPUS位置验证数值显著性小于EPID[(0.32±0.20)mm vs (0.51±0.33) mm,(0.41±0.31) mm vs (0.63±0.48) mm,(0.46±0.38) mm vs (0.72±0.45) mm,P均<0.05]。TPUS和EPID记录的总位移时间呈弱相关（r=0...     

前列腺癌大分割精确放疗分次治疗间和分次治疗内位置变动分析

目的 了解前列腺癌精确大分割放疗时分次间和分次内前列腺靶区位移情况。方法 对 2013—2016年间28例接受5 Gy9次放疗的前列腺癌患者,定位前2周B超引导下经直肠穿刺前列腺内植入纯金标记3颗,仰卧位体膜固定充盈膀胱并直肠内插置直肠扩张球囊充气60 ml后CT定位,Pinnacle系统制定放疗计划。23例患者Synergy加速器治疗,每次疗前CBCT校位,扫描图像与计划图像行骨配准记录摆位误差,然后通过前列腺内金标位置配准记录前列腺位移误差,两次之差为分次间位移。5例患者Novalis加速器治疗,通过前列腺内金标配准,疗中ExacTrac系统实时跟踪金标位置变化,观察前列腺分次内位移。结果 23例患者每次疗前均测量位移共计207次,左右、上下、前后位移平均值分别为(0.05±0.10)、(0.20±0.22)、(0.19±0.18) cm;3个方向>0.3 cm位移分别为1、52、49次,>0.5 cm位移分别为1、29、16次。5例患者每次疗时监测测量金标位置移动5次共计225次,左右、上下、前后位移平均值分别为(0.61±0.50)、(0.68±0.69)、(0.70±0.67) mm,各方向>3 mm移动分别为0、1、1次。结论 前列腺癌精确大分割放疗时分次间位移远远大于分次内位移,分次间位移必须校正后才能放疗。分次内靶区位移尽管变化较小,但仍有必要监测分次内靶区位移,以防患者体位变动造成靶区脱靶照射。直肠内球囊插入对前列腺位置具有固定作用。     

三维超声在前列腺癌图像引导放疗中的应用与评价研究

目的以锥形束CT校准为金标准, 评价前列腺癌图像引导放疗中三维超声校准的准确度, 并分析影响其准确度的危险因素。方法选择2018年12月至2021年12月河北北方学院附属第一医院放疗科51例前列腺癌患者为研究对象。患者均接受每周3次分次容积旋转调强放疗前基于骨骼的锥形束CT校准和基于软组织的三维超声校准。以锥形束CT校准数据为金标准, 采用Bland-Altman法分析三维超声校准数据与其一致性。准确度允许阈值设置为3 mm, 评价三维超声相对锥形束CT校准的准确度。采用logistic回归分析影响三维超声校准准确度的危险因素。结果共获取51例患者左右、头脚、腹背3个方向上765对锥形束CT和三维超声校准数据。左右方向上三维超声校准数据和锥形束CT校准数据分别为(1.39±0.11)和(1.13±0.07)mm, 头脚方向上分别为(1.98±0.20)和(1.61±0.12)mm, 腹背方向上分别为(2.68±0.48)和(1.78±0.27)mm, 差异均具有统计学意义(t=-6.42, P<0.001;t=-7.07, P<0.001;t=-7.34, P<0.0...     

鼻咽内超声实时引导经鼻咽针吸活检术对鼻咽部非腔内型病变诊断的围手术期管理

目的：探讨经鼻咽内超声实时引导鼻咽针吸活检术（endonasopharyngeal ultrasound-guided transnasopharyngeal needle aspiration,ENUS-TNNA）对鼻咽部非腔内型病变诊断的围手术期管理方法,以期保障ENUS-TNNA穿刺术的安全性及减少并发症的发生。方法：回顾性分析2016年8月至2022年5月四川省肿瘤医院采用ENUS-TNNA技术诊断的62例鼻咽部非腔内型病变患者的围手术期系统化管理方法及一般内镜资料。结果：经围手术期标准化及系统化管理,全组62例患者均一次性穿刺成功,获得了足够的组织标本。穿刺过程术中、后无大出血及其它严重并发症发生。ENUS-TNNA诊断鼻咽部非腔内型病变的敏感度、特异度及准确性分别为82.35%、100.00%和85.48%。结论：ENUS-TNNA是诊断鼻咽部非腔内型病变的安全及有效方法,良好的围手术期内镜管理方法可以保障ENUS-TNNA穿刺术的安全及减少并发症。     

Evaluation of intrafraction prostate motion tracking using the Clarity Autoscan system for safety margin validation

BackgroundThe purpose of the study was to monitor intrafraction prostate motion in real-time using transperineal 4D ultrasound (TPUS) and analyze trajectories to validate clinical safety margins.Methods401 trajectories of US monitoring sessions were retrospectively evaluated for 14 patients treated for prostate cancer. The Elekta Clarity Autoscan system was used for intrafraction monitoring along the 3 directions: superior-inferior (SI), left-right (LR) and anterior-posterior (AP).ResultsThe intrafraction monitoring resulted in a mean prostate displacement of (-0.06 ± 0.49) mm, (-0.09 ± 0.61) mm and (-0.01 ± 0.78) mm in the SI, LR and AP directions, respectively. Even though large deviations up to 8 mm were detected, the frequency of occurrence was less than 0.1%. The prostate moved within ±2 mm in 99%, 98.1%, and 96.6% of the treatment time in the SI, LR and AP directions, respectively. During 100 s of monitoring, the median displacement increased from 0.2 mm to 0.8 mm and the maximum displacements increased from 5.2 mm to 7.8 mm. The majority of displacement values (99%) were within the clinical safety margins which ensures a good target coverage.ConclusionsThe largest variation of intrafraction prostate displacement was observed along the AP direction. Throughout most of the treatment time, the prostate moved within a few millimeters. The extent of prostate displacement increased for longer monitoring times. During most of the tracking time, the prostate position was within the clinically safety margins.     

Planning target margin calculations for prostate radiotherapy based on intrafraction and interfraction motion using four localization methods

PURPOSE: To determine planning target volume (PTV) margins for prostate radiotherapy based on the internal margin (IM) (intrafractional motion) and the setup margin (SM) (interfractional motion) for four daily localization methods: skin marks (tattoo), pelvic bony anatomy (bone), intraprostatic gold seeds using a 5-mm action threshold, and using no threshold. METHODS AND MATERIALS: Forty prostate cancer patients were treated with external radiotherapy according to an online localization protocol using four intraprostatic gold seeds and electronic portal images (EPIs). Daily localization and treatment EPIs were obtained. These data allowed inter- and intrafractional analysis of prostate motion. The SM for the four daily localization methods and the IM were determined. RESULTS: A total of 1532 fractions were analyzed. Tattoo localization requires a SM of 6.8 mm left-right (LR), 7.2 mm inferior-superior (IS), and 9.8 mm anterior-posterior (AP). Bone localization requires 3.1, 8.9, and 10.7 mm, respectively. The 5-mm threshold localization requires 4.0, 3.9, and 3.7 mm. No threshold localization requires 3.4, 3.2, and 3.2 mm. The intrafractional prostate motion requires an IM of 2.4 mm LR, 3.4 mm IS and AP. The PTV margin using the 5-mm threshold, including interobserver uncertainty, IM, and SM, is 4.8 mm LR, 5.4 mm IS, and 5.2 mm AP. CONCLUSIONS: Localization based on EPI with implanted gold seeds allows a large PTV margin reduction when compared with tattoo localization. Except for the LR direction, bony anatomy localization does not decrease the margins compared with tattoo localization. Intrafractional prostate motion is a limiting factor on margin reduction.     

An evaluation of intrafraction motion of the prostate in the prone and supine positions using electromagnetic tracking

Purpose

To evaluate differences in target motion during prostate irradiation in the prone versus supine position using electromagnetic tracking to measure prostate mobility.

Materials/methods

Twenty patients received prostate radiotherapy in the supine position utilizing the Calypso Localization System® for prostate positioning and monitoring. For each patient, 10 treatment fractions were followed by a session in which the patient was repositioned prone, and prostate mobility was tracked. The fraction of time that the prostate was displaced by >3, 5, 7, and 10 mm was calculated for each patient, for both positions (400 tracking sessions).

Results

Clear patterns of respiratory motion were seen in the prone tracks due to the influence of increased abdominal motion. Averaged over all patients, the prostate was displaced >3 and 5 mm for 37.8% and 10.1% of the total tracking time in the prone position, respectively. In the supine position, the prostate was displaced >3 and 5 mm for 12.6% and 2.9%, respectively. With both patient setups, inferior and posterior drifts of the prostate position were observed. Averaged over all prone tracking sessions, the prostate was displaced >3 mm in the posterior and inferior directions for 11.7% and 9.5% of the total time, respectively.

Conclusions

With real-time tracking of the prostate, it is possible to study the effects of different setup positions on the prostate mobility. The percentage of time the prostate moved >3 and 5 mm was increased by a factor of three in the prone versus supine position. For larger displacements (>7 mm) no difference in prostate mobility was observed between prone and supine positions. To reduce rectal toxicity, radiotherapy in the prone position may be a suitable alternative provided respiratory motion is accounted for during treatment. Acute and late toxicity results remain to be evaluated for both patient positions.     

经直肠超声引导下前列腺穿刺活检术的研究进展

前列腺癌是西方发达国家最常见的恶性肿瘤之一.近年来,我国前列腺癌的发病率呈明显上升趋势。经直肠超声(transrectal ultrasound,TRUS)引导下的前列腺穿刺活检术是目前确诊前列腺癌的主要手段。本文就穿刺针数、前列腺体积、穿刺部位、前列腺高级别上皮内瘤变(high-grade prostaticintraepithelial neoplasia,HGPIN)、前列腺不典型小腺泡增生(atypical small acinar proliferation ofprostate,ASAP)及前列腺癌基因3(prostate cancer gene 3,PCA3)等影响前列腺穿刺结果的因素作一综述。     

The effect of androgen deprivation on the early changes in prostate volume following transperineal ultrasound guided interstitial therapy for localized carcinoma of the prostate

Purpose: To determine the change in volume of the prostate as a result of neoadjuvant androgen deprivation prior to prostate implant and in the early postimplant period following transperineal ultrasound guided palladium-103 brachytherapy for early-stage prostate cancer.

Methods and Materials: Sixty-nine men received 3 to 6 months of androgen deprivation therapy followed by treatment planning ultrasound followed 4 to 8 weeks later by palladium-103 implant of the prostate. All patients had clinical and radiographic stage T1c–T2b adenocarcinoma of the prostate. A second ultrasound study was carried out 11 to 13 days following the implant to determine the change in volume of the prostate as a result of the implant. The prehormonal and preimplant volumes were compared to the postimplant volume to determine the effect of hormones and brachytherapy on prostate volume.

Results: The median decrease in prostate volume as a result of androgen deprivation was 33% among the 54 patients with prostate volume determinations prior to hormonal therapy. The reduction in volume was greatest in the quartile of men with the largest initial gland volume (59%) and least in the quartile of men with smallest glands (10%). The median reduction in prostate volume between the treatment planning ultrasound and the follow-up study after implant was 3%, but 23 (33%) patients had an increase in prostate volume, including 16 (23%) who had an increase in volume >20%; 11 of these patients (16%) had an increase in volume >30%. The time course of development and resolution of this edema is not known. The severity of the edema was not related to initial or preimplant prostate volume or duration of hormonal therapy.

Conclusions: Prostate edema may significantly affect the dose delivered to the prostate following transperineal ultrasound guided brachytherapy. The effect on the actual delivered dose will be greater when shorter lived isotopes are used. It remains to be observed whether this edema will affect outcome.     

三维适形放疗联合高强度聚焦超声治疗老年性前列腺癌临床疗效观察

背景与目的:我国前列腺癌发病率呈逐年上升趋势,己成为老年男性常见的恶性肿瘤之一.本文旨在探讨三维适形放疗(three dimensionl conformal radiotherapy,3D-CRT)联合高强度聚焦超声(high intensity focused ultrasound,HIFU)治疗老年性前列腺癌的临床疗效及耐受性.方法:选择2004年1月-2009年12月,本院确诊为前列腺肿瘤的患者95例,48例采用3D-CRT联合HIFU治疗(3D-CRT+HIFU组),放射总剂量为TD 60 Gy/30 Fx,配合HIFU治疗5次:47例单纯采用3D-CRT治疗(3D-CRT组),放射剂量为TD(66^72)Gy/(33～36) Fx.分析两组患者局部控制率及无远处转移率:观察两组患者治疗前后血PSA、fPSA、T淋巴细胞亚群、NK细胞变化及正常组织的急性不良反应.结果:3DCRT+HIFU组治疗后CR+PR 45例(94%),3DCRT组CR十PR 36例(77%),差异有统计学意义(P<0.05):两组患者治疗前后血PSA及fPSA变化差异有统计学意义(P<0.05); 3D-CRT+HIFU组治疗后CD3+、CD4+、CD8+、CD4+/CD8+NK细胞均升高,治疗前后差异有显著统计学意义(P0.05);3D-CRT十HIFU组血细胞减少、反射性直肠炎和膀胱炎等II级以上急性不良反应较3D-CRT组减少,差异有显著统计学意义(P<0.01),但泌尿生殖道II级以上急性不良反应较3D-CRT组增加,差异有统计学意义(P<0.05).结论:3D-CRT联合H工FU治疗老年性前列腺癌,能提高肿瘤局部控制率,升高患者机体免疫细胞,并显著减少急性不良反应,是治疗失去手术指征的老年性前列腺癌的有效方法.     

An assessment of PTV margin definitions for patients undergoing conformal 3D external beam radiation therapy for prostate cancer based on an analysis of 10,327 pretreatment daily ultrasound localizations

INTRODUCTION: We have assessed the planning target volume (PTV) margins required for adequate treatment of the prostate in the absence of daily localization imaging based on the statistical analysis of a large data set obtained from 5 years of use of a two-dimensional ultrasound pretreatment localization device. METHODS AND MATERIALS: Data from 387 prostate patients were analyzed retrospectively. Every patient in the study received daily pretreatment localization resulting in a total of 10,327 localizations, each comprising an isocenter displacement in three directions: anteroposterior, right-left lateral, and superior-inferior. The mean displacement for each direction for each patient was computed from daily treatment records, and a mean of the means was used in the analysis. RESULTS: The mean displacements required to shift the target to the required position were 6.1 mm posterior (4.4 mm SD), 2.1 mm superior (4.5 mm SD), and 0.5 mm right (3.6 mm SD). The 6.1-mm shift posterior is indicative of a systematic uncertainty. Differences in planning conditions between the computed tomography simulation and the treatment room may account for this discrepancy. CONCLUSION: Our study has revealed systematic intertreatment uncertainties that would have required a nonuniform PTV margin ranging in dimensions between 2.7 mm anterior, 14.9 mm posterior, 7.7 mm right, 6.7 mm left, 11 mm superior, and 7 mm inferior to encompass the prostate for 95% of our sample if the ultrasound localization system were not used. In the absence of systematic uncertainties, a uniform PTV margin of 9 mm would suffice.