质子碳离子治疗腺样囊性癌的近期疗效及不良反应

目的 观察束流调强粒子放射治疗头颈部腺样囊性癌的不良反应和近期疗效。方法 2015年5月至2016年3月,8例初治的病理证实的头颈部腺样囊性癌患者,5例患者为局部晚期（T_3-4期）,3例患者为R1切除,5例患者为活检术后或R2切除。7例患者采用束流调强质子放射治疗（IMPT）联合束流调强碳离子放射治疗（IMCT）,IMPT放射临床靶区体积（CTV）56 GyE/28次后,采用IMCT给予局部加量治疗15 GyE/5次。1例患者接受了单纯的IMPT治疗。结果 根据新版实体瘤疗效评价标准（RECIST）评估标准,本组5例具有明确肿瘤病灶的患者,在放疗结束时和结束后1个月,3例肿瘤部分缓解（PR）,2例疾病稳定（SD）;4例放疗结束后3个月随访时,有2例达到完全缓解（CR）,1例PR,1例SD。至2016年3月所有患者均无肿瘤进展和死亡。放疗期间,2例发生了3级口腔黏膜反应,随访3个月无重度皮肤反应发生。结论 束流调强粒子放射治疗头颈部腺样囊性癌安全、有效,但后期不良反应和远期疗效尚需更长时间的观察。     

基于元启发策略的肿瘤调强放疗自动计划方法

目的提出一种基于元启发策略的放疗自动计划方法(ATP-STAR),并验证其有效性。方法ATP-STAR方法的主要过程为先对优化参数进行向量化编码,采用高斯卷积修正优化参数,再利用模拟退火选择备选优化参数向量集,结合射野通量优化,并行探索最优的优化参数组合,实现计划自动试错。选取20例肿瘤个体化差异较大的病例进行方法测试。邀请具备5年以上临床工作经验的物理师进行人工计划设计。人工计划和ATP-STAR计划均基于开源matRad计划系统完成,射野及处方剂量与临床治疗计划保持一致。分析不同病种ATP-STAR与人工计划的靶区和危及器官剂量学差异。结果对靶区而言,ATP-STAR计划的均匀性优于人工计划(脑瘤:z=2.28,P=0.022;肺癌:z=2.29,P=0.022;肝癌:z=2.11,P=0.035),脑瘤和肝癌ATP-STAR计划的适形性与人工计划相当,肺癌ATP-STAR计划的适形性略差于人工计划(z=2.29,P=0.022)。对脑瘤的危及器官而言,相比于人工计划,ATP-STAR计划的左眼晶状体Dmean平均受量由2.19 Gy降至1.76 Gy(z=2.28,P=0.022),左视神经Dmean由11.36 Gy降至10.22 Gy(z=2.28,P=0.022),右视神经Dmax由32.92 Gy降至29.97 Gy(z=2.10,P=0.036),垂体Dmax由39.53 Gy降至35.21 Gy(z=2.29,P=0.022)。对肺癌的危及器官而言,ATP-STAR计划的脊髓Dmax平均受量由38 Gy降至31.17 Gy(z=2.12,P=0.034),双肺Dmean由8.51 Gy降至8.07 Gy(z=2.29,P=0.022),心脏Dmean由3.21 Gy降至2.69 Gy(z=2.29,P=0.022)。对肝癌的危及器官而言,ATP-STAR计划的脊髓Dmax由18.19 Gy降至14.76 Gy(z=2.11,P=0.035),肝脏Dmean由15.61 Gy降至14.45 Gy(z=2.11,P=0.035),肾脏Dmean由4.76 Gy降至4.04 Gy(z=2.10,P=0.036)。结论ATP-STAR方法较少依赖人工计划设计经验,易于推广,有望改善调强放疗计划质量及一致性,并节省临床人力和时间成本。     

Application of positron emission tomography/computed tomography in radiation treatment planning for head and neck cancers

18-fluorodeoxygluocose positron emission tomography/computed tomography (¹⁸FDG-PET/CT) provides significant information in multiple settings in the management of head and neck cancers (HNC). This article seeks to define the additional benefit of PET/CT as related to radiation treatment planning for squamous cell carcinomas (SCCs) of the head and neck through a review of relevant literature. By helping further define both primary and nodal volumes, radiation treatment planning can be improved using PET/CT. Special attention is paid to the independent benefit of PET/CT in targeting mucosal primaries as well as in detecting nodal metastases. The utility of PET/CT is also explored for treatment planning in the setting of SCC of unknown primary as PET/CT may help define a mucosal target volume by guiding biopsies for examination under anesthesia thus changing the treatment paradigm and limiting the extent of therapy. Implications of the use of PET/CT for proper target delineation in patients with artifact from dental procedures are discussed and the impact of dental artifact on CT-based PET attenuation correction is assessed. Finally, comment is made upon the role of PET/CT in the high-risk post-operative setting, particularly in the context of radiation dose escalation. Real case examples are used in these settings to elucidate the practical benefits of PET/CT as related to radiation treatment planning in HNCs.     

头颈部放疗后软组织损伤的CT表现

目的 :本文旨在观察和探讨头颈部肿瘤放疗后软组织损伤的CT表现 ,以提高对头颈部放射性损伤的影像学认识。方法 :对头颈部恶性肿瘤放疗后 70例作CT扫描观察 ,计 13 3次扫描 ,扫描 1次 3 8例 ,2次 15例 ,3次以上 17例。观察时间分为放疗后近期 ( 6个月以内 )、中期 ( 6～ 12个月 )和远期 ( 12个月以上 )。放疗剂量为 40～ 72Gy(单程放疗 )、14 0Gy(二程及二程以上放疗 )。全部病例均有放疗前CT图像对照。结果 :CT所见包括皮下脂肪层变薄 2 6例 ,皮肤增厚15例 ,皮肤凹陷 2 6例 ,肌肉萎缩 19例 ,颈深筋膜增厚 15例 ,皮下纤维性增生 18例 ,涎腺萎缩 19例 ,复发性肿瘤 18例。结论 :CT对头颈部软组织放射性损伤的表现和程度的判断是准确的 ,能为临床治疗提供参考依据     

双源CT扫描模式对头颈部辐射剂量和影像质量的影响

目的 探讨头颈部CT扫描中,不同扫描模式对辐射剂量和影像质量的影响程度。方法 利用头颈部仿真模体和双源CT,分别使用固定扫描条件120 kV和200 mAs,以及自动管电流调制技术（CARE Dose 4D）、自动管电压调制技术（CARE kV）和部分角度扫描模式（X-CARE）的组合进行成像,分别为120 kV+200 mAs、120 kV+200 mAs+X-CARE、CARE Dose 4D+120 kV、CARE Dose 4D+120 kV+X-CARE、CARE Dose 4D+CARE kV、CARE Dose 4D+CARE kV+X-CARE 6种扫描模式。每次扫描均使用两片热释光剂量片（TLD）分别测量眼晶状体和甲状腺的剂量,两片TLD所测数值取均值。记录以上各种扫描时的容积CT剂量指数（CTDI_vol）和剂量长度乘积（DLP）,测量眼晶状体层面和甲状腺层面影像的对比度噪声比（CNR）。结果 120 kV+200 mAs扫描时,眼晶状体和甲状腺的器官剂量分别为19.8和26.0 mGy,使用120 kV+200 mAs+X-CARE可降低剂量至13.3和22.2 mGy;与CARE Dose 4D+120 kV相比,CARE Dose 4D+CARE kV可使CTDI_vol由13.1降至10.1 mGy,眼晶状体剂量和甲状腺剂量由20.8和23.7 mGy分别降至16.6和19.9 mGy,而使用CARE Dose 4D+CARE kV+X-CARE时,器官剂量又进一步分别降至6.3和11.0 mGy,但影像质量显著降低;与CARE Dose 4D+120 kV相比,使用CARE Dose 4D+120 kV+X-CARE,眼晶状体和甲状腺剂量分别由20.8和23.7 mGy降至9.6和15.1 mGy,同时CTDI_vol由13.1 mGy降至9.3 mGy。使用CARE Dose 4D+CARE kV+X-CARE时,CTDI_vol和器官剂量降至最低,但头颅和颈部CNR也降至最低。结论 颅脑扫描时CARE Dose 4D+120 kV+X-CARE模式、颈部扫描时CARE Dose 4D+CARE kV模式在保持影像质量较好的同时可有效降低辐射剂量。当对影像质量要求不高时可选用CARE Dose 4D+CARE kV+X-CARE模式,从而显著降低辐射剂量。     

Interstitial brachytherapy in the management of persistent head and neck disease after definitive external beam radiation therapy

PurposePersistent disease after definitive external beam radiation therapy for head and neck (H&;N) malignancies negatively impacts survival. In this series, the effectiveness of low-dose-rate brachytherapy in the management of persistent H&;N disease is explored.MethodsAll patients who received brachytherapy for persistent H&;N disease between 1987 and 2002 were identified. Tumor and treatment characteristics and toxicities were recorded. Progression-free survival and overall survival estimates were generated. The influence of prognostic factors was determined.ResultsTwelve patients were analyzable. Brachytherapy was given curatively (n = 4) in patients not amenable to surgery or in combination with surgical dissection to avoid carotid resection (n = 8). Seven patients had disease progression with a median time to progression of 11 months (95% confidence interval: 0–22.9). The only negative prognostic factor was time to re-treatment (brachytherapy >4 months) after definitive treatment (p = 0.003). Overall survival at 1 and 5 years was 50% and 21%, respectively. Toxicity was limited to one major complication (fistula) and five minor toxicities: low-grade radionecrosis (n = 2), cellulitis (n = 1), and wound dehiscence (n = 2).ConclusionIn patients with persistent disease, brachytherapy is an appealing re-treatment alternative. When combined with neck dissection, brachytherapy yields less morbidity than the surgical alternative of carotid resection.     

头颈部恶性肿瘤放疗后颈动脉狭窄的研究进展

头颈部恶性肿瘤是常见的恶性肿瘤,放射治疗是头颈部恶性肿瘤的重要治疗手段之一。随着治疗手段的进步,患者生存期明显延长,同时放疗引起的颈动脉狭窄也越来越受到医生及患者的关注。放疗引起的颈动脉狭窄是多种因素作用的结果,目前应用比较广泛的检查手段为彩色超声多普勒及颈动脉听诊,经皮血管成形术及支架植入术为主要的治疗手段。笔者主要针对头颈部恶性肿瘤放疗后引起颈动脉狭窄的发病率、发病机制、相关危险因素、诊断及治疗原则等方面进行综述。     

胸腺肿瘤质子碳离子放疗的剂量对比研究及短期疗效观察

目的对比光子和质子碳离子(粒子)放疗计划在有可见胸腺肿瘤患者中危及器官受量的差异,并观察粒子射束放射治疗胸腺肿瘤的近期疗效和不良反应。方法回顾性分析19例于2015年9月至2018年8月接受非姑息性粒子放疗、至少经过1次随访的胸腺肿瘤患者。肿瘤分期涵盖Ⅰ~ⅣB期,其中Ⅲ~ⅣB期15例。所有患者均经病理学证实,包括10例胸腺瘤,6例胸腺癌和3例胸腺神经内分泌肿瘤。对13例有可见肿瘤的患者进行光子调强、质子和碳离子笔形束扫描放疗计划对比,光子和质子的处方为66 GyE/33次,碳离子为66 GyE/22次。未经手术的5例初治和7例术后肉眼肿瘤残留(R2切除)患者,接受根治性放疗:质子44.0~48.4 GyE/20~22次加碳离子推量21.0~23.1 GyE/7次;1例完整切除(R0)术后患者,质子45 GyE/25次;5例术后显微镜下残留(R1切除)者,质子60.0~61.6 GyE/28~30次;1例术后放疗后复发者,碳离子60 GyE/20次。结果中位随访时间19.0(2.4~42.9)个月。13例可见肿瘤患者肿块最大径中位数5.7(2.7~12.8)cm;剂量对比研究显示粒子计划可显著降低脊髓最大剂量、肺、心、食管等危及器官的平均剂量、以及受照区域积分剂量,仅约为光子计划的25%~65%。除1例心肌梗死(4级晚期反应)可能与放疗相关外,未发现其他≥3级放疗相关不良反应。所有患者无局部复发,4例Ⅲ~ⅣB期患者在放疗开始后6.1~22.8个月出现区域淋巴结、肺、胸膜、颅底、骨和肝等部位转移。2年局部控制率和总生存率均为100%,无疾病进展生存率和无远处转移生存率均为64.6%。结论对胸腺肿瘤的剂量对比分析显示,质子碳离子放疗的正常组织受量仅为光子计划的25%~65%;临床结果提示短期疗效好、不良反应轻微。     

质子治疗机房的屏蔽设计方案国内外比较

目的 探讨国内外不同辐射防护标准对质子治疗机房屏蔽设计的影响。方法 以一个多室质子中心机房为例,分别根据美国国家辐射防护与测量委员会（NCRP）151号报告、新加坡辐射防护法案、英国ACoP指南以及国家标准GBZ/T 201.5-2015规定的辐射防护限值,得到相应的屏蔽方案。比较各个机房间隔墙和机房与控制室间隔墙厚度,在保持各个机房设计尺寸不变的前提下,从机房有效使用面积、建设成本等方面讨论上述4种屏蔽方案的差异性。结果 由NCRP 151号报告计算得到的各机房墙体（A~F）厚度最薄,由国家标准计算得到的墙体厚度最厚,其中两个旋转治疗室间隔墙厚度增加了1倍以上,总的治疗室使用面积减少17.69%,总建筑材料成本增加44万元。结论 通过比较不同屏蔽标准对质子治疗机房设计的影响,发现与其他国际法规或标准相比,我国现行的质子机房辐射屏蔽标准远高于其他国家,这会显著增加机房的屏蔽墙厚度,对国内的质子治疗技术的发展及将来升级到超高剂量率治疗模式都有一定影响。建议参考质子治疗技术相对成熟的国家标准和经验,适当放宽瞬时剂量率限值条件,增加更能反映现实治疗工况的时间平均剂量率（time averaged dose rate,TADR）限值条件,以更好地实现机房屏蔽设计的最优化原则。     

Intensity-modulated proton therapy (IMPT) versus intensity-modulated radiation therapy (IMRT) for the treatment of head and neck cancer: A dosimetric comparison

It is the goal of this study to compare the dosimetric advantages of IMPT when compared to IMRT. From January 2019 to August 2020, 25 patients were treated with intensity modulated proton therapy (IMPT) at our institution for either recurrent, metastatic, benign, or primary tumors in the head and neck region. Twenty-one patients met criteria for dosimetric analysis. Histology of disease included squamous cell carcinoma, acinic cell carcinoma, sarcomatoid sinonasal carcinoma, paraganglioma, adenoid cystic carcinoma, salivary high grade carcinoma, and papillary thyroid carcinoma. For IMRT planning, gross tumor volume (GTV) and clinical target volume (CTV) were contoured with the expansion of 3-5 mm to create the planning target volume (PTV) and dose was prescribed to the PTV. For the IMPT planning, dose was prescribed to CTV and robust optimization was utilized which accounted for a 5 mm setup and range uncertainty. The minimum, mean and maximum target doses for IMRT and IMPT plans as well as mean and maximum normal tissue doses are reported for the 21 patients meeting criteria. Mean doses for IMRT and IMPT were 6278.2 cGy and 6449.8 cGyRBE respectively with p-value of 0.0001. Maximum doses for IMRT and IMPT were 6579.5 cGy and 6772.1 cGyRBE respectively with p-value of 0.0014. Minimum doses for IMRT and IMPT were 5440.6 cGy and 5617.9 cGyRBE respectively with p-value of 0.3576. IMPT had an overall advantage in OAR doses in the brain stem, spinal cord, optic structures, cochlea, larynx, contralateral parotid, and oral cavity with only a few exceptions. Our study thus demonstrates a dosimetric advantage for IMPT in treating head and neck tumors in mean and max dose delivered as well as dose to OARs. Given that our patient cohort were mainly unilateral head and neck cases, our study supports the treatment of this specific subset of patients regardless of histology with IMPT. This may aid in appropriate patient selection for IMPT treatment. Further studies will need to determine if this dosimetric advantage translates to a therapeutic advantage for patients.     

铋屏蔽对头颈部多层螺旋CT中眼晶状体辐射剂量的降低作用

目的 探讨扫描平面内铋屏蔽在头颈部多层螺旋CT(MSCT)扫描中对影像质量的影响和眼晶状体辐射剂量的降低作用.方法 分别使用颅脑、颞骨和鼻窦临床扫描条件,在无屏蔽、1层、2层和3层铋屏蔽覆盖眼部区域时,对标准水模和离体头颅标本进行扫描,用热释光剂量片测量头颅标本每次扫描时的眼晶状体器官剂量.在屏蔽材料和被扫描体间放置5、10、15和20 mm厚的海绵时,使用鼻窦扫描条件采集影像,并测量眼晶状体的剂量.测量水模影像中与屏蔽物为2、4、6和8 cm距离处的CT值,主观评价头颅标本影像中伪影对解剖结构的影响.结果 颅脑、颞骨和鼻窦CT临床扫描中眼晶状体的器官剂量分别为24.31、27.60和20.01 mGy.使用铋屏蔽时,均使得眼晶状体剂量有显著下降,但下降幅度随着铋屏蔽物的增加而降低.在各种厚度的屏蔽物时,屏蔽物间隙越大,眼晶状体剂量的降低程度越小,测量兴趣区CT值的增加程度也显著降低.颅脑和颞骨CT扫描分别使用2层和3层铋屏蔽,在不影响诊断的前提下,可有效降低眼晶状体剂量分别为47.1%和59.1%;鼻窦CT扫描时,1层屏蔽无间隙、2层屏蔽1.5 cm间隙不影响诊断,可降低眼晶状体剂量分别为31.5%和34.5%.结论 扫描平面内铋屏蔽材料的合理应用,可有效降低头颈部CT扫描中眼晶状体的辐射剂量.     

Impaired swallowing mechanics of post radiation therapy head and neck cancer patients: A retrospective videofluoroscopic study

AIM: To determine swallowing outcomes and hyolaryngeal mechanics associated with post radiation therapy head and neck cancer (rtHNC) patients using videofluoroscopic swallow studies.METHODS: In this retrospective cohort study, videofluoroscopic images of rtHNC patients (n = 21) were compared with age and gender matched controls (n = 21). Penetration-aspiration of the bolus and bolus residue were measured as swallowing outcome variables. Timing and displacement measurements of the anterior and posterior muscular slings elevating the hyolaryngeal complex were acquired. Coordinate data of anatomical landmarks mapping the action of the anterior muscles (suprahyoid muscles) and posterior muscles (long pharyngeal muscles) were used to calculate the distance measurements, and slice numbers were used to calculate time intervals. Canonical variate analysis with post-hoc discriminant function analysis was performed on coordinate data to determine multivariate mechanics of swallowing associated with treatment. Pharyngeal constriction ratio (PCR) was also measured to determine if weak pharyngeal constriction is associated with post radiation therapy.RESULTS: The rtHNC group was characterized by poor swallowing outcomes compared to the control group in regards to: Penetration-aspiration scale (P < 0.0001), normalized residue ratio scale (NRRS) for the valleculae (P = 0.002) and NRRS for the piriform sinuses (P = 0.003). Timing and distance measurements of the anterior muscular sling were not significantly different in the two groups, whereas for the PMS time of displacement was abbreviated (P = 0.002) and distance of excursion was reduced (P = 0.02) in the rtHNC group. A canonical variate analysis shows a significant reduction in pharyngeal mechanics in the rtHNC group (P < 0.0001). The PCR was significantly higher in the test group than the control group (P = 0.0001) indicating reduced efficiency in pharyngeal clearance.CONCLUSION: Using videofluoroscopy, this study shows rtHNC patients have worse swallowing outcomes associated with reduced hyolaryngeal mechanics and pharyngeal constriction compared with controls.     

In vivo proton MR spectroscopy of primary tumours,nodal and recurrent disease of the extracranial head and neck

Benign and malignant neoplasms as well as metastatic lymph nodes of 39 patients were examined using localized single voxel magnetic resonance spectroscopy (MRS) [repetition time (TR) 1500, echo time (TE) 135) at 1.5 T. New techniques with simultaneous correction of motion artefacts during the acquisition, three-dimensional saturation pulses, respiratory triggering and smaller volume of interest (VOI) size, were applied. Ratios of peak areas under the choline (Cho) and creatine (Cr) resonances were estimated in all cases and compared with those from samples of normal tissue. Ninety one spectra were acquired in 39 patients, 63 of which were suitable for further evaluation. The smallest VOI was 0.40 cm³. The Cho/Cr ratios in all malignant neoplasms (mean: 5.2, range: 1.7–17.8) were significantly elevated relative to those in the normal muscle structures (mean: 0.9, range: 0.2–1.4), while those in the benign neoplasms were elevated (mean: 24.4, range: 1.4–59.7) with respect to those in the malignant ones. The average Cho/Cr ratio in the metastatic lymph nodes was significantly higher (mean: 4.8, range: 3.3–5.6) than that for benign lymphoid hyperplasia (mean: 2.2, range: 1.0–3.0). MRS measurements were able to differentiate recurrent disease from post-therapeutic tissue changes in 11 out of 13 patients.     

头颈部肿瘤放疗过程中腮腺变化对照射剂量影响的研究

目的 分析头颈部肿瘤患者螺旋断层放疗过程中腮腺位置、体积变化对受照剂量的影响.方法 12例头颈部肿瘤根治性放疗患者,每次治疗前行MVCT图像配准,选择每周第1天MVCT图像,应用TomoTherapy系统自带软件和MIM系统,计算腮腺体积、位置变化和实际照射剂量.结果 与初始计划相比,放疗结束时左、右两侧腮腺体积分别缩小29.06%和31.78%(Z=6.77、3.06,P<0.05),腮腺质心距离体中线距离分别缩小6.72%和6.19%(t=5.14、5.80,P<0.05).治疗过程中左侧腮腺V₂₆、平均剂量分别增加37.74%、25.08%(Z=-6.03、-5.31,P<0.05),右侧腮腺V₂₆、平均剂量分别增加30.45%、19.33%(Z=-5.43、-3.26,P<0.05).结论 头颈部肿瘤放疗过程中腮腺实际受照剂量较初始计划明显升高,剂量升高与腮腺向体中线位移密切相关,与腮腺体积缩小无明显相关性.适时重新制定放疗计划或行自适应放疗,可减少腮腺受照剂量.     

利用EBT3胶片测量主动式点扫描质子重离子放疗设备照射野一致性研究

目的 研究主动式点扫描质子重离子加速器所形成照射野的一致性的检测方法。方法 在标定过的离子束流下进行EBT3胶片刻度,建立EBT3胶片的剂量刻度曲线,然后在4个治疗室中,EBT3胶片放置于固体水模体中进行照射,胶片位置针对质子和碳离子不同能量（质子：94.29、150.68和212.62 MeV;碳离子：175.99、283.43和412.54 MeV/u）前后放置不同厚度的固体水模体插板,最后扫描EBT3胶片图像,分析照射野剂量分布大小和规定照射野大小的差异及平坦度。结果 4个治疗室,不同条件下照射野一致性检测的照射野大小均<2 mm,平坦度均控制在5%之内。结论 EBT3胶片可以检测主动式点扫描质子重离子加速器的照射野一致性。     

Serial FDG-PET on patients with head and neck cancer: Implications for radiation therapy

Purpose: To assess possible consequences for radiotherapy (RT) planning, e.g., reduction of treatment volume by a decreased tumour volume in Fluor-18-fluoro-deoxy-glucose-Positron emission tomography (FDG-PET) based on a close-meshed evaluation of FDG uptake in primary head and neck cancer (HNC) during RT.

Materials and method: PET data were analysed using a source-to-background based algorithm. The following parameters were obtained: max. standardised uptake value (SUVmax), PET-based gross tumour volume (GTV-PET) and metabolic volume (MV).

Results: While the median SUVmax decreased (initial: 15.2, 1st/2nd week: 10.2, 3rd/4th week: 6.5, 5th/6th week: 6.4), the median values of GTV-PET (9.3 cm³, 12.4 cm³, 14.0 cm³, 17.9 cm³) and MV (92.2 cm³, 61.7 cm³, 60.0 cm³, 71.3 cm³) seemed to increase during radiotherapy. The intra-individual development of SUVmax could be divided into two groups: group A having continuously decreasing values of SUVmax (n = 10 patients), and group B having a temporary increase of SUVmax (n = 13).

Conclusions: Data suggest that a reduction of treatment volume is not possible by an adaptive re-planning based on FDG-PET, e.g., at 50 Gy. This may be caused by a consecutive therapy associated inflammation. This limitation is probably related to the use of a source-to-background based algorithm.     

头颈部肿瘤三维适形放射治疗中的质量保证

目的探讨头颈部肿瘤3D—CRT实施过程的质量控制(QC)方法。方法采用拓能系统的固定装置、计划系统、激光灯、弓形尺、头部模型(简称头模)模拟3D—CRT的实施过程进行质量控制分组实验。结果复位标记标在固定装置以及面罩开窗处患者皮肤上的B组，实施过程误差小于复位标志标注在面罩上的A组。能达到3D—CRT过程QC要求。结论开展头颈部肿瘤3D—CRT必须合理使用头部固定装置。严格按本文规定标准方法操作可达到3D—CRT的实施过程的QC要求。     

外放疗联合个体化导板辅助 125I放射性粒子植入治疗晚期头颈部鳞癌

目的：探讨外放疗联合个体化导板辅助¹²⁵I放射性粒子植入治疗无法手术的头颈部鳞癌的可行性及不良反应。 方法：对17例因全身系统疾病而无法手术的头颈部鳞癌患者进行常规分割放疗联合个体化导板辅助¹²⁵I放射性粒子植入增量放疗。外放疗总照射剂量为50 Gy,放射性粒子匹配周缘剂量（matched peripheral dose, MPD）为80~120 Gy。 结果：通过肿瘤体积变化情况和临床表现评价治疗标准,17例患者治疗总有效率达到82.4%（14/17）,1例死于大出血。主要的不良反应包括：软组织坏死、局部出血及放射性黏膜炎和皮炎等,治疗过程未发生急性并发症与严重的放射性损伤。 结论：外放疗联合个体化导板辅助¹²⁵I放射性粒子植入治疗晚期头颈部鳞癌,是一种微创、有效、安全性高的治疗方案。