Microsoft Word - PPt Prajnan Das - Treatment Modalities Radiation Therapy - Mandarin Chinese.doc

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1 PowerPoint Slides English Text Mandarin Chinese Translation 治疗方法 : 放射治疗 VideoTranscript 视频文本 Professional Oncology Education Time: 23:50 Prajnan Das, M.D., M.P.H. Assistant Professor Radiation Oncology The University of Texas MD Anderson Cancer Center Hello, I am Prajnan Das, Faculty Member in the Department of Radiation Oncology at The University of Texas MD Anderson Cancer Center. We are going to talk today about some of the basic principles regarding radiation therapy. 专业人员肿瘤教学讲座 治疗方法 : 放射治疗 时间 : 23:50 德克萨斯大学 MD Anderson 癌症中心 放射肿瘤科 助理教授 Prajnan Das, M.D., M.P.H. 大家好, 我叫 Prajnan Das, 是德克萨斯大学 MD Anderson 癌症中心放射肿瘤科的助理教授 我们今 天的讲座内容是关于放射疗法的一些基本原则 Prajnan Das, M.D., M.P.H. Assistant Professor Radiation Oncology 1

2 Objectives Upon completion of this lesson, participants will be able to: Understand the biologic effects of radiation Understand the steps involved in radiation therapy planning Identify selected clinical applications and complications associated with radiation therapy We will talk about the biologic effects of radiation, how radiation works. We will discuss the steps involving radiation therapy planning, and we will talk about some clinical applications and complications associated with radiation therapy. 我们会谈谈放射的生物作用, 放射的起效方式 我们 会讨论规划放射疗法的步骤, 还会介绍放射疗法的一 些临床应用和相关并发症 First, how does radiation work? 首先, 放射是如何起效的呢? How Does Radiation Work? 2

3 Types of Radiation Non-ionizing Do not produce ions in matter Microwaves, ultrasound, radio waves Ionizing Eject orbital electrons and produce ions Directly ionizing Charged particles (electrons, protons, alpha particles) Indirectly ionizing Uncharged particles (neutrons, gamma rays, x-rays) Effects of Ionizing Radiation Radiation There are two kinds of radiation non-ionizing and ionizing. Non-ionizing radiation consists of particles that do not have enough energy to produce ions in matter, such as microwaves, ultrasound, and radio waves. Since these kinds of radiation do not produce ions in matter, their biologic effects can be limited. In contrast, ionizing radiation is able to eject orbital electrons and produce ions. There are two kinds of ionizing radiation. Directly ionizing, these are charged particles, such as electrons, protons, and alpha particles; and indirectly ionizing, and these are uncharged particles, such as neutrons, gamma rays, and x-rays. Ionizing radiation leads to ionizations. The ionizations then go on to produce free radicals in tissue and the free radicals cause DNA damage, and the DNA damage leads to the biologic effects of ionizing radiation. 有两种放射 非电离放射和电离放射 非电离放射含有的粒子能量不足, 不能在物质中产生离子, 例如微波 超声波和无线电波 因为这些类型的放射不在物质中产生离子, 因此其生物作用有限 与之相反, 电离放射能够发射出轨道电子, 并产生离子 电离放射有两种 一种是直接电离 这些是带电粒子, 例如电子 质子和 α- 粒子 另一种是间接电离 这些是不带电的粒子, 例如中子 伽马射线和 X 光 电离放射会产生电离 电离会在组织中产生游离基, 而这些游离基会损伤 DNA, 进而引发电离放射的生物作用 Ionizations Free Radicals DNA Damage Biologic Effects 3

4 Radiation and DNA Free radicals produce DNA strand breaks Single strand breaks are repaired easily Double strand breaks difficult to repair Most important lesion produced by radiation Can lead to cell death, mutation or carcinogenesis Affects tumor and normal tissue How does radiation damage DNA? The free radicals can produce strand breaks in the DNA. When strand breaks are produced in a single strand of DNA, the single strand breaks can be repaired easily. But when strand breaks are produced in both strands, these double strand breaks can be difficult to repair. Hence double strand breaks are the most important lesion produced by radiation. Double strand breaks can lead to cell death, mutation, or carcinogenesis. And these double strand breaks can affect both tumor and normal tissue. 放射是如何损伤 DNA 的呢? 游离基可导致 DNA 链断裂 如果是单链 DNA 断裂, 则修复容易 但如果是双链断裂, 则难以修复 所以说, 双链断裂是放射引起的最重要病变 双链断裂可导致细胞死亡 突变和致癌 而且双链断裂可影响肿瘤和正常组织 Therapeutic Goals Maximize damage to tumor cells Minimize damage to normal tissues Since radiation can affect both tumor and normal tissue, the goal of a radiation oncologist is to maximize damage to the tumor cells, but minimize damage to normal tissues. 由于放射可以影响肿瘤和正常组织, 所以放射肿瘤科 医生的目标是尽可能破坏肿瘤细胞, 同时将对正常组 织的损伤降到最低 4

5 Radiation Dose Measured in terms of energy imparted by ionizing radiation per unit mass of matter 1 Gray (Gy) = 1 Joule/kg 1 Gy = 100 cgy The way we measure radiation dose is in terms of energy imparted by ionizing radiation per unit mass of matter. The unit of radiation is a Gray (Gy), and a Gray is one Joule of radiation delivered per kilogram of matter. Another commonly used unit is a centigray (cgy) and 1 Gy equals 100 cgy. 我们用每单位物质电离放射产生的能量来衡量放射剂量 放射的单位是戈瑞 (Gy) 一戈瑞等于向每千克物质提供的一焦耳放射量 另一个常用单位是厘戈瑞 1 戈瑞等于 100 厘戈瑞 Fractionation Dividing dose into a number of fractions 4R s: repair of DNA damage, repopulation of cells, reassortment in the cell cycle, reoxygenation A lower total dose in large fractions can have the same biologic effect as a higher total dose in small fractions Single vs. multiple fractions/day can have different effects Radiation is often not given in a single dose but given in a number of smaller doses spread over several days. This process of dividing the radiation dose into a number of smaller doses or fractions is known as fractionation. The biologic basis of fractionation are the four R s : repair of DNA damage, repopulation of cells, reassortment into cell cycle and reoxygenation. And these biologic processes affect the effect of radiation when it is given over several fractions. For example, a lower total dose in large fractions can have the same biologic effect as a higher total dose given in small fractions over a longer time period. Similarly, single fractions of radiation can have completely different effects compared to multiple fractions given daily. 放射通常不是一次给予全量, 而是在数天时间内, 分成几次较小的剂量给予 这种将放射剂量分成一系列较小的剂量或分成数次的做法被称为分剂 分剂的生物学原理是四个 R 修复(Repair) DNA 损伤 细胞再增生 (Repopulation) 细胞周期的再分布 (Reassortment) 和复氧 (Reoxygenation) 分数次给予放射时, 这些生物学过程会影响放射的效果 例如, 总剂量较低而分剂量较大可以取得与总剂量较高 分剂量较小 持续时间较长同样的生物作用 同样, 与每日给予数次分剂相比, 单次分剂放射可以获得完全不同的效果 5

6 Factors Affecting Biologic Effects of Radiation Type of radiation Depends on the density of ionizations produced by radiation Dose rate Type of tissue Early responding vs. late responding tissues Oxygenation Radiosensitization Chemotherapy (5-FU, cisplatin) and biologics (cetuximab) Overall treatment time There are a number of factors that can affect the biologic effects of radiation. The type of radiation is important, and this can depend on the density of ionizations produced by that kind of radiation. The dose rate of radiation is important, whether you are giving radiation at a slower rate or at a faster rate. The type of tissue is important. In general, you can divide tissues into early responding tissues and late responding tissues. Early responding tissues typically include rapidly proliferating cells, such as skin and gastrointestinal mucosa. And these tend to be more sensitive to radiation and also exhibit damage from radiation early in the time course. Late responding tissues typically include cells that do not proliferate at a fast rate, such as neurons or renal cells. And these tend to be more resistant to radiation and exhibit damage from radiation at a later point in time. As we discussed earlier, for DNA damage to take place from radiation, you need free radicals, and free radical production requires oxygen. Hence, the level of oxygenation in a tissue can affect the role of radiation. And hypoxic cells tend to be less sensitive to radiation. A number of agents can be used for radiosensitization, such as chemotherapeutic agents, 5-FU, cisplatin, and biologic agents such as cetuximab. And these have been shown to enhance the effects of radiation in randomized trials. The overall treatment time is also important. Hence, if gaps are introduced in the middle of a patient s radiation therapy course, the therapeutic effects of radiation may be diminished. 有一些因素会影响放射的生物作用 放射种类很重 要, 这取决于放射种类产生的电离密度 放射的剂量 速度也很重要, 这是指给予放射的速度较慢还是较 快 组织类型也很重要 一般来说, 可以将组织分为早期反应组织和晚期反应组织 早期反应组织一般包 括快速增生的细胞, 例如皮肤和胃肠道黏膜 这些组织对放射更为敏感, 会在放疗早期出现损伤 晚期反 应组织一般包括不会快速增生的细胞, 例如神经元或肾细胞 这些组织对放射的抵抗力更强, 会在放疗较 晚期出现损伤 正如我们前面讨论的一样, 放射要损 伤 DNA 需要有游离基, 而游离基的产生需要氧气 因此, 组织内的氧合水平会影响放射的作用 乏氧细 胞对放射较不敏感 可以使用一些药剂来起到放射致敏的作用, 例如化疗制剂 5-FU 顺铂和诸如西妥 昔单抗在内的生物制剂 随机化试验已经显示这些放 射致敏制剂可以加强放疗的效果 总体治疗时间也很 重要 因此, 如果在患者的放射疗程期间出现间断, 则放射的疗效可能会减弱 6

7 So far, we have been talking about how radiation works. Next, we are going to be talking about how radiation is given. 我们已经讨论了放射的起效方式 接下来我们会介绍 放射的给予方式 How is Radiation Given? Simulation Position patient Immobilization with masks, body cradles Image patient Fluoroscopy CT scan Newer techniques: image fusion, 4-D CT Reference marks Ink marks, tattoos The first step in the radiation planning process is simulation. For radiation simulation, the patient has to be positioned. We have to decide whether to position the patient prone or supine, what position the arms or legs have to be in. And the patient then gets immobilized with devices, such as thermoplastic masks for the head and neck, cradles for the body, and these allow us to place the patient in the same position every day in a reliable and reproducible manner. Once the patient is positioned, the patient gets imaged. In the past, fluoroscopy was used, but this has largely been replaced by CT scans now. The photo here shows an example of a CT scan used for radiation simulation. A number of newer techniques have been introduced in the simulation process. Image fusion can be used to fuse head images and MR images with CT images so that the target can be delineated more accurately. 4-D CT images can be used to track motion of a tumor and normal structures over time while the patient breathes. And 放射规划过程的第一步是模拟 在放射模拟期间, 患者必须定位 我们必须决定患者是采用仰卧位还是俯卧位, 手臂或腿部的位置如何 接下来使用器具固定患者 例如使用热塑面罩固定头颈部, 使用托架固定身体 这样就能够以可靠并且可复制的方式, 让患者每天采用相同的体位 一旦定位患者, 就可以对患者进行成像 过去是使用荧光, 但现在大多数情况都转为使用 CT 扫描 这张图片显示的是一台用于放射模拟的 CT 扫描仪 模拟过程出现了一些新技术 图像融合技术用于融合头部图像, 并且将 MR 图像与 CT 图像融合 这样, 就可以更为准确地勾画目标部位的轮廓 4-D CT 图像可以在患者呼吸的同时, 随时追踪肿瘤和正常组织的运动 这一功能对于肝 肺等随 7

8 Treatment Planning Contour radiation targets, other organs Design beam arrangement Number, size, orientation Design blocks to protect normal structures Cerrobend, multi-leaf collimators (MLC) this can be important for organs such as the lungs and the liver which move when a patient breathes. Once a patient is positioned and imaged, reference marks are placed on the patient using ink marks or tattoos, and the patient can be lined up to these every day for treatment. The next step in the radiation planning process is treatment planning. This involves the radiation oncologist going through the CT images slice by slice and outlining the radiation targets and other organs on every slice. This process is called contouring. Once the targets are delineated through the contouring process, we have to design the beam arrangement. We have to decide how many beams we will use, what size the beams are going to be, and what their orientation or angles are going to be. Then each beam can be shaped using blocks so that the target is treated, but normal structures are protected. Blocks can be made with a leadcontaining material called Cerrobend. Nowadays, fields are typically blocked using multi-leaf collimators which are thick leaves in the head of a radiation treatment machine that can move in and out of the field, thus shaping the field. 呼吸移动的器官非常重要 一旦患者完成了定位和成像, 使用墨水记号或纹身贴纸在患者身上做参考标记, 这样患者就可以每天按照这些标记定位, 接受治 疗 放射规划过程的下一步是治疗规划 这需要放射肿瘤科医生逐张查看 CT 图像层, 在每层上勾勒出放射目标部位和其他器官的轮廓 这一过程成为勾画轮廓线 一旦通过勾画轮廓线过程绘制了目标部位的轮廓, 则必须设计安排光束 必须决定使用多少光束, 光束的大小以及方向或角度, 每个光束通过铅块来定形, 这样就可以治疗目标部位, 同时让正常部位得到 保护 可以用一种名为 Cerrobend 的含铅材料制作铅块 现在通常采用多叶准直器来遮挡放射野 多叶准直器是在放射治疗仪头部的厚叶片, 通过进出放射 野来适形放射野 8

9 Treatment Machines Cobalt-60 Linear accelerators Photons Electrons Case Study 66 year old man, resectable pancreatic cancer Plan: Pre-op chemo-rt Surgery CT simulation Supine, arms up, body cradle Contouring Tumor, LN, kidneys, liver, spinal cord 4-field technique Once a patient goes through simulation and treatment planning, we are now ready to treat the patient. A variety of treatment machines can be used. In the past, radiation was most commonly delivered using Cobalt-60, which is an isotope that generates radiation. Cobalt-60 is still widely used in developing countries. In the developed world, Cobalt-60 is commonly used in gamma ray machines for stereotactic treatments. However, the most common method of delivering external beam radiation therapy is by using linear accelerators. The photo here shows an example of a linear accelerator used to deliver radiation therapy. Linear accelerators can generate two different kinds of radiation, photons and electrons, and these have different clinical applications. Next, we will go through a case study that illustrates the steps of radiation planning that we have been talking about. The patient here is a 66-year-old man who had resectable pancreatic cancer. After multidisciplinary discussion, we recommended preoperative chemoradiation followed by surgery. We used a CT-based simulation technique. The patient was placed in a supine position with his arms up. A body cradle was used for immobilization, and then CT images of the abdomen were obtained. We then went through the CT images slice-by-slice and outlined the tumor, surrounding lymph nodes regions, and normal structures, such as the kidneys, liver and spinal cord. We decided to treat this patient with a 4-field technique: anterior, posterior, and two lateral fields. 一旦患者完成模拟和治疗规划, 就可以对患者进行治疗了 可以使用各种治疗仪 过去最常使用钴 60 来提供放射 钴 60 是一种同位素, 可以产生射线 现在发展中国家仍然广泛使用钴 60 在发达国家, 钴 60 通常用在伽马射线仪上, 用于进行立体定向治 疗 而提供外放射治疗的最常见方法是使用线性加速器 这张照片显示了用于提供放射治疗的一例线性加 速器 线性加速器可以产生两种不同类型的射线, 光 子和电子, 两者有不同的临床应用 接下来我们会通过一个病例来演示我们讨论的放射规划步骤 患者是一名 66 岁男性, 患有可切除的胰腺癌 经过多学科讨论之后, 我们建议先接受术前化放疗再接受手术 我们使用了 CT 模拟技术 患者采用 仰卧位, 双臂上举 使用身体托架进行固定, 然后取得了腹部的 CT 图像 我们接下来逐层查看 CT 图像, 勾绘出肿瘤 周围淋巴结区域和诸如肾 肝和脊髓的正常组织轮廓 我们决定以 4 野技术治疗这位患者 : 前野 后野以及两个侧野 9

10 Fields The figure on the left shows the anterior field and the figure on the right shows the lateral field used to treat this patient. The large red structure in the middle of the field shows the pancreatic tumor. The other colored structures show other lymph node regions that were included in the target. The red and blue boxes show the actual radiation fields, and the white stripes show the multi-leaf collimators that were used to block parts of the field and shape the field. 左侧图像显示了治疗该患者的前野, 右侧图像显示了 治疗的侧野 放射野中部的大块红色结构是胰腺肿瘤 其他颜色组织显示的是包括目标部位在内的其他淋巴结区域 红色和蓝色方框显示了实际的放射野, 白色条纹显示的是用于遮挡放射野其他部分并适形放 射野的多叶准直器 AP LAT Isodose Plan Once the fields are designed, we can evaluate the radiation plan using isodose curves. We obtain isodose curves for each slice of the CT scan and want representative slices shown here. Each isodose line represents a particular dose of radiation therapy. In this case, the prescription dose was 5040 cgy as shown by the white line. As you can see, the tumor is being adequately covered by the white line. In contrast, normal structures, such as the bowel, liver, and kidneys, are getting much lower doses of radiation. 一旦确定了放射野, 则可以使用等剂量曲线评估放射 计划 我们获得 CT 扫描每一层的等剂量曲线, 并在 这里显示具有代表性的各层 每条等剂量线代表了放 射治疗的一个特定剂量 在这个病例中, 处方剂量是 5040 厘戈瑞, 用白线表示 大家可以看到, 白线足以覆盖肿瘤 而正常组织, 例如肠 肝脏和肾脏所受 的放射量要少很多 10

11 DVH IMRT Intensity modulated radiation therapy Computer aided optimization Multiple beams, multi-leaf collimation Highly conformal RT to targets Minimizes dose to normal tissues Dose painting of targets You can quantify doses received by the target and normal structures using a DVH or Dose Volume Histogram. In this figure, the x-axis shows the radiation dose, and the y-axis shows the proportion of each organ that is receiving that dose. As you can see from the green line on the top, the tumor and the targeted lymph nodes, 100% of those are getting the prescribed dose of 5040 cgy. The dose to the spinal cord is shown in red. The maximum dose the spinal cord can tolerate is 45 Gy. As you can see, no part of the spinal cord is getting more than 30 Gy. The orange line shows dose to the liver. The tolerance dose for the liver is 30 Gy. As you can see, less than 10% of the liver is getting more than 30 Gy. Similarly, the kidneys are also within the acceptable tolerance limits. Radiation therapy can also be delivered using IMRT which stands for Intensity Modulated Radiation Therapy. IMRT uses computers to optimize the radiation plan. Multiple beams are used, and these beams are shaped with multi-leaf collimation in complex patterns. This allows us to deliver highly conformal radiation therapy to the target, but minimize dose to surrounding normal tissues. IMRT also allows dose painting so that different areas of a target can be treated with different prescribed doses. 可以通过 DVH, 即剂量体积直方图, 来对目标部位和正常组织接受的剂量进行定量 此图的 X 轴代表放射剂量,Y 轴代表各器官接受该剂量的比例 从顶 部的绿线可以看出, 肿瘤和目标淋巴结能够 100% 得到 5040 厘戈瑞的处方剂量 脊髓得到的剂量以红色 显示 脊髓能够耐受的最大剂量是 45 戈瑞 大家可 以看到, 没有任何部分的脊髓受到了 30 戈瑞以上的 放射 橙线显示了肝脏接受的剂量 肝脏的耐受剂量是 30 戈瑞 可以看出, 受到 30 戈瑞以上的肝脏部 位不到肝脏的 10% 与此类似, 肾脏获得的放射也 在可以接受的耐受限值之内 也可以使用 IMRT, 即强度调控放射治疗来给予放 疗 IMRT 使用计算机来对放射计划进行优化 使用多光束, 而且在复杂模式下会使用多叶准直来对这些光束进行适形 这就允许我们向目标部位提供高度适 形的放射治疗, 同时将周围正常组织受到的放射剂量 降到最低 使用 IMRT 还可以进行剂量调饰, 从而在 目标部位的不同区域使用不同的处方剂量进行治疗 11

12 IMRT Beams As I mentioned, IMRT uses multiple beams shaped in complex manners as shown by these radiographs. 我前面曾提到,IMRT 可以对多波束进行复杂适形, 如这些 X 光片所示 IMRT for Anal Cancer This is an example of a patient treated with IMRT for squamous cell anal cancer. The red structure represents the primary tumor which is being treated to a dose of 54 Gy as shown by the red line. An involved lymph node is shown by the blue structure which is being treated with a dose of 50 Gy as shown by the blue line. Other lymph node regions shown by the green --- shown in green are being treated with a dose of 45 Gy as shown by the green line. Note that the radiation dose lines are bending away from critical structures, such as the bowel, genitalia, and femoral heads. Thus, IMRT allows us to treat the target but spare normal tissues in a manner that cannot be always achieved using conventional treatment plans. 这是一个用 IMRT 治疗患者鳞状细胞肛门癌的例子 红色组织代表原发肿瘤, 用剂量 54 戈瑞治疗, 如红线所示 蓝色组织是累及的淋巴结, 用剂量 50 戈瑞 治疗, 如蓝线所示 其他淋巴结区域用绿色表示, 用 剂量 45 戈瑞治疗, 如绿线所示 请注意, 放射剂量线偏离重要结构, 例如肠 生殖器和股骨头 因此, 使用 IMRT 可以治疗目标部位, 并且使正常组织免于 接受放射, 而传统治疗方案并非总能做到这一点 12

13 Proton Therapy Special physical properties Deposit dose within a short distance (Bragg peak) Minimal dose beyond Bragg peak Another exciting innovation in the field of radiation therapy is proton therapy. Protons are charged particles with special physical properties that are different from that of photons, which is what we typically use in using our linear accelerators. In the figure, the x-axis shows the depth from the surface into the body of a patient, and the y-axis shows relative radiation dose. The green line shows dose distribution from a 15 megavoltage photon beam. As you can see, near the skin surface there is some sparing, but then the dose peaks and then falls gradually. So if you needed to treat a tumor, say at a depth of 20 cm, regions that are right behind it and right ahead of it would get similar doses of radiation. In contrast, a proton beam behaves very differently as shown by the red line. As you can see, there is a certain entrance dose, but then the dose rises up very rapidly and dose gets deposited within a short distance known as the Bragg peak. Beyond the Bragg peak, the dose falls off abruptly and there is minimal dose beyond the Bragg peak. This allows us to treat an organ while delivering minimal dose to surrounding normal structures. 放射治疗领域另一项激动人心的创新是质子治疗 质 子是有着特殊物理特性的带电粒子 质子与一般用于线性加速器的光子不同 这张图的 X 轴线表示从患 者体表到体内的距离,Y 轴表示相对放射剂量 绿线表示一个 15 兆伏光子束的剂量分布 大家可以看到, 在接近皮肤表面处有一些的免受放射作用, 然后剂量达到峰值, 接着逐渐下降 所以如果需要治疗, 比如说位于皮下 20 厘米的肿瘤, 则其正下方和正上 方的区域会得到类似的放射剂量 相反, 红线显示的 质子束表现极为不同 大家可以看到有一定的入射剂 量 但是接着剂量急剧升高, 在较短距离内剂量达到顶峰, 称为布拉格峰 布拉格峰之后, 剂量急速下 降 布拉格峰之后的剂量极低 这样我们就可以治疗某个器官, 而使周围正常组织受到最小剂量 13

14 Brachytherapy Brachy: Short distance Radioactive material placed within the body Dose decreases rapidly with distance from the radioactive material Most of the examples of radiation that we have talked about so far involve teletherapy or external beam radiation therapy. Another way of delivering radiation therapy is brachytherapy. Brachy means short distance. In brachytherapy, the radioactive material, radioisotopes, are placed within the body, either within a body cavity or within the tissues. The radiation dose decreases rapidly with distance from the radioactive material, and this allows us to treat the tumor to a high dose, but spare surrounding normal structures. The radiograph here shows an example of a prostate cancer patient treated with brachytherapy. The little gray specks within the prostate show individual radiation seeds that were placed into the prostate to treat this patient. In the last section, we are going to discuss some clinical issues pertinent to radiation therapy. 到目前为止我们讨论的放射示例都属于远距治疗或外 放射治疗 提供放射治疗的另一种方式是近接治疗 近接是指短距离 在近接治疗中, 将放射活性物质, 即放射同位素放入身体的体腔内或组织内 随着离放射活性物质的距离增加, 放射剂量急剧下降 这样就 能用高剂量治疗肿瘤, 而使周围正常结构免受高剂量放射 这张 X 光片显示的病例是接受近接治疗的一位前列腺癌患者 前列腺内的灰色颗粒是放入前列腺 内 对患者进行治疗的各个放射粒子 在最后一部分, 我们将讨论一些与放射治疗有关的临 床问题 Clinical Issues 14

15 Roles of Primary treatment/definitive Prostate, lung, head and neck, cervix, anal canal Post-operative Breast, stomach Pre-operative Rectum, esophagus Consolidative after chemo Lymphoma Palliative Radiation therapy can have a variety of roles in the care of a cancer patient. Radiation therapy can be used for primary treatment in the definitive setting, such as for prostate cancer, lung cancer, head and neck cancer, cervical cancer, and anal canal cancer. And for many of these cancers, radiation is given concurrently with chemotherapy. Radiation therapy can be used for post-operative treatment for breast cancer and stomach cancer, for preoperative treatment of rectal and esophageal cancer. Radiation therapy is used for consolidation after chemotherapy for many lymphomas. And radiation can also be used for palliation of symptoms. 在对癌症患者的护理中, 放射治疗可以起到各种不同的作用 在特定情况下, 放射治疗可用作主要治疗方 法, 例如用于治疗前列腺癌 肺癌 头颈癌 宫颈癌 和肛管癌 对于这些癌症中的许多类型, 放疗与化疗 合并使用 放射治疗可用于乳腺癌和胃癌的术后治 疗, 用于直肠癌和食道癌的术前治疗 放射治疗可在 许多淋巴瘤接受化学治疗之后作为巩固治疗 放射治 疗还可用于症状的姑息治疗 Indications for Urgent RT Spinal cord compression Brain metastasis with symptoms Superior Vena Cava (SVC) syndrome with progression Uncontrolled bleeding Peripheral nerves with symptoms It is important to keep in mind that there are certain indications for urgent radiation therapy, and these patients need to be referred to a radiation oncologist on an emergent basis. Examples include spinal cord compression, brain metastasis with symptoms, SVC syndrome with progressive symptoms, uncontrolled bleeding, or peripheral nerve involvement with symptoms. 需要牢记一些需要紧急放射治疗的指征, 并且将这样的患者紧急转诊给放射肿瘤科医生 相关例子包括脊髓压迫 有症状的脑转移 症状恶化的上腔静脉综合 症 未得到控制的出血或者有症状的外周神经累及 15

16 Complications from RT Complications mainly occur locally, in organs that are in the RT field Some complications occur during treatment or within days or weeks Some complications appear after months or years Radiation can cause a variety of complications or side effects. These complications mainly occur locally in organs that are in the radiation field. Some complications can occur during treatment or within days or weeks while some complications can be long term and can appear after months or years. 放射可引起各种并发症或副作用 这些并发症主要见于放射野内的局部器官 一些并发症可在治疗期间, 或者治疗后数日或数周内发生, 而其他一些并发症可以长期存在, 可以在数月或数年后才出现 Examples of Complications Fatigue Skin: erythema, desquamation CNS: somnolence, cognitive loss Head and Neck: mucositis, xerostomia Lung: pneumonitis Upper GI: nausea, esophagitis Lower GI: diarrhea, proctitis GU: cystitis, urethritis Hem: myelosuppression Cardiovascular toxicity Second malignancies Examples of complications include fatigue, skin toxicity such as erythema and desquamation. Radiation to the brain can lead to somnolence or cognitive loss. That to the head and neck area could potentially lead to mucositis and xerostomia. Radiation to the lung can cause pneumonitis; to the upper GI can lead to nausea and esophagitis; and to the lower GI can lead to diarrhea and proctitis. Radiation therapy to the genitourinary system can cause cystitis, urethritis or sexual dysfunction. Radiation can also cause myelosuppression. Two of the most important long-term side effects of radiation include cardiovascular toxicity and second malignancies. 并发症包括疲乏 皮肤毒性, 例如红斑和脱屑 对大 脑进行放射可引起嗜睡或认知能力丧失 对头颈部进 行放射可能会引起黏膜炎和口干症 对肺进行放射可造成肺炎 ; 对上呼吸道进行放射可引起恶心和食道炎, 对下呼吸道进行放射可造成腹泻和直肠炎 对生 殖泌尿系统进行放射可导致膀胱炎 尿道炎或性功能 障碍 放射还可引起骨髓抑制 放射最重要的两项长 期副作用包括心血管毒性和第二恶性疾病 16

17 Role of the Radiation Oncologist Evaluates whether patient is appropriate for RT Integral part of multidisciplinary team Plans and delivers radiation therapy Aided by physicists, dosimetrists, therapists Treats symptoms and side-effects Monitors for relapses and long-term toxicity Specialized procedures Brachytherapy, Intraoperative radiotherapy Conclusions Radiation is an important treatment modality for the management of cancer Treatment planning includes simulation, contouring targets and designing beam arrangements Specialized radiation techniques include intensity modulated radiation therapy, proton therapy and brachytherapy What is the role of a radiation oncologist? A radiation oncologist evaluates whether a particular patient is appropriate for radiation. And in doing so, the radiation oncologist functions as an integral part of the multidisciplinary oncology team. Next, the radiation oncologist plans and delivers radiation therapy. This is a team effort and the radiation oncologist is aided by physicists, dosimetrists, and radiation therapists. Radiation oncologists help treat symptoms and side effects of radiation and also monitors these patients in the long term for relapses and long-term toxicity. Finally, the radiation oncologist performs specialized procedures, such as brachytherapy and intraoperative radiation therapy. In conclusion, we have discussed today that radiation has an --- is an important treatment modality for the management of cancer. The treatment planning process includes simulation, contouring targets, and designing beam arrangements. Specialized radiation techniques include Intensity Modulated, Proton Therapy, and Brachytherapy. We have also discussed some clinical issues relevant to radiation therapy. Thank you for your attention. 放射肿瘤科医生应发挥怎样的作用? 放射肿瘤科医生 评估特定患者是否适合接受放射治疗 这样, 放射肿 瘤科医生就成为多学科肿瘤团队不可或缺的一部分 然后, 放射肿瘤科医生规划和提供放射治疗 这项工 作需要团队协作, 放射肿瘤科医生需要医生 放射剂 量测定师和放射治疗师的协助 放射肿瘤科医生帮助治疗症状和放射的副作用, 还可以长期监测患者, 观察是否有复发和长期毒性 最后, 放射肿瘤科医生还执行专门的程序, 例如近接治疗和术中放射治疗 总而言之, 我们今天讨论了放射是癌症管理的重要治疗方法 治疗规划过程包括模拟 勾绘目标部位的轮 廓和设计安排光束 专门的放射技术包括强度调控放 射治疗 质子治疗和近接治疗 我们还讨论了一些与放射治疗有关的临床问题 感谢各位的参与! 17