小肠勾画方式对胰腺癌放疗计划剂量评估的影响

目的 在晚期胰腺癌放疗计划评估中,比较2种勾画方式对小肠剂量体积限值的影响.方法 对30例晚期胰腺癌患者,采用Small Bowel和Peritoneal Space方式分别勾画小肠,利用剂量体积直方图对小肠受到同一剂量照射体积(V5～ V50)进行分析,同时将小肠受照体积为2 cm3、1 cm3、0.1 cm3的剂量作为最大剂量DMAX(DMAX2,DMAX1,DMAX0.1)进行对比分析.结果 Small Bowel和Peritoneal Space方式勾画的小肠接受同一剂量照射体积(V5～ V50)及最大剂量DMAX2、DMAX1、DMAX0.1比较差异均有统计学意义(均P＜0.05).2种勾画方式小肠V5～ V50均具有相关性(均P ＜0.05),而最大剂量DMAx2、DMAX1、DMAX0.1无相关性(均P＞0.05).结论 Small Bowel和PeritonealSpace勾画方式对小肠的剂量体积和最大剂量有差异,对晚期胰腺癌放疗计划评估时,2种勾画方式需要给予小肠不同的剂量体积限值.     

M6型射波刀立体定向放疗系统图像引导照射剂量研究

目的：分析M6型射波刀立体定向放疗（stereotactic radiotherapy,SBRT）图像引导系统产生的照射剂量及影响因素，为接受M6型射波刀治疗肿瘤患者额外照射剂量提供参考依据。方法：回顾性分析天津医科大学肿瘤医院2023年1月1日至2023年5月31日216例采用M6型射波刀SBRT的肿瘤患者，将患者按照图像引导方式和肿瘤靶区位置进行分类，分别统计患者肿瘤靶区的照射剂量、治疗分割次数、球管曝光参数、计算球管总曝光次数、累积的照射剂量，得出不同图像引导方式和治疗部位平均曝光次数、平均照射剂量，与患者肿瘤靶区的照射剂量相比较，并勾画ROC曲线取肿瘤体积及BED10的cutoff值进行分层，利用多元线性逐步回归模型分析累积剂量的影响因素。结果：颅骨（6D-skull）追踪方式，椎体（x-sight）追踪方式，同步呼吸（sychrony）追踪方式，金标（fiducial）追踪方式，肺追踪（x-sight lung）肿瘤患者平均曝光次数、平均累积照射剂量（cGy）、累积照射剂量/靶区照射剂量（%）分别为131次、1.6 cGy、0.02%～0.18%;212次、8.0 cGy、0...     

乳腺癌放疗化疗时机顺序

放化疗联合治疗乳腺癌不仅涉及化疗方案、剂量、给药方式和放疗剂量、方式、方法等问题,两者时机顺序的合理安排更是获得最佳疗效的关键。现就有关研究进展作一综述。     

恶性肿瘤治疗中放化疗应用的时机和顺序

放化疗联合治疗恶性肿瘤不仅涉及化疗方案、剂量、给药方式或放疗剂量、方式、方法等问题,两者应用时机顺序的合理安排更是获得最佳疗效关键.本文就有关研究进展作一简要综述.     

EBT剂量胶片测量电子线百分深度剂量的应用研究

目的 研究EBT剂量胶片在临床电子线百分深度剂量(PDD)中的测量方法.方法 采用14.7 cm×5.1 cm的矩形射野,在同一张EBT胶片上进行5阶梯度的剂量刻度.应用上述刻度方法,针对4、6、8、10、12和15 MeV电子线,在小水箱中采用竖直和倾斜5°两种方式测量PDD,并与半导体探头的三维水箱扫描结果以及平行板电离室在小水箱中测量结果进行比较和分析°结果当剂量胶片上端与水面平齐时,EBT测量的PDD曲线与两种探头测量的结果具有较好一致性,并且倾斜和竖直测量两种方式无明显差异.当剂量胶片上端伸出水面时,在竖自测量方式下剂量建成区内测量结果明显低于其他测量结果,而倾斜测量方式下则无明显影响.结论 新的剂量刻度方式快捷可靠,可显著减少剂量胶片用量.在测量电子线PDD时建议将胶片倾斜一定角度进行,以便减小胶片上端与水面不平齐所引起的测量误差.     

EBT剂量胶片测量电子线百分深度剂量的应用研究

目的 研究EBT剂量胶片在临床电子线百分深度剂量(PDD)中的测量方法.方法 采用14.7 cm×5.1 cm的矩形射野,在同一张EBT胶片上进行5阶梯度的剂量刻度.应用上述刻度方法,针对4、6、8、10、12和15 MeV电子线,在小水箱中采用竖直和倾斜5°两种方式测量PDD,并与半导体探头的三维水箱扫描结果以及平行板电离室在小水箱中测量结果进行比较和分析°结果当剂量胶片上端与水面平齐时,EBT测量的PDD曲线与两种探头测量的结果具有较好一致性,并且倾斜和竖直测量两种方式无明显差异.当剂量胶片上端伸出水面时,在竖自测量方式下剂量建成区内测量结果明显低于其他测量结果,而倾斜测量方式下则无明显影响.结论 新的剂量刻度方式快捷可靠,可显著减少剂量胶片用量.在测量电子线PDD时建议将胶片倾斜一定角度进行,以便减小胶片上端与水面不平齐所引起的测量误差.     

放射治疗71例骨转移癌止痛效果分析

目的观察低于常规剂量的2种分割方式治疗骨转移性疼痛的疗效。方法71例恶性肿瘤晚期骨转移患者,总计93处骨转移灶,根据疼痛程度及行动受限程度,采取2种均低于常规剂量的分割方式进行放射治疗,分别为Dm30Gy/10f/2W,Dm30Gy/6f/2W。观察疼痛缓解情况。结果2种分割方式止痛有效率分别为88%、95%。两组间无显著差异性(P>0.05)。与国内多数文献报告的结果接近。结论低于常规剂量的分割方式对转移性骨痛疗效与常规剂量的分割方式的疗效相当,且简便易行。     

EBT剂量胶片测量电子线百分深度剂量的应用研究

目的 研究EBT剂量胶片在临床电子线百分深度剂量(PDD)中的测量方法.方法 采用14.7 cm×5.1 cm的矩形射野,在同一张EBT胶片上进行5阶梯度的剂量刻度.应用上述刻度方法,针对4、6、8、10、12和15 MeV电子线,在小水箱中采用竖直和倾斜5°两种方式测量PDD,并与半导体探头的三维水箱扫描结果以及平行板电离室在小水箱中测量结果进行比较和分析°结果当剂量胶片上端与水面平齐时,EBT测量的PDD曲线与两种探头测量的结果具有较好一致性,并且倾斜和竖直测量两种方式无明显差异.当剂量胶片上端伸出水面时,在竖自测量方式下剂量建成区内测量结果明显低于其他测量结果,而倾斜测量方式下则无明显影响.结论 新的剂量刻度方式快捷可靠,可显著减少剂量胶片用量.在测量电子线PDD时建议将胶片倾斜一定角度进行,以便减小胶片上端与水面不平齐所引起的测量误差.     

ICRU 83号报告推荐方式评估宫颈癌术后辅助IMRT与传统放疗方式的差异及可行性

目的：以国际辐射单位与测量委员会（International Commission on Radiation Units and Measurements, ICRU）83号报告推荐的方式评估调强适形放疗（intensity-modulated radiotherapy,IMRT）方式与传统二维二野等中心放疗方式用于宫颈癌术后辅助放疗的差异及可行性。方法回顾性分析10例宫颈癌术后IMRT和模拟传统二维放疗的剂量体积直方图（dose-volume histogram,DVH）数据。统计计划靶区体积（planning target volume,PTV）、D100、D98、D95、D50、Dmean、D2、D0,计算均匀性指数（homogeneity index,HI）;以D50评估不同放疗方式对剂量的影响;分别统计危及器官（organs at risk,OAR）的DVH参数并进行分析。结果以D50评估IMRT方式的PTV剂量较二维放疗方式提高4.47%±3.62%,其实际差值为（200±157）cGy（t=4.2,P=0.001）。IMRT中骨盆的V10和V20高于二维放疗,V30的差异无统计学意义。IMRT中小肠的V10和V20高于二维放疗,V40低于二维放疗。IMRT中膀胱和直肠的V40、Dmean低于二维放疗,而以D1c、D2c、D2和Dmax为指标评估高剂量区,两种放疗方式的差异无统计学意义。结论 ICRU 83号报告推荐方式适用于IMRT计划评估;IMRT较传统放疗方式提高了靶区剂量,增加了骨盆和小肠的低剂量受照体积,降低了膀胱和直肠的整体受照剂量,但仍存在小体积较高剂量。若采用D50作为评估标准,可考虑降低剂量4.47%±3.62%。     

非小细胞肺癌放射治疗的剂量分割研究进展

放疗是局限晚期非小细胞肺癌患者的主要治疗手段,改变不同的剂量分割方式是提高放疗疗效的手段之一.不同的剂量分割方式有不同的优缺点,当然也适用于不同的患者.我们将对非小细胞肺癌放射治疗不同的剂量分割方式作一综述.     

Bacteria and cancer--antagonisms and benefits

There is considerable historical and recent evidence concerning the antagonisms between acute bacterial infections or their toxins and cancer and allied diseases. These data provide renewed incentives to undertake clinical programmes with mixed bacterial vaccines in many countries at the present time.     

Religiosity and physical and emotional functioning among African American and White colorectal and lung cancer patients

The literature suggests that religiosity helps cope with illness. The present study examined the role of religiosity in functioning among African Americans and Whites with a cancer diagnosis. Patients were recruited from an existing study and mailed a religiosity survey. Participants (N = 269; 36% African American, 56% women) completed the mail survey, and interview data from the larger cohort was utilized in the analysis. Multivariate analyses indicated that in the overall sample religious behaviors were marginally and positively associated with mental health and negatively with depressive symptoms. Among women, religious behaviors were positively associated with mental health and negatively with depressive symptoms. Religiosity was not a predictor of study outcomes for men. Among African Americans, religious behaviors were positively associated with mental health and vitality. Among Whites, religious behaviors were negatively associated with depressive symptoms. These findings suggest a mixed role of religious involvement in cancer outcomes. The current findings may have applied potential in the areas of emotional functioning and depression.     

VEGF及KDR在大肠腺瘤和腺癌中的表达及意义

目的：探讨VEGF和KDR在大肠腺瘤和大肠腺癌中的表达及临床病理特征的关系。方法：大肠腺瘤和大肠腺癌组织标本各100例,采用免疫组织化学染色法检测VEGF和KDR在标本中的表达情况。结果：VEGF和KDR在大肠腺癌组中的阳性表达明显高于大肠腺瘤组（P〈0.05）;在正常大肠黏膜均未见VEGF和KDR表达的阳性染色;VEGF阳性表达组中KDR的阳性表达率为70%,显著高于VEGF阴性表达组中KDR的阳性表达率16%,两组比较有统计学意义（P〈0.01）。结论：大肠腺癌组织中KDR的表达与肿瘤大小、转移情况、浸润深度密切相关;VEGF和KDR在大肠腺瘤中的表达与患者的年龄、性别及分型均无相关性,而与增生程度相关（P〈0.05）。在大肠腺癌患者中VEGF及KDR表达更高,二者具有协同效应。     

Renal irradiation and the pharmacology and toxicity of methotrexate and cisplatinum

We used a rat model to study the effects of renal irradiation on the pharmacology of methotrexate (MTX) and cisplatinum (cis-Pt). Unanesthetized rats were given bilateral kidney irradiation (20 Gy in 9 fractions). At 9 months after irradiation, 3% of the animals had died and survivors showed moderately impaired renal function. At 15 months, 30% of the animals had died and survivors showed severely impaired renal function. Some animals were given i.v. MTX 1 week to 15 months after irradiation. In irradiated rats, the area under the MTX plasma clearance curve equaled that of controls through 6 months, and was significantly above controls from 9 months on. Other animals were given i.p. cis-Pt 1 week to 9 months after irradiation. The acute toxicity of cis-Pt was the same in control and irradiated rats when cis-Pt was given immediately before or after irradiation. Beginning 3 months after irradiation there was a progressive increase in cis-Pt toxicity and a simultaneous decrease in urinary platinum excretion. Irradiated animals that survived cis-Pt treatment showed increased radiation nephritis; the greatest effect occurred when cis-Pt was given 3 months or more after irradiation. MTX and cis-Pt clearance decreased when renal dysfunction was first observed and changes in renal function preceded changes in drug clearance and toxicity.     

Fruit and vegetables and cancer risk

The possibility that fruit and vegetables may help to reduce the risk of cancer has been studied for over 30 years, but no protective effects have been firmly established. For cancers of the upper gastrointestinal tract, epidemiological studies have generally observed that people with a relatively high intake of fruit and vegetables have a moderately reduced risk, but these observations must be interpreted cautiously because of potential confounding by smoking and alcohol. For lung cancer, recent large prospective analyses with detailed adjustment for smoking have not shown a convincing association between fruit and vegetable intake and reduced risk. For other common cancers, including colorectal, breast and prostate cancer, epidemiological studies suggest little or no association between total fruit and vegetable consumption and risk. It is still possible that there are benefits to be identified: there could be benefits in populations with low average intakes of fruit and vegetables, such that those eating moderate amounts have a lower cancer risk than those eating very low amounts, and there could also be effects of particular nutrients in certain fruits and vegetables, as fruit and vegetables have very varied composition. Nutritional principles indicate that healthy diets should include at least moderate amounts of fruit and vegetables, but the available data suggest that general increases in fruit and vegetable intake would not have much effect on cancer rates, at least in well-nourished populations. Current advice in relation to diet and cancer should include the recommendation to consume adequate amounts of fruit and vegetables, but should put most emphasis on the well-established adverse effects of obesity and high alcohol intakes.     

New and emerging radiosensitizers and radioprotectors

The combination of chemotherapy and radiation has led to clinical breakthroughs in several disease sites, and current work continues to define optimum combinations of proven chemotherapy as well as more recently available, noncytotoxic agents. Administration of systemic therapies allows modulation of radiation response to improve tumor control (radiosensitization) or to prevent normal tissue toxicity (radioprotection). Substantial progress has been made in identifying the targets of standard chemotherapeutic radiation sensitizers and protectors as well as in the introduction of a new generation of molecularly targeted therapies in combination with radiation. We have reviewed the most recent, predominantly early phase clinical trials combining systemic agents with radiation. Although the proof of an improved schedule ultimately needs to come from well-run Phase III trials, the search among schedules could be shortened by the use of surrogate endpoints such as presence of active drug metabolites in the tumor. This has been accomplished only in a few cases and needs to become a more standard part of radiation sensitizer and protector trials.