巨块型NSCLC质子部分立体定向消融推量放疗的剂量学优势

目的 探索肿瘤长径>8 cm的巨块非小细胞肺癌（NSCLC）放疗中质子部分立体定向消融推量放疗（P‐SABR）的剂量学优势。方法 收集既往应用光子P‐SABR治疗的9例巨块NSCLC的定位影像。在光子肿瘤推量靶区（光子GTVb）基础上逐步外扩,直到重要危及器官受量达3.0 Gy/次时停止,形成质子肿瘤推量靶区（质子GTVb）,质子GTV、CTV范围同光子,分别制订光子固定野调强放疗（光子FF‐IMRT）、光子容积调强弧形治疗（光子VMAT）、质子调强放疗（IMPT）计划。对比不同治疗技术的剂量学参数。结果 光子GTVb和质子GTVb占GTV体积比分别为25.4%±13.4%和69.7%±30.0%（P<0.001）。光子IMRT、光子VMAT、IMPT的CTV平均剂量分别为（76.1±4.9）Gy、（78.2±3.6）Gy、（84.7±4.9）Gy,生物有效剂量（BED）≥90 Gy所包含肿瘤占GTV体积的百分比分别为70.7%±21.7%、76.8%±22.1%、97.9%±4.0%,质子较光子P‐SABR计划显著提高了靶区剂量及BED（P<0.05）。质子较光子计划还降低了危及器官受量,其中光子FF‐IMRT、光子VMAT和IMPT的双肺V_{5 Gy}分别为49.2%±22.0%、56.8%±19.0%和16.1%±6.3%（P<0.001）。结论 质子P‐SABR较光子可在降低危及器官受量情况下,扩大肿瘤推量靶区范围并提高肿瘤内BED,有望进一步提高巨块NSCLC的局部控制率。     

巨块型NSCLC质子部分立体定向消融推量放疗的剂量学优势

目的 探索肿瘤长径>8 cm的巨块非小细胞肺癌（NSCLC）放疗中质子部分立体定向消融推量放疗（P‐SABR）的剂量学优势。方法 收集既往应用光子P‐SABR治疗的9例巨块NSCLC的定位影像。在光子肿瘤推量靶区（光子GTVb）基础上逐步外扩,直到重要危及器官受量达3.0 Gy/次时停止,形成质子肿瘤推量靶区（质子GTVb）,质子GTV、CTV范围同光子,分别制订光子固定野调强放疗（光子FF‐IMRT）、光子容积调强弧形治疗（光子VMAT）、质子调强放疗（IMPT）计划。对比不同治疗技术的剂量学参数。结果 光子GTVb和质子GTVb占GTV体积比分别为25.4%±13.4%和69.7%±30.0%（P<0.001）。光子IMRT、光子VMAT、IMPT的CTV平均剂量分别为（76.1±4.9）Gy、（78.2±3.6）Gy、（84.7±4.9）Gy,生物有效剂量（BED）≥90 Gy所包含肿瘤占GTV体积的百分比分别为70.7%±21.7%、76.8%±22.1%、97.9%±4.0%,质子较光子P‐SABR计划显著提高了靶区剂量及BED（P<0.05）。质子较光子计划还降低了危及器官受量,其中光子FF‐IMRT、光子VMAT和IMPT的双肺V_{5 Gy}分别为49.2%±22.0%、56.8%±19.0%和16.1%±6.3%（P<0.001）。结论 质子P‐SABR较光子可在降低危及器官受量情况下,扩大肿瘤推量靶区范围并提高肿瘤内BED,有望进一步提高巨块NSCLC的局部控制率。     

Intensity-modulated proton therapy versus helical tomotherapy in nasopharynx cancer: planning comparison and NTCP evaluation

PURPOSE: To compare intensity-modulated proton therapy (IMPT) and helical tomotherapy (HT) treatment plans for nasopharynx cancer using a simultaneous integrated boost approach. METHODS AND MATERIALS: The data from 6 patients who had previously been treated with HT were used. A three-beam IMPT technique was optimized in the Hyperion treatment planning system, simulating a "beam scanning" technique. HT was planned using the tomotherapy treatment planning system. Both techniques were optimized to simultaneously deliver 66 Gy in 30 fractions to planning target volume (PTV1; GTV and enlarged nodes) and 54 Gy to PTV2 subclinical, electively treated nodes. Normal tissue complication probability calculation was performed for the parotids and larynx. RESULTS: Very similar PTVs coverage and homogeneity of the target dose distribution for IMPT and HT were found. The conformity index was significantly lower for protons than for photons (1.19 vs. 1.42, respectively). The mean dose to the ipsilateral and contralateral parotid glands decreased by 6.4 Gy and 5.6 Gy, respectively, with IMPT. The volume of mucosa and esophagus receiving >/=20 Gy and >/=30 Gy with IMPT was significantly lower than with HT. The average volume of larynx receiving >/=50 Gy was significantly lower with HT, while for thyroid, it was comparable. The volume receiving >/=30, >/=20, and >/=10 Gy in total body volume decreased with IMPT by 14.5%, 19.4%, and 23.1%, respectively. The normal tissue complication probability for the parotid glands was significantly lower with IMPT for all sets of parameters; however, we also estimated an almost full recovery of the contralateral parotid with HT. The normal tissue complication probability for the larynx was not significantly different between the two irradiation techniques. CONCLUSION: Excellent target coverage, homogeneity within the PTVs, and sparing of the organs at risk were reached with both modalities. IMPT allows for better sparing of most organs at risk at medium-to-low doses.     

初治鼻咽癌调强放疗布野及联合化疗的临床研究

[目的]研究鼻咽癌调强放射治疗(IMRT)的投照方式、近期临床疗效,以及单纯放疗和放、化疗结合的耐受性。[方法]2003年12月￣2005年12月157例初治鼻咽癌患者鼻咽和全颈及锁骨上全程实施前7野IMRT。鼻咽大体肿瘤体积(GTV1)、颈部大体肿瘤体积(GTV2)、临床靶体积1(CTV1)和临床靶体积2(CTV2)处方剂量分别为70Gy、66Gy、60Gy、50Gy,共32分次。88例患者行联合化疗。采用Kaplan-Meier法进行生存分析,RTOG标准评价急性反应和晚期损伤。[结果]治疗计划结果显示,靶区内GTV1、GTV2、CTV1和CTV2的平均剂量分别为70.5Gy、67.0Gy、60.1Gy和51.2Gy。中位随访时间16个月,1、2年局部区域无进展和无远处转移生存率及总生存率分别为97.4%、94.9%和93.6%、89.4%及96.4%、92.7%。放化综合治疗组的口咽、黏膜反应及血液系统毒性明显高于单纯放疗组。患者近期毒副反应均可以耐受,口干症状随着治疗后时间的延长逐渐减轻。[结论]IMRT使靶体积照射剂量提高,而周围器官受照剂量降低,对初治鼻咽癌可获得理想的局部区域控制,放化综合治疗对控制远处转移有一定价值。     

鼻咽癌调强放射治疗的剂量学特点

[目的]分析鼻咽癌调强放疗各个靶区和周围正常器官的剂量学特点.[方法]2004年7月至10月入院的10例初治鼻咽癌调强放疗病人,用前7野方案,每野的照射范围从颅底到锁骨上淋巴预防区.剂量处方是:GTV1为2.18Gy/次,32次,GTV2为2.03Gy/次,32次,CTV1为1.88Gy/次,32次,CTV2为1.80Gy/次,28次.研究GTV的最大、最小和平均剂量,CTV的最小剂量,脊髓、脑干和晶状体的最大剂量,腮腺的50%体积受照剂量.[结果]10例病人GTV1的最大、最小和平均剂量(均值)分别是72.01Gy、68.65Gy、70.48Gy,GTV2的最大、最小和平均剂量(均值)分别是68.66y、65.50Gy、66.98Gy,CTV1的最小剂量为60.10Gy,CTV2的最小剂量为51.18Gy,脊髓、脑干和晶体状的最大剂量分别为44.7Gy、51.7Gy和6.8Gy,高剂量侧和低剂量侧,腮腺的50%体积的受照剂量分别为44.39Gy和39.36Gy.[结论]调强放疗可以使各个靶区得到足够的、均匀的剂量分布,周围的正常组织受到比较好的保护,腮腺50%体积受照剂量控制在40Gy～45Gy,显示已有较好的保护作用.     

复发鼻咽癌调强放疗的剂量学探讨

目的：分析和评价复发鼻咽癌调强放疗（IMRT）的剂量学特点。方法：30例局部、区域复发的鼻咽癌患者使用IMRT的再程放疗,其中7例同时伴有颈淋巴结转移。根据1992年福州分期标准进行再分期,I、Ⅱ、Ⅲ、Ⅳ期分别为7、7、4、12例。鼻咽大体肿瘤体积（GTV）处方剂量为58．80—78．76Gy,分次剂量2．0—2．92Gy。结果：治疗计划GTV的中位体积为37．46cm。（14．30—227．52cm。）,覆盖鼻咽GTVD。;的平均剂量为62．56Gy,GTVV95的平均体积为98．69％;靶区内GTV、cTV,和CTV,的平均剂量分别为65．82Gy、54．02Gy和50．20Gy;GTV的平均分割剂量为2．28Gy（2．0—2．92Gy）。结论：IMRT能较好覆盖肿瘤靶区而降低邻近敏感器官剂量。     

图像引导对宫颈癌治疗的作用

目的:分析宫颈癌根治性图像引导放疗(IGRT)对靶区剂量的影响,探讨其合理应用模式。方法:选取2012—2016年于中国人民解放军总医院第七医学中心行螺旋断层放疗(HT)的20例宫颈癌患者,应用兆伏级CT(MVCT)图像在HT自适应模块上进行重建及模拟,分别得到有/无图像引导下的受照剂量参数;将各单次剂量分布和对应的融...     

Helical tomotherapy and intensity modulated proton therapy in the treatment of early stage prostate cancer: A treatment planning comparison

Purpose

To compare helical tomotherapy (HT) and intensity modulated proton therapy (IMPT) on early stage prostate cancer treatments delivered with simultaneous integrated boost (SIB) in moderate hypofractionation.

Material/methods

Eight patients treated with HT were replanned with two-field IMPT (2fIMPT) and five-field IMPT (5fIMPT), using a small pencil beam size (3 mm sigma). The prescribed dose was 74.3 Gy in 28 fractions on PTV1 (prostate) and PTV2 (proximal seminal vesicles), 65.5 Gy on PTV3 (distal seminal vesicles) and on the overlap between rectum and PTVs.

Results

IMPT and HT achieved similar target coverage and dose homogeneity, with 5fIMPT providing the best results. The conformity indexes of IMPT were significantly lower for PTV1+2 and PTV3. Above 65 Gy, HT and IMPT were equivalent in the rectum, while IMPT spared the bladder and the penile bulb from 0 to 70 Gy. From 0 up to 60 Gy, IMPT dosimetric values were (much) lower for all OARs except the femur heads, where HT was better than 2fIMPT in the 25-35 Gy dose range. OARs mean doses were typically reduced by 30-50% by IMPT. NTCPs for the rectum were within 1% between the two techniques, except when the endpoint was stool frequency, where IMPT showed a small (though statistically significant) benefit.

Conclusions

HT and IMPT produce similar dose distributions in the target volume. The current knowledge on dose-effect relations does not allow to quantify the clinical impact of the large sparing of IMPT at medium-to-low doses.     

Anti‐epidermal growth factor receptor therapy concurrently with induction chemotherapy in locoregionally advanced nasopharyngeal carcinoma

Little is known about the efficacy and toxicity of anti‐epidermal growth factor receptor therapy concurrently with induction chemotherapy (IC) in locoregionally advanced nasopharyngeal carcinoma (LA‐NPC). The present study aimed to address this question. We identified 2848 patients with newly diagnosed LA‐NPC receiving IC between January 2012 and May 2015. The propensity score matching (PSM) method was used to balance various factors and to match patients. Survival outcomes and toxicities between different groups were compared. In total, 596 patients were selected at a 1:3 ratio, with 149 in the IC + CTX/NTZ group and 447 in the IC alone group. The 3‐year disease‐free survival, overall survival, distant metastasis‐free survival and locoregional relapse‐free survival rates for IC + CTX/NTZ vs IC alone were 84.3% vs 75.2% (P = .059), 94.0% vs 87.9% (P = .053), 88.0% vs 84.9% (P = .412) and 93.3% vs 88.2% (P = .242). Multivariate analysis established a treatment group (IC vs IC + CTX/NTZ) as a prognostic predictor for DFS (hazard ratio [HR], 1.497; 95% confidence interval [CI], 1.016‐2.206; P = .041) and OS (HR, 1.984; 95%, CI, 1.023‐3.848; P = .043). Grade 3‐4 skin reaction (15.4% vs 0.4%, P < .001) and mucositis (10.1% vs 2.7%, P < .001) were more common in the IC + CTX/NTZ group than that in the IC alone group. Our findings suggested that CTX/NTZ in combination with IC may be a more effective and promising strategy for patients with LA‐NPC treated with intensity‐modulated radiotherapy.     

Prediction of Acute Toxicity Grade ≥ 3 in Patients With Locally Advanced Non–Small-Cell Lung Cancer Receiving Intensity Modulated Radiotherapy and Concurrent Low-Dose Cisplatin

BackgroundIntensity modulated radiotherapy (IMRT) is increasingly used with concurrent chemotherapy but toxicity data are not well investigated. We correlated clinical and dosimetric parameters with acute toxicity grade ≥ 3 in patients with locally advanced NSCLC treated with IMRT and concurrent low-dose cisplatin.Patients and MethodsWe analyzed age, PS, comorbidities, gross tumor volume, and the volume of the esophagus irradiated with 50 Gy (V50oes) in relation with acute toxicity. The mean lung dose (MLD) and pulmonary toxicity was described. Treatment consisted of 24 × 2, 75 Gy, and daily cisplatin 6 mg/m². Patients with an MLD ≥ 20 Gy or a PS > 2 were excluded from CCRT. Toxicity was prospectively scored using the Common Toxicity Criteria for adverse events version 3.0. The Charlson Comorbidity Index (CCI) was applied for scoring comorbidities. Multivariable logistic regressions for toxicity and survival estimates (Kaplan-Meier) were used for evaluation.ResultsFrom 2008 to 2011, 188 patients received standard CCRT. In 35% of the patients, acute toxicity grade ≥ 3 was reported. Grade 5 toxicity was scored in 1% of the patients. V50oes (odds ratio [OR], 1.33 per 10% increase; P = .01) and PS ≥ 2 (OR, 3.45; P = .07) were significantly correlated with acute toxicity ≥ grade 3. No differences in toxicity were observed between age groups (< 70 and ≥ 70; P = .26), and those with a CCI score < 5 and ≥ 5, and acute severe toxicity (P = .36). Grade ≥ 3 pulmonary toxicity was seen in 7%. The 1- and 2-year overall survival in stage III disease were 78% and 52%, respectively. Patients with a poor PS or a high CCI score had similar survival outcomes.ConclusionConcurrent low-dose cisplatin using IMRT is effective in a large cohort of consecutive patients with NSCLC and life threatening toxicity is rare (1%). PS ≥ 2 and V50oes are correlated with acute toxicity grade ≥ 3.     

诱导化疗后局部晚期鼻咽癌调强放疗肿瘤靶区勾画方式改变对剂量分布和临床疗效的影响

背景与目的：晚期鼻咽癌诱导化疗后大体肿瘤体积（gross tumor volume,GTV）明显缩小。本研究探讨按化疗后肿瘤改变GTV勾画方式对靶区和正常组织剂量以及临床疗效的影响。方法：从2008年1月至2009年4月收治24例局部晚期鼻咽癌初治患者,采用TPF诱导化疗加同期调强放化疗方案进行治疗。调强放疗原发灶GTV分为诱导化疗后可见的肿瘤和诱导化疗后肿瘤消退区域两部分。选取10例患者,比较按诱导化疗前后肿瘤勾画GTV所做计划的剂量分布．同时观察全组患者毒副反应和近期疗效。结果：诱导化疗后和前原发灶GTV平均体积分别为25．5cm^3和51．1cm^3（P=0．001）;颈淋巴结GTV9．1cm^3和31．4cm^3（P=0．035）;原发灶＋颈淋巴结GTV33．2cm^3和82．6cm^3（P=0．004）,诱导化疗使肿瘤总体积减少了61％,64．6Gy等剂量线所包括的体积分别为422．9cm^3和457．9cm^3（p=0．003）：68Gy等剂量线所包括的体积274．2cm^3和334．5cm^3（P=0．041）。诱导化疗后鼻咽病灶和颈部淋巴结完全缓解率达38％。同期放化疗结束后3个月鼻咽病灶和颈部淋巴结完全缓解率达100％。该模式同期放化疗毒性反应与单纯调强同期放化疗相似。经中位期9个月的随访．全组患者局部区域控制率为100％。仅1例患者在15个月出现多处远处转移。结论：鼻咽癌TPF方案诱导化疗后肿瘤体积明显缩小,按化疗后肿瘤勾画GTV的调强放疗能使高剂量区体积减少,同期放化疗毒性反应未见加重,并且具有较好的近期治疗效果。     

鼻咽癌小靶区调强放疗及化疗的远期疗效分析

目的 分析鼻咽癌(NPC)缩小临床靶区调强放疗(IMRT)的长期疗效,为小靶区IMRT技术在NPC中应用提供依据。方法 2003-2007年接受IMRT的鼻咽癌患者413例,中位年龄45岁,男311例、女102例。按第6版AJCC分期标准Ⅰ期3例、Ⅱ期66例、Ⅲ期235例、Ⅳ_a期78例、Ⅳ_b期31例。336例患者接受了以铂类为基础的化疗。结果 随访率100%,5年总生存率、局部控制率、无区域复发生存率、无远处转移生存率和无瘤生存率分别为80%、93%、96%、81%和75%。多因素分析提示T分期、N分期、年龄是影响总生存的预后因素(P=0.001、0.001、0.002),T分期、N分期是无远处转移生存的预后因素(P=0.000、0.001)。进展期鼻咽癌患者中诱导化疗组5年总生存有高于无诱导化疗组趋势(78%∶68%,P=0.053),辅助化疗者5年无远处转移生存率低于无辅助化疗者(65%∶83%,P=0.003)。结论 鼻咽癌小靶区IMRT技术安全可靠,远期疗效理想。     

Serious complications of pancreatoduodenectomy correlate with lower rates of adjuvant chemotherapy: Would high-risk patients benefit from neoadjuvant therapy?

IntroductionPatients who suffer a serious complication of pancreatoduodenectomy (PD) may have their adjuvant chemotherapy (AC) delayed or omitted as a result. We aimed to investigate whether PD complications affected AC rates.Materials and methodsA retrospective analysis of all PD patients with histologically-confirmed pancreatic ductal adenocarcinoma (2006–2015) was performed; 90-day mortality patients were excluded. Patients who commenced AC were compared to those who did not (morbidity rates and survival) and patients who developed selected postoperative complications were compared to those who did not (AC rates and survival).Results157 patients were included and 90-day mortality was 3.8%. Of the remaining patients, 102 (68.5%) received AC (AC data unavailable for two patients). Survival was longer in the AC group (p = 0.004). AC patients had less frequently experienced a postoperative chest infection (8.82% vs 34.0%, p = 0.0003) or a postoperative complication which was Clavien-Dindo (CD) grade ≥ II (29.4% vs 57.4%, p = 0.0019) or ≥ III (6.86% vs 21.3%, p = 0.023). Patients who experienced a postoperative chest infection (36.0% vs 75.0%, p = 0.0003) or a postoperative complication which was CD grade ≥ II (48.9% vs 73.1%, p = 0.0099) or ≥ III (29.4% vs 70.3%, p = 0.0018) less frequently commenced AC.ConclusionPatients who received AC had less frequently experienced a serious postoperative complication. Efforts should be made to preoperatively identify those who are high-risk for a serious complication as this cohort may benefit from neoadjuvant therapy.     

三维治疗计划系统对胸部食管癌常规放疗计划肿瘤剂量的评估

目的 用三维治疗计划系统评估胸部食管癌传统三野放疗计划的肿瘤剂量分布。方法 19例确诊为食管癌的患者均予胸部CT扫描，在CT上勾画GTV，CTV，PTV，然后用Cad Plan 64．7三维治疗计划系统产生传统三野等中心虚拟治疗计划，通过DVH比较GTV，CTV，PTV所受剂量，靶区适形度及靶区剂量均匀度。结果GTV，CTV，PTV最大剂量分别为：51．64，51．94，51．48Gy；最小剂量分别为：41．17，2531，1894Gy；平均剂量分别为：495，47．34，42．92Gy；适形指数分别为：0.94，0.69，0.38；剂量变异度分别为：2．2，7．57，14.56Gy。结论 传统的食管癌设野定位方法不能满足放射治疗的临床剂量学要求，应采用CT定位，通过三维计划系统的方法来确定食管癌的照射方法。     

鼻咽癌缩小临床靶体积调强放疗疗效探讨

目的 探讨鼻咽癌(NPC)缩小临床靶体积(CTV)调强放疗(IMRT)的疗效及毒副反应.方法 2003年8月到2007年3月共380例NPC患者入组研究,其中AJCC分期Ⅰ期1例、Ⅱ期71例、Ⅲ期197例、Ⅳ期111例.高危临床靶体积(CTV1)包括肿瘤靶体积(GTV)及整个鼻咽黏膜,低危临床靶体积(CTV2)包括整个鼻咽腔(包括鼻腔后部5 mm)、上颌窦(后壁前5 mm)、翼腭窝、后组筛窦、咽旁间隙、颅底、斜坡及颈椎前1/3、咽后淋巴引流区(内侧组从颅底至第2颈椎上缘).处方剂量GTV 66.00～69.75 Gy,CTV160.00～66.65 Gy,CTV2或CTVN54.0～55.8 Gy,分割次数均为30～33次.其中308例局部进展患者接受了以铂类为基础的诱导化疗.结果 随访率为100%,随访满3年者145例.3年局部控制率、区域控制率、无远处转移生存率、无瘤生存率及总生存率分别为94.9%、97.4%、86.2%、80.9%和89.0%.多因素分析表明N分期是影响无远处转移生存率(x2=20.80,P=0.001)的预后因素,N分期(x2=18.30,P=0.003)及年龄(x2=7.31,P=0.004)是影响总生存率的独立预后因素.5.6%患者放疗后2年仍存在2级口干,未观察到4级远期副反应.4.2%、2.6%和12.1%患者分别出现局部、区域复发及远处转移.结论 采用缩小CTV2IMRT方法治疗NPC可获得较好的局部区域控制率及总生存率,急慢性副反应可接受.     

Update report of nasopharyngeal carcinoma treated with reduced-volume intensity-modulated radiation therapy and hypothesis of the optimal margin

Background and purpose

To establish the minimally required margins in different directions measured from GTV in the definitive treatment of nasopharyngeal carcinoma (NPC) using IMRT based on the 5-year results.

Methods and materials

Between November 2003 and May 2007, 414 patients with non-metastatic NPC were treated with IMRT according to our institutional protocol. Treatment outcomes at 5 years were analyzed. Distances from GTV-T to CTV2 (i.e., CTV 59.4 Gy) in 6 directions (anterior, posterior, superior, inferior, and bilateral) were measured and analyzed.

Results

The 5-year estimated overall survival (OS), disease free survival (DFS), local control (LC) were 80%, 77% and 95%, respectively. For the margins measured from GTV-T to CTV2, margins used with T4 disease were significantly and uniformly smaller than the whole group in all the 6 directions (P = 0.000, 0.000, 0.000, 0.000 and 0.046, respectively). However, no increase of local recurrence was associated to this limited margins used.

Conclusions

Our 5-years’ experience showed a very high LC rate. The strategy we used for CTV delineation was safe and reliable. Determined CTV through GTV expansion to a minimally required margin, using GTV + margin (used in our T4 patients) + the whole nasopharyngeal mucosa, especially for the patients with early T disease, might be feasible.     

Patterns of failure after stereotactic radiotherapy of intracranial meningioma

The aim of this work is to evaluate patterns of failure in patients with recurrent meningioma after stereotactic radiotherapy. Of 411 patients with intracranial meningioma treated with radiotherapy at our institution, 22 patients with local tumor progression diagnosed by magnetic resonance imaging (MRI) after radiotherapy (RT) were identified and further investigated. The histologic grade of the meningiomas was World Health Organization (WHO) grade I in 54.5%, WHO grade II in 27.3%, and WHO grade III in 9.1% of cases. Fourteen patients had received fractionated stereotactic RT; five patients underwent intensity-modulated RT. The median total dose was 57.6 Gy at 1.8 Gy/fraction, five times weekly. Local recurrences were divided into the dosimetric categories “central” (“in-field”) and “marginal” (“out-field”). Median follow-up was 59.5 months. Eleven local failures were found to be central, and 11 were marginal. Recurrence-free survival (P < 0.05) and site of local recurrence (P < 0.05) depended statistically significantly on histology. Median recurrence-free survival was 46 months for patients with benign meningioma (WHO grade I) and 31.5 months for patients with higher-grade meningioma (WHO grade II/III). In the WHO grade I group, three recurrences were central and nine were marginal, whereas in the WHO grade II/III group seven recurrences were central and one was marginal. Median time to local tumor progression and site of local recurrence significantly depended on histological grade of meningioma. Regarding site of failure, improvement of dose coverage for benign meningiomas and dose escalation for high-grade tumors might further improve therapy outcome.     

诱导化疗对鼻咽癌调强放疗靶区和剂量分布的影响研究

目的分析诱导化疗前后鼻咽癌肿瘤体积的变化,及靶区和正常组织剂量分布的变化。方法自2009年3月至2010年8月收治12例经病理证实的初治局部晚期鼻咽癌患者,调强放疗前接受PF方案诱导化疗2周期。对患者诱导化疗前作CT模拟定位扫描后行靶区勾画和制定诱导化疗前调强放疗(IMRT)计划。2周期诱导化疗后进行第2次CT扫描,并将两次CT图像进行融合后测量肿瘤体积和制定诱导化疗后IMRT计划。采用配对t检验分析诱导化疗前后扫描肿瘤体积的变化,及靶区和正常组织剂量分布的变化。结果诱导化疗前和后原发灶GTVnx平均体积分别为(39.75±19.17)cm3和(25.65±15.11)cm3(t=4.203,P=0.001);颈淋巴结GTVnd(33.78±28.9)cm3和(15.56±14.91)cm3(z=2.94,P=0.003);原发灶+颈淋巴结GTV(73.53±31.55)cm3和(41.2±24.06)cm3(t=4.753,P=0.001);诱导化疗使肿瘤总体积减少了52.9%。66.5 Gy等剂量线所包括的体积分别为(302.0±110.3)cm3和(248.4±79.0)cm3(P=0.023),63 Gy等剂量线所包括的体积分别为(413.2±117.4)cm3和(409.1±115.1)cm3(P=0.097)。诱导化疗使T和N分期降低达33.3%和50%。结论诱导化疗前后肿瘤体积变化较大,按化疗后肿瘤勾画GTV的调强放疗能使高剂量区体积减少。