局部晚期直肠癌两组术前放疗剂量方案短期疗效分析

目的 评估局部晚期直肠癌新辅助放化疗不同放疗剂量短期疗效差异及耐受性。方法 回顾性分析2010年8月至2015年5月在本院接受新辅助放化疗的局部晚期直肠癌患者。根据放疗剂量分为46和50 Gy两组,同步化疗方案以卡培他滨为基础,<75岁且一般情况较好的患者联合奥沙利铂,所有患者完成新辅助放化疗和直肠癌根治术。结果 共有213例患者纳入研究,其中2010年8月至2013年8月接受46 Gy放疗剂量治疗61例,2013年9月至2015年5月接受50 Gy放疗剂量治疗152例,其中男性145例,女性68例;T₂期22例,T₃期180例,T₄期11例;下、中、上段直肠癌分别为82、115和16例。两组患者年龄、性别、治疗前T分期及N分期差异无统计学意义（P>0.05）,临床特征匹配。50和46 Gy组病理完全缓解（PCR）率分别为24.3%和18.0%（P>0.05）;病理缓解良好（GR）率分别为75.0%和67.2%（P>0.05）;T降期率分别为46.7%和39.3%（P>0.05）。T₃N₂/T₄亚组分析：50和46 Gy组CR率分别为23.3%和6.3%（P>0.05）;GR （病理消退分级3+4）率分别为72.1%和50.0%,差异无统计学意义（P>0.05）。T降期率为46.5%和31.3%,差异无统计学意义（P>0.05）。结论 50 Gy较46 Gy放疗剂量治疗局部晚期直肠癌未能提高肿瘤病理缓解率及T降期率,对T₃N₂/T₄期患者,两组差异也无统计学意义,远期疗效有待进一步随访验证。     

鼻咽癌增量时间调节化疗加后程三维适形放射治疗的临床研究

目的 探讨顺铂+5-氟尿嘧啶/亚叶酸钙（DDP+5-FU/CF）增量时间调节化疗加后程三维适形放疗治疗鼻咽癌的疗效。方法 2006年3月至2007年10月收治60例鼻咽癌患者,按信封法随机分为两组：增量时间调节化疗加后程三维适形放疗（3D-CRT）组（时辰组）和常规放化疗组（常规组）,每组30例。所有病例均先采用两周期诱导化疗后行单纯放疗。两组化疗方案及用药剂量相同,DDP总量100 mg/m²,5-FU 1 g/m²·d,连用3 d,14 d为1个周期,共2个周期。两组化疗后均用直线加速器给予鼻咽部相同的放疗剂量D_T70 Gy/7周,2 Gy/次,5次/周。鼻咽部应用面颈联合野常规放疗D_T 36 Gy/4周后,常规组缩野改为常规耳前野放疗D_T 34 Gy/3~4周,时辰组改为后程三维适形放疗D_T34 Gy/3~4周。结果 时辰组完全缓解率（CR）及有效率（CR+PR）分别为50%和100%,高于常规组的23.3%和93.3%,其中CR的差异有统计学意义（χ² =4.593,P<0.05）。1、 3、 5年总生存率及无疾病生存率两组的差异无统计学意义。相对于常规组,时辰组化疗的骨髓及消化道不良反应减低（χ²=4.285、4.344,P<0.05）。结论 DDP+5-FU/CF增量时间调节化疗加后程三维适形放疗较常规放化疗能减轻骨髓及消化道的不良反应,提高鼻咽癌的完全缓解率,但未降低远期生存率。     

144例鼻咽癌常规放疗后鼻窦炎发生的因素分析

目的 探讨鼻咽癌患者常规放疗后鼻窦炎的发生情况及其影响因素。方法 回顾分析本院2000—2005年收治的放疗前无鼻窦炎而放疗后发生鼻窦炎的144例鼻咽癌患者资料,并就其影响因素进行分析。鼻窦炎的诊断用MRI法。T₁+T₂期82例,T₃+T₄期62例。鼻腔受侵58例,无鼻腔受侵86例。鼻咽灶为面颈联合野6 MV X线常规分割照射68~78 Gy, 6~8周,其中>70 Gy 55例、≤70 Gy 89例。颈部为6 MV X线+高能电子线照射,淋巴结阳性者64~74 Gy, 6~8周;阴性者50~54 Gy, 4~5周。结果 全组患者放疗后鼻窦炎总的发生率为86.8%(125例),其中T₃+T₄期的高于T₁+T₂期的,分别为94%(58例)和82%(67例),差异有统计学意义(χ²=4.32, P<0.05);鼻咽灶剂量>70 Gy的高于≤70 Gy的,分别为95%(52例)和82%(73例),差异有统计学意义(χ²=4.65, P<0.05) ;鼻腔受侵的高于未受侵的,分别为95%(55例)和81%(70例),差异有统计学意义(χ²=5.46, P<0.05)。鼻窦炎发生在放疗后3、6、12、>12个月的比例不同,分别占13.6%(17例)、31.2%(39例)、48.8%(61例)及6.4%(8例),差异有统计学意义(χ²=70.48, P<0.01)。结论 鼻咽癌患者常规放疗后鼻窦炎的发生率较高,并在1年内达最高峰;鼻腔有无侵犯、鼻咽照射剂量和T分期与放疗后鼻窦炎的发生有关。     

宫颈癌术后限定骨髓剂量盆腔调强放疗的临床研究

目的 观察宫颈癌患者术后限定骨髓剂量的盆腔调强放疗(BMS-IMRT)与非限定骨髓剂量的盆腔调强放疗(IMRT)联合化疗的近期疗效及不良反应。方法 本院宫颈癌术后患者70例,用抽签方法随机分为BMS-IMRT组34例和IMRT组36例,行盆腔外照射调强放疗联合化疗,计划靶体积剂量45 Gy分25次。BMS-IMRT组勾画骨盆并给予单独限量:骨盆V₃₀≤50%;70例患者同期每周40 mg/m²顺铂化疗。结果 除3例因重度骨髓抑制未完成化疗外,67例患者顺利完成治疗。两组2年的局部控制率及生存率、下消化道及泌尿系统不良反应差异无统计学意义,BMS-IMRT组血液学不良反应较IMRT组轻,差异有统计学意义(χ²=14.355,P<0.05)。结论 宫颈癌术后行盆腔同步放化疗患者,BMS-IMRT组较IMRT组血液学不良反应减轻,近期疗效及其他放疗不良反应无明显差异。     

早期乳腺癌保乳术后放化疗顺序临床分析

目的 分析191例早期乳腺癌保乳术后患者,探讨不同放化疗顺序对不同高危因素患者预后的影响。方法 回顾性分析自2006年1月1日至2015年12月31日大连医科大学附属第二医院收治的191例早期乳腺癌保乳术后患者（T_1-2N_0-1M₀）临床资料。按放化疗顺序分为先放疗组、先化疗组和化疗-放疗-化疗组（"三明治组"）。先放疗组32例、先化疗组107例、三明治组52例。对各组病例的年龄、是否绝经、肿瘤大小（T₁、T₂）、淋巴结转移情况、病理学类型、脉管癌栓、分子分型、手术放疗间隔时间等因素进行单因素及多因素分析,寻找影响患者预后的独立危险因素。比较存在不同高危因素的患者在先放疗组、先化疗组、三明治组中5年局部复发（LRR）和总生存（OS）的差异。结果 肿瘤大小、淋巴结转移情况、脉管癌栓、手术放疗间隔时间是影响5年OS的独立危险因素。先放疗组、先化疗组、三明治组中T₁、T₂期患者的5年LRR和OS比较,差异均无统计学意义（P>0.05）。先放疗组、先化疗组与三明治组淋巴结转移N₀期患者5年LRR比较,差异无统计学意义（P>0.05）。先化疗组和三明治组N₁期患者5年LRR分别为4.5%和16.2%,两组差异有统计学意义（χ²=4.813,P=0.028）。先化疗组和三明治组N₁患者5年OS差异无统计学意义（P>0.05）。先放疗组、先化疗组、三明治组有脉管癌栓患者5年LRR分别为5.3%、9.2%、18.1%（P>0.05）;5年OS分别为61.5%、90.1%、87.2%（χ²=6.282,P=0.043）。3组无脉管癌栓患者5年LRR、OS比较,差异均无统计学意义（P>0.05）。先放疗组、先化疗组、三明治组手术放疗间隔时间≤ 6个月的患者5年LRR差异均无统计学意义（P>0.05）。手术放疗间隔时间>6个月均为先化疗组,先化疗组中手术放疗间隔≤ 6个月与>6个月患者的5年LRR为5.2%和14.1%（χ²=4.886,P=0.027）,OS分别为96.9%和85.7%（χ²=5.758,P=0.038）。结论 临床治疗时根据个体化选择方案。对于腋窝淋巴结阴性而局部存在复发高危因素的患者,可以先进行放疗;对于腋窝淋巴结转移或脉管癌栓的高危患者,应早期开始化疗,放疗可以延迟,但不能超过6个月。     

容积旋转调强与固定野调强在晚期宫颈癌放疗的剂量学比较及疗效观察

目的 比较容积旋转调强（RapidArc）和固定野调强（IMRT）技术在宫颈癌根治性放疗的剂量学参数、急性不良反应发生率及疗效。方法 回顾性分析43例局部晚期（II_b~IV）宫颈癌患者,其中22例行容积旋转调强放疗,21例行固定野调强放疗,处方剂量50.4 Gy/28次,比较两组靶区剂量适形度、均匀性、靶区及危及器官的剂量、机器跳数及治疗时间;对比两组患者治疗期间的急性肠道及膀胱反应发生率;对比两组患者的完全缓解率和有效率。结果 与IMRT计划相比,RapidArc计划的靶区适形性指数CI略好,但差异无统计学意义（P > 0.05）;两组计划的靶区均匀性指数HI比较,差异无统计学意义（P > 0.05）。RapidArc计划中膀胱的V₄₀、V₅₀以及直肠的V₃₀、V₄₀、V₅₀均低于IMRT计划（t=-2.386、-2.397、-5.525、-2.883、-2.686,P < 0.05）,RapidArc计划中股骨头的平均剂量低于IMRT计划（t=-2.395,P < 0.05）。RapidArc较IMRT平均MU减少了53.15%,治疗所需平均时间缩短了62.14%。两组患者肠道、膀胱急性反应发生率相近。两组患者完全缓解率和有效率相近。结论 晚期宫颈癌根治性放疗中,采用RapidArc技术可以降低危及器官受量,缩短患者的治疗时间。     

术后辅助放疗对N2期非小细胞肺癌患者预后的影响

目的 探讨术后辅助放疗对N₂期行肺癌根治术的非小细胞肺癌（NSCLC）患者预后的影响。方法 将美国SEER数据库2004-2016年间收录的接受肺癌根治术联合化疗或术后辅助放化疗的N₂期1 208例非小细胞肺癌患者资料纳入研究,其中接受肺癌根治术联合化疗的有627例（手术+化疗组）,接受肺癌根治术联合放化疗的有581例（手术+放化疗组）。分析并比较术后辅助放疗对N₂期行肺癌根治术的非小细胞肺癌患者预后的影响,同时采用1：1倾向性匹配方法分析两组患者预后情况。结果 纳入研究的两组N₂期非小细胞肺癌患者中,手术+放化疗组患者中位生存期为51月,3年、5年肿瘤特异性生存分别为58.3%、44.9%;手术+化疗组患者中位生存期为50月,3年、5年肿瘤特异性生存分别为59.9%、46.5%;两组患者的肿瘤特异性生存差异无统计学意义（P>0.05）;亚组分析发现,T₁期患者中手术+放化疗组的特异性生存明显差于手术+化疗组（χ²=5.085,P<0.05）;多因素Cox回归分析提示,年龄、性别、G分期、T分期及淋巴结转移数目是影响N₂期非小细胞肺癌患者肿瘤特异性生存的重要因素（Wald=15.236、7.039、4.841、10.155、11.192,P<0.05）。倾向性评分匹配两组N₂期非小细胞肺癌患者后分析发现,手术+放化疗组与手术+化疗组的肿瘤特异性生存差异无统计学意义（P>0.05）;而T₁期NSCLC患者中手术+放化疗组的特异性生存明显差于手术+化疗组（χ²=5.364,P<0.05）,而T_3~4期的亚组手术+放化疗组的肿瘤特异性生存明显优于手术+化疗组（χ²=4.486,P<0.05）;针对病理亚组倾向性匹配后发现,非腺癌亚组中手术+放化疗组的肿瘤特异性生存亦明显优于手术+化疗组（χ²=6.279,P<0.05）。多因素Cox回归分析也提示,术后放疗的加入是影响N₂期肺非腺癌患者肿瘤特异性生存的重要因素（Wald=7.300,P<0.05）;但肺腺癌亚组患者倾向性匹配后手术+放化疗组与手术+化疗组肿瘤特异性生存之间差异无统计学意义（P>0.05）。结论 术后辅助放疗能够改善T_3~4期或者非腺癌N₂期非小细胞肺癌患者的预后。而对T₁期术后辅助放疗选择仍需谨慎。     

食管癌临床分期对三维适形放射治疗预后的影响

目的 分析食管癌三维适形放射治疗的预后影响因素,评价食管癌临床分期对判断预后的价值。方法回顾性分析资料完整的81例接受三维适形放疗的食管癌患者,对可能影响预后的因素进行多因素分析,并比较肿瘤局部T分期、N分期和临床分期与预后的关系。结果全组患者1、2、3、4年总生存率分别为67.9%、45.7%、40.5%和30.9%,1、2、3、4年局部控制率分别为83.0%、76.1%、73.9%和69.8%。放疗前X射线病变长度、病变局部T分期、临床分期、食管GTVD₉₅为影响患者总生存率的独立预后因素。T₁+T₂期与T₃、T₄期比较,临床Ⅰ+Ⅱ与临床Ⅲ、Ⅳ期比较,总生存率、局部控制率、无远处转移生存率及无瘤进展生存率的差异均有统计学意义。N₀期与N₁、N₂期比较,除局部控制率外,总生存率、无远处转移生存率及无瘤进展生存率差异均有统计学意义。临床Ⅲ期与Ⅳ期之间除局部控制率差异无统计学意义外(χ²=2.03,P=0.155),总生存率、无远处转移生存率及无瘤进展生存率比较差异均有统计学意义(χ²值分别为5.38、4.26、3.96,P值分别为0.020、0.039、0.045 )。结论食管癌临床分期的四分类法是非手术治疗食管癌比较理想的分期方法,能较好地预示放射治疗的预后。     

新辅助放疗与辅助放疗对T3N0期食管癌患者疗效的对比

目的 通过对美国SEER数据库2004-2014年收录的术前或术后行放疗的食管癌根治术患者资料,探讨新辅助放疗与辅助放疗对T₃N₀期行食管癌根治术患者疗效。方法 将美国SEER数据库2004-2014年间收录的接受术前放疗或术后放疗的行食管癌根治术的555例T₃N₀期患者资料纳入研究,其中接受新辅助放疗的有486例（新辅助放疗组）,接受术后辅助放疗的有69例（辅助放疗组）。分析并比较新辅助放疗与辅助放疗对T₃N₀期行食管癌根治术患者疗效,同时采用1：1倾向性匹配方法分析两组患者的疗效。结果 新辅助放疗组肿瘤特异性生存明显优于辅助放疗组（χ²=6.030,P<0.05）;多因素COX回归分析提示年龄、性别及放疗顺序是影响预后的重要因素（Wald=10.099、10.562、4.331,P<0.05）,其中辅助放疗组肿瘤特异性死亡风险及总体死亡风险分别是新辅助放疗组的1.649（95%CI 1.173~2.316,P=0.004）倍、1.402（95%CI 1.020~1.928,P=0.037）倍。1：1倾向性匹配后分析提示,新辅助放疗组肿瘤特异性生存率明显优于辅助放疗组（χ²=6.293,P<0.05）。结论 与术后辅助放疗相比,新辅助放疗能够改善T₃N₀期食管癌患者的预后,具有重要的临床价值。     

局部晚期直肠癌术前同步放化疗中卡培他滨联合奥沙利铂剂量递增的I期临床研究

目的 探讨局部晚期直肠癌术前同步放化疗基于5-Fu类药物的联合方案中奥沙利铂的最大耐受剂量。方法 本试验设计为前瞻性研究,自2015年3月至2015年10月,入组经病理确诊的局部晚期（T₃、T₄/N+）直肠癌患者15例,接受调强放疗以及卡培他滨联合奥沙利铂方案的同步化疗。放疗采用同步局部加量, 总剂量GTV为50.6 Gy,CTV 41.8 Gy,共22次,30 d内完成。同期化疗,卡培他滨为固定剂量825 mg/m²,2次/d,每周1~5服用,伴随放疗全程;奥沙利铂剂量分别为100、110、120、130 mg/m²,共4个递增剂量水平组,每21天为1个周期。15例患者,前12例按随机数字表法分为4组,每组3例,最后一组因出现剂量限制性毒性又入组了3例患者,因此,第4组为6例。治疗后充分评估不良反应和有效率。结果 近期治疗相关不良反应主要表现为放射性肠炎、皮肤反应、恶心、乏力、泌尿系不良反应和骨髓抑制,并随奥沙利铂剂量的提高而增多、加重。观察100、110 和120 mg/m²组中未出现3级以上不良反应,130 mg/m²组中则出现了剂量限制性毒性：1例3级血小板减少和1例3级恶心,该剂量为最大耐受剂量。手术后病理显示,所有患者均达到降期,4组患者分别有0、1、2、3例达到完全缓解。结论 局部晚期直肠癌调强放疗同步联合卡培他滨及奥沙利铂方案安全有效。奥沙利铂的最大耐受剂量为130 mg/m²,1次/3周。     

Conventional 2D (2DRT) and 3D conformal radiotherapy (3DCRT) versus intensity-modulated radiotherapy (IMRT) for nasopharyngeal cancer treatment

Purpose

Nasopharyngeal carcinoma represents a distinct entity as compared to other head and neck tumours. Radio-chemotherapy is the treatment of first choice in non-metastatic disease. Intensity-modulated radiation therapy (IMRT) allows the sparing of parotid glands, improving the toxicity profile. The aim of this study was to compare the results obtained with IMRT with those obtained with conventional 2D (2DRT) and 3D conformal radiation therapy (3DCRT) in terms of tumour control, survival, acute and late toxicity.

Materials and methods

We reviewed the clinical records of 52 patients with histologically proven carcinoma of the nasopharynx (stage I–IVB according to the 2002 American Joint Committee on Cancer staging system) treated with curative intent between January 2003 and August 2011: 26 patients were treated with 2D or 3D technique (arm A) and 26 with IMRT technique (arm B) with simultaneous integrated boost. Fifty patients (96 %) received chemotherapy. Local control (LC), locoregional control (LRC), disease-free survival (DFS), overall survival (OS), acute and late toxicity were retrospectively evaluated.

Results

After a median follow-up of 37.6 months (69 months in arm A and 23 months in arm B), 69 % of patients were alive and disease-free, 10 % were alive with disease and 21 % died of disease, with an OS of 81 % at 2 years and 79 % at 5 years, a LC rate of 88 % at 2 years and 78 % at 5 years, a LRC rate of 80 % at 2 years and 73 % at 5 years and a DFS of 74 % at 2 years and 65 % at 5 years, with no statistically significant differences between IMRT and 2DRT/3DCRT. In multivariate analysis, the TNM stage and the volume treated at high dose correlated with DFS. No factor was found to be related to OS. Chronic toxicity was not statistically different in the two study groups and in particular ≥G2 xerostomia rates were 67 and 41 % in arm A and B, respectively (p = 0.10).

Conclusions

The findings of this study confirm that IMRT associated with chemotherapy, even with moderately hypofractionated regimens, allows good disease control with better results in terms of late xerostomia, although without statistically significant differences compared to 2DRT and 3DCRT. The hypothesis of an impact of IMRT on survival has yet to be confirmed.     

Single-arc volumetric-modulated arc therapy (sVMAT) as adjuvant treatment for gastric cancer: Dosimetric comparisons with three-dimensional conformal radiotherapy (3D-CRT) and intensity-modulated radiotherapy (IMRT)

To compare the dosimetric differences between the single-arc volumetric-modulated arc therapy (sVMAT), 3-dimensional conformal radiotherapy (3D-CRT), and intensity-modulated radiotherapy (IMRT) techniques in treatment planning for gastric cancer as adjuvant radiotherapy. Twelve patients were retrospectively analyzed. In each patient's case, the parameters were compared based on the dose-volume histogram (DVH) of the sVMAT, 3D-CRT, and IMRT plans, respectively. Three techniques showed similar target dose coverage. The maximum and mean doses of the target were significantly higher in the sVMAT plans than that in 3D-CRT plans and in the 3D-CRT/IMRT plans, respectively, but these differences were clinically acceptable. The IMRT and sVMAT plans successfully achieved better target dose conformity, reduced the V_20/30, and mean dose of the left kidney, as well as the V_20/30 of the liver, compared with the 3D-CRT plans. And the sVMAT technique reduced the V₂₀ of the liver much significantly. Although the maximum dose of the spinal cord were much higher in the IMRT and sVMAT plans, respectively (mean 36.4 vs 39.5 and 40.6 Gy), these data were still under the constraints. Not much difference was found in the analysis of the parameters of the right kidney, intestine, and heart. The IMRT and sVMAT plans achieved similar dose distribution to the target, but superior to the 3D-CRT plans, in adjuvant radiotherapy for gastric cancer. The sVMAT technique improved the dose sparings of the left kidney and liver, compared with the 3D-CRT technique, but showed few dosimetric advantages over the IMRT technique. Studies are warranted to evaluate the clinical benefits of the VMAT treatment for patients with gastric cancer after surgery in the future.     

老年人晚期非小细胞肺癌三维立体适形放射治疗

目的 探讨老年人非小细胞肺癌(NSCLC)三维立体适形放射治疗(3D-CRT)的临床特点和疗效.方法 对108例由于内科禁忌证或其他情况不能手术的老年人晚期NSCLC施行3D-CRT,单次剂量5～8Gy,隔日1次,总剂量68～82Gy.结果 108例全部完成放射治疗计划,1、2、3年的平均生存率分别为65%、33%、28%.结论 对于有内科禁忌证或由于其他情况不能手术的老年人晚期NSCLC施行3D-CRT是一种比较有效的治疗手段,有助于提高生存率,改善生存质量,减少并发症的发生.     

Comparison of intensity modulated radiotherapy with simultaneous integrated boost (IMRT-SIB) and a 3-dimensional conformal parotid gland-sparing radiotherapy (ConPas 3D-CRT) in treatment of nasopharyngeal carcinoma: a mono-institutional experience

Aim

To compare intensity modulated radiotherapy with simultaneous integrated boost (IMRT-SIB) and a 3-dimensional conformal parotid gland-sparing radiotherapy (ConPas 3D-CRT) in treatment of nasopharyngeal carcinoma with regard to outcomes and dose distribution to the planning target volumes (PTVs) and to the organs at risk (OARs).

Methods

The treatment records of 24 patients with histologically proven carcinoma of the nasopharynx treated with ConPas 3D-CRT or IMRT-SIB technique between May 2009 and December 2016 were assessed.

Results

The mean dose and dose to 50% parotid glands volume as well as the maximal dose to the spinal cord were significantly lower in the IMRT-SIB than in the ConPas 3-CRT group (p < 0.05; p < 0.05; p < 0.01, respectively). IMRT-SIB was also superior in coverage of PTVs. The 3-year overall survival (OS) and disease-free survival (DFS) of patients in the IMRT-SIB and ConPas 3D-CRT groups were 77 and 81% (p = 0.93), 51.9 and 70.7% (p = 0.83), respectively.

Conclusion

IMRT-SIB provided additional spearing to parotid glands and spinal cord in comparison to ConPas 3D-CRT technique but without improvement of OS and DFS.

     

Biokinetics and dosimetry in patients administered with (111)In-DOTA-Tyr(3)-octreotide: implications for internal radiotherapy with (90)Y-DOTATOC.

Recent advances in receptor-mediated tumour imaging have resulted in the development of a new somatostatin analogue, DOTA-dPhe(1)-Tyr(3)-octreotide. This new compound, named DOTATOC, has shown high affinity for somatostatin receptors, ease of labelling and stability with yttrium-90 and favourable biodistribution in animal models. The aim of this work was to evaluate the biodistribution and dosimetry of DOTATOC radiolabelled with indium-111, in anticipation of therapy trials with (90)Y-DOTATOC in patients. Eighteen patients were injected with DOTATOC (10 microg), labelled with 150-185 MBq of (111)In. Blood and urine samples were collected throughout the duration of the study (0-2 days). Planar and single-photon emission tomography images were acquired at 0.5, 3-4, 24 and 48 h and time-activity curves were obtained for organs and tumours. A compartmental model was used to determine the kinetic parameters for each organ. Dose calculations were performed according to the MIRD formalism. Specific activities of >37 GBq/ micromol were routinely achieved. Patients showed no acute or delayed adverse reactions. The residence time for (111)In-DOTATOC in blood was 0.9+/-0.4 h. The injected activity excreted in the urine in the first 24 h was 73%+/-11%. The agent localized primarily in spleen, kidneys and liver. The residence times in source organs were: 2.2+/-1.8 h in spleen, 1.7+/-1.2 h in kidneys, 2.4+/-1.9 h in liver, 1.5+/-0.3 h in urinary bladder and 9. 4+/-5.5 h in the remainder of the body; the mean residence time in tumour was 0.47 h (range: 0.03-6.50 h). Based on our findings, the predicted absorbed doses for (90)Y-DOTATOC would be 7.6+/-6.3 (spleen), 3.3+/-2.2 (kidneys), 0.7+/-0.6 (liver), 2.2+/-0.3 (bladder), 0.03+/-0.01 (red marrow) and 10.1 (range: 1.4-31.0) (tumour) mGy/MBq. These results indicate that high activities of (90)Y-DOTATOC can be administered with low risk of myelotoxicity, although with potentially high radiation doses to the spleen and kidneys. Tumour doses were high enough in most cases to make it likely that the desired therapeutic response desired would be obtained.     

Dosimetric difference amongst 3 techniques: TomoTherapy,sliding-window intensity-modulated radiotherapy (IMRT), and RapidArc radiotherapy in the treatment of late-stage nasopharyngeal carcinoma (NPC)

To investigate the dosimetric difference amongst TomoTherapy, sliding-window intensity-modulated radiotherapy (IMRT), and RapidArc radiotherapy in the treatment of late-stage nasopharyngeal carcinoma (NPC). Ten patients with late-stage (Stage III or IV) NPC treated with TomoTherapy or IMRT were selected for the study. Treatment plans with these 3 techniques were devised according to departmental protocol. Dosimetric parameters for organ at risk and treatment targets were compared between TomoTherapy and IMRT, TomoTherapy and RapidArc, and IMRT and RapidArc. Comparison amongst the techniques was done by statistical tests on the dosimetric parameters, total monitor unit (MU), and expected delivery time. All 3 techniques achieved similar target dose coverage. TomoTherapy achieved significantly lower doses in lens and mandible amongst the techniques. It also achieved significantly better dose conformity to the treatment targets. RapidArc achieved significantly lower dose to the eye and normal tissue, lower total MU, and less delivery time. The dosimetric advantages of the 3 techniques were identified in the treatment of late-stage NPC. This may serve as a guideline for selection of the proper technique for different clinical cases.     

Mammographic and ultrasonographic comparison between intraoperative radiotherapy (IORT) and conventional external radiotherapy (RT) in limited-stage breast cancer, conservatively treated

OBJECTIVE: Assess mammographic and echographic modifications in mild cases of breast cancer (suitable for conservative surgery) after intraoperatory radio treatment (IORT) as opposed to conventional post-operative radiotherapy (RT). MATERIALS AND METHODS: We report data from 45 patients in each group (IORT and RT). All patients were examined using the same mammographic and ecographic equipment at 6, 12 and 24 months after treatment. We focused on structural alterations, edema and others, and quantified them using pre-established (unbiased) protocols. Both patient examination and subsequent assessment of the results were performed by radiologists with exepertise in breast cancer evaluation. RESULTS: At 6 months, IORT patients showed slightly more pronounced structural distortions and oedema than RT patients; these differences became more apparent at 12 months, with the addition of fat necrosis and/or calcifications. These alterations were evident and consistent under both mammographic and ecographic examination, and became even more pronounced at 24 months. At this stage, RT patients showed minimal alterations of the tissue (apart from normal post-surgical scarring), whereas IORT patients showed virtually no improvement over the preceding 12-month period. CONCLUSION: We show radiological alterations in post-operative breast cancer are significantly more pronounced in patients treated with IORT as opposed to RT.