•Radiation modality reflects whether a treatment was external beam, brachytherapy, a radioisotope as well as their major subtypes, or a combination of modalities. This data item should be used to indicate the radiation modality administered during the first phase of radiation.
Full Answer
What are the different therapeutic modalities of radiation therapy?
Therapeutic modalities: radiation therapy 1 Goals of radiation therapy. The goal of definitive or curative radiation therapy is eradication of all viable tumor cells within the patient. 2 Normal tissue response. ... 3 Pre-radiation imaging. ... 4 Tumor-specific radiation considerations. ... 5 Newer technologies. ...
What are the treatment modalities and technologies for cancer?
Treatment modalities and technologies. Radiotherapy can be applied as an indivudual treatment, or in combination with surgery and/or chemotherapy. Radiation damages the DNA of cells in your body. When given a high enough radiation dose, the cells in the tumor will no longer be able to divide and tumor growth will be halted.
What are state of art methods of radiation therapy?
State of art radiation therapy currently includes stereotactic radiosurgery and stereotactic body radiation therapy. These methods involve more sophisticated technology and delivery of single or several fractions of high-dose radiation therapy with a narrow margin.
What is the meaning of “radiotherapy”?
Radiotherapy means “to treat using radiation”. You may be familiar with the use of radiation for making an X-ray image. The same kind of X-rays, with a much higher energy, can also be used to treat harmful parts of the human body such as a tumor.
What is AP PA radiation?
Radiation fields were once as basic as a single treatment field (port) or uncomplicated anterior/posterior opposed (AP/PA) treatment fields with or without simple blocking utilized to shape the treatment beams.
What are the 3 types of radiation treatment?
Three common types of internal radiation therapy include:Brachytherapy involves radioactive material that is implanted in the body. ... Intraoperative radiation therapy (IORT) is used to treat an exposed tumor during cancer surgery. ... Stereotactic radiosurgery (SRS) is not actually surgery.
What is the meaning of radiation therapy?
Radiation therapy (also called radiotherapy) is a cancer treatment that uses high doses of radiation to kill cancer cells and shrink tumors. At low doses, radiation is used in x-rays to see inside your body, as with x-rays of your teeth or broken bones.
What are the four types of radiation therapies?
There are several types of brachytherapy characterized by different methods of placing radiation inside the body: interstitial brachytherapy, intracavitary brachytherapy, intraluminal radiation therapy, and radioactively tagged molecules given intravenously.
What are the methods of radiation therapy?
The two main types of radiation therapy for treating cancer are external beam radiation and internal radiation therapy. The type of radiation that a doctor recommends will depend on the type of cancer, the size and location of the tumor, and the person's general health.
What are types of radiation?
There are four major types of radiation: alpha, beta, neutrons, and electromagnetic waves such as gamma rays. They differ in mass, energy and how deeply they penetrate people and objects. The first is an alpha particle.
Is Radiation Treatment Safe?
Some patients worry about the safety of radiation therapy. While radiation therapy involves exposure to hazardous radioactive particles, it has been used to safely treat cancer for more than 100 years. Many advancements have been made that have led to safety regulations and checkpoints during treatment.
What machines are used in radiation therapy?
A medical linear accelerator (LINAC) is the device most commonly used for external beam radiation treatments for patients with cancer. It delivers high-energy x-rays or electrons to the region of the patient's tumor.
How long are radiation treatments?
Each radiation therapy treatment takes about 10 minutes. Radiation therapy to try and cure cancer is usually delivered daily, Monday through Friday, for about five to eight weeks. Weekend breaks allow normal cells to recover. Shorter durations of radiation therapy may be used to relieve symptoms.
What is the most common radiation therapy?
The most common type of radiation therapy is external-beam radiation therapy. It delivers radiation from a machine outside the body. It can be used to treat large areas of the body, if needed. A machine called a linear accelerator, or linac, creates the radiation beam for x-ray or photon radiation therapy.
What is another name for radiation treatment?
Other names for radiation treatment are radiation therapy, radiotherapy, irradiation, and x-ray therapy.
What is the goal of radiation therapy?
Its intent is to cure the patient whenever possible and to prolong survival as long as possible. 18 Palliative radiation is playing a larger role in veterinary oncology as owners increasingly seek to improve quality of life, decrease pain, and minimize hospitalization of their pets rather than achieving a cure. Most palliative protocols use lower total radiation doses and a higher dose-per-fraction to accomplish these goals.
What are the disadvantages of preoperative radiation?
Potential disadvantages include increased wound complications and delayed surgical extirpation. Preoperative radiation is not used in every situation. The decision to do so is based on tumor location, surgeon preference, and risk of wound complication.
What are the effects of radiation on the body?
These effects are related to damage to the vascular and connective (stromal) tissue in non- or slowly-proliferating tissue such as the brain, spinal cord, muscle, bone, kidney, and lung.
What are the factors that affect the response to radiation?
Factors affecting acute response to radiation in normal tissue include total dose, overall treatment time (dose intensity), and volume of tissue irradiated. Acute effects in healthy tissue are to be expected and will occur if curative doses are administered, but will resolve with time and supportive care.
What tissues are affected by radiation?
Within the first few wk after the start of radiation, acute effects are typically seen in normal tissues such as bone marrow, epidermis, gastrointestinal cells, and mucosa as well as in neoplastic cells. Factors affecting acute response to radiation in normal tissue include total dose, overall treatment time ...
What is a pet radiology center?
Pet radiology centers are available to veterinarians who wish to refer their oncology patients for radiotherapy. In addition to other resources, the Veterinary Cancer Society provides an online list (vetcancersociety.org) of veterinary radiation therapy centers, including contact information, in 30 states throughout the United States.
Is preoperative radiation therapy better than postoperative radiation?
Preoperative radiation therapy has potential advantages over postoperative radiation. These include treatment of well oxygenated tissue rather than scars, decreased tumor seeding, a smaller treatment volume, and, in some situations, less aggressive surgery.
What doses of irradiation are used for Waldeyer's ring lymphomas?
Acute morbidity of irradiation to doses of 30 Gy to 36 Gy includes xerostomia, loss of taste, and mucositis, which are usually mild to moderate in degree. Depending on the age of the patient, a degree of permanent xerostomia can be seen, as manifested in decreased saliva flow rates upon stimulation. 332 The severity of xerostomia is dependent on the total dose and the volume of salivary gland irradiated. 333 Emami et al estimated that the TD 5/5 for salivary gland function is 32 Gy and the TD 50/5 is 46 Gy. 334 Therefore, careful planning with IMRT should minimize this complication. Similarly for the treatment of unilateral salivary gland lymphomas, IMRT can be used to maximally spare the contralateral parotid gland. Maximum radiation doses of 35 Gy to 40 Gy given in 1.8-Gy to 2-Gy fractions are within the tolerance of all the other critical head and neck tissues such as the spinal cord, neurovascular structures, larynx, trachea, esophagus, oral cavity, lips, and soft tissues. However, proper attention in defining (contouring) these organs at risk to receive lesser doses is part of good IMRT treatment planning practice ( Figure 77-7 ).
How long does it take to get irradiated?
Large portals may be employed, and a dose of 2500–3000 cGy can be delivered during 4–5 weeks to the entire abdomen. The kidneys and possibly the right lobe of the liver are shielded to limit the dose to 2000–2500 cGy. Nausea and vomiting may be associated with this procedure, and therapy is frequently interrupted. Historically, in some centers, abdominal irradiation was delivered by the so-called moving strip technique. Both the whole-abdomen and the moving strip techniques usually finish with a pelvic boost of approximately 2000–3000 cGy.
What is IMRT for NPC?
At many centers, IMRT has become the standard external beam radiation therapy (EBRT) technique for the treatment of NPC. In two separate assessments, Xia and colleagues at UCSF 19 and Hunt and colleagues at Memorial Sloan-Kettering Cancer Center 18 showed that IMRT provided better tumor coverage, with greater percentages of the target tumor volumes receiving the planned prescription dose than a conventional three-field treatment or a three-dimensional conformal plan. In addition to improved tumor coverage, IMRT can deliver lower doses to critical neural structures such as the spinal cord, brainstem, and temporal lobes ( Fig. 10-8 ). In a follow-up report from UCSF, 20 67 patients with NPC had been treated with IMRT, 50 with concurrent chemotherapy and 26 with a brachytherapy boost. At a median follow-up time of 31 months, only two patients had had local or regional disease recurrence. Eight patients had grade 3 or 4 late toxicity. The experience was similar at Memorial Sloan Kettering 21; at a median follow-up time: of 35 months, only 6 of 74 patients treated with IMRT had had local disease recurrence. Rates of severe xerostomia and ototoxicity were low. Several Asian series have also described high local control rates and low rates of severe xerostomia with the use of IMRT for NPC. 49,50
What is RT technique in seminoma?
The RT technique in stage II seminoma is similar to that used in stage I disease. The treatment volume includes the gross tumor as well as the paraaortic and ipsilateral common and external iliac lymph nodes ( Figure 55-4, A ). Previously the dog-leg field was used but data from the German Testicular Cancer Group, although not a randomized study, provide some support for the placement of the inferior extent of the field at the acetabulum. 106 In this study of 87 assessable patients at median follow up of 70 months, only 4 patients relapsed with none distal to the inferior extent of the volume; although this study was small and not designed to test the question of volume reduction it is somewhat reassuring with the low rate of relapse seen. The contralateral iliac lymph nodes may also be treated in cases where lymphadenopathy in the low paraaortic area is deemed to increase the risk of these nodes being involved by tumor. However, such patients often have bulky retroperitoneal lymphadenopathy and are better treated with primary chemotherapy. Adjuvant RT of the supraclavicular lymph nodes in patients with stage II disease has been suggested by some, although it is not justified on a routine basis in view of the low risk of isolated supraclavicular relapse (2 of 79 patients with stage IIA or IIB disease in the PMH series). 108,201
What are the complications of RT in Wilms' tumor?
Lung and mediastinal irradiation with or without doxorubicin have resulted in a higher incidence of cardiac complications such as congestive heart failure (CHF), myocardial infarction, pericardial disease, and valvular heart disease in childhood cancer survivors. 50-52 The demonstration of a threshold dose (>5 Gy) for cardiac mortality highlights the importance of delivering a lower dose to the heart. 52 Dosimetry studies have shown several advantages for the use of whole-lung IMRT over standard anteroposterior/posterior-anterior (AP/PA) techniques. They include superior cardiac protection, superior four-dimensional (4D) lung planning target volume (PTV) dose coverage, and superior dose-uniformity in the lungs with fewer hot spots. 53 Another report has shown that compared to standard AP-PA techniques, the use of whole liver IMRT was associated with superior 4D liver dose coverage and delivered a lower dose to the remaining solitary kidney. 54 Another important finding of these reports is the importance of using 4D simulation to accurately determine the internal target volume (ITV) of the lung and liver after consideration for maximal organ movement during respiration. A National Institutes of Health (NIH)–funded multicenter feasibility study of whole-lung IMRT has recently been completed. If feasible, whole-lung IMRT with 4D planning may replace standard techniques as the new standard of care.
What is the treatment for epithelial carcinoma of the ovary?
Patients with epithelial carcinoma of the ovary who are selected to receive postoperative irradiation should receive treatment of the entire abdomen plus additional radiation to the pelvis. This broad treatment plan is based on an analysis of postirradiation recurrences of stage I and stage II disease, which showed that most of the recurrences were outside the pelvis. There is no lid on the pelvis, and malignant cells are shed from the primary ovarian tumor and circulate throughout the entire abdominal cavity. Lymphatic dissemination is also possible.
Is radiation therapy a second line treatment?
The impetus for renewed interest in second-line radiation therapy is that second-line chemotherapy by and large has not been successful. Cmelak and Kapp reported their experience of 41 patients who failed to respond to chemotherapy. All were treated with whole-abdomen irradiation, usually with a pelvic boost. The 5-year actuarial disease-specific survival was 40% and 50% in the platinum-refractory patients. If residual tumor was <1.5 cm, 5-year disease-free survival was 53%, but it was 0% in patients with >1.5 cm residual disease. Almost one-third of patients failed to complete the planned course of whole-abdomen irradiation because of toxicity. Three patients required surgery to correct gastrointestinal tract problems. Sedlacek and colleagues described 27 patients treated with whole-abdomen irradiation, all after platinum-based chemotherapy. All patients completed the planned course. Survival rate at 5 years was 15%. Patients with microscopic disease survived an average of 63 months, but if disease was >2 cm, average survival was 9 months. Four patients required surgery to correct gastrointestinal problems.
What is radiation therapy called?
When radiation therapy is applied from within the body – with a small source - it is called brachytherapy . The source has the size of a grain of rice and is placed close to or within the tumor. The amount of radiation dose very quickly declines with increasing distance from the source.
What is radiotherapy in medical terms?
An introduction to radiotherapy. Radiotherapy means “to treat using radiation”. You may be familiar with the use of radiation for making an X-ray image. The same kind of X-rays, with a much higher energy, can also be used to treat harmful parts of the human body such as a tumor. Radiotherapy can be applied as an indivudual treatment, ...
What imaging technology is used to identify tumors?
Additional imaging technologies such as functional imaging using MRI or PET-CT can be used to aid the radiation-oncologist in identifying and delineating the tumor. The linac is operated by a group of radiotherapy technologists (RTTs).
What is external beam radiation?
In photon radiotherapy one or multiple beams of radiation are aimed at the tumor from outside of the body. It is therefore also called ‘external beam radiation therapy’. The treatment beams are most commonly generated using a linear accelerator, also called a linac.
Why is photon radiation used for skin tumors?
This type of photon radiation is therefore applied for the treatment of superficial tumors (such as skin tumors). Because of the much lower energy, the treatment machine and the (walls of the) treatment room are much smaller .
What are the different types of radiation therapy?
We are proud to offer various treatment options in all of these three main categories: 1 Photon radiotherapy 2 Proton therapy 3 Brachytherapy
Is radiotherapy safe?
Therefore, the radiotherapy department is safe for all visitors. Treatment on a linac. Prior to treatment, a CT-scan is made of the tumor and surrounding tissues. This allows the planning of the radiation dose in 3D using computer technology.
What is intensity modulated radiation therapy?
Intensity modulated therapy can be described as intensity modulated radiation therapy (IMRT), intensity modulated x-ray or proton therapy (IMXT/IMPT), volumetric arc therapy (VMAT) and other ways. If a treatment is described as IMRT with online re- optimization/re-planning, then it should be categorized as online re-optimization or re-planning.
What is phase radiation?
A “phase” consists of one or more consecutive treatments delivered to the same anatomic volume with no change in the treatment technique. Although the majority of courses of radiation therapy are completed in one or two phases (historically, the “regional” and “boost” treatments) there are occasions in which three or more phases are used, most typically with head and neck malignancies.
What is the unit of measure for radiation?
The unit of measure is centiGray (cGy).
What is 2D therapy?
03 2-D therapy An external beam planning technique using 2 -D imaging, such as plain film x rays or fluoroscopic images, to define the location and size of the treatment beams. Should be clearly described as 2-D therapy. This planning modality is typically used only for palliative treatments.
What is adaptive therapy?
An external beam technique in which the treatment plan is adapted over the course of radiation to reflect changes in the patient’s tumor or normal anatomy using a CT scan obtained at the treatment machine (online). These approaches are sometimes described as CT-guided online re-optimization or online re-planning. If a treatment technique is described as both CT-guided online adaptive therapy as well as another external beam technique (IMRT, SBRT, etc.), then it should be categorized as CT-guided online adaptive therapy. If a treatment is described as “adaptive” but does not include the descriptor “online”, this code should not be used.
What is external beam therapy?
External beam therapy administered using equipment with a maximum energy of less than one (1) million volts (MV). Energies are typically expressed in units of kilovolts (kV). These types of treatments are sometimes referred to as electronic brachytherapy or orthovoltage or superficial therapy. Clinical notes may refer to the brand names of low energy x-ray delivery devices, e.g. Axxent®, INTRABEAM®, or Esteya®.
What is the purpose of AP-PA?
The combination of AP-PA with the aim of sparing the lung tissue and IMRT in an attempt to preserve the esophagus and spinal cord might be considered for treatment planning.
What is the benefit of AP PA field orientation?
Our results show that the use of AP-PA field orientation followed by IMRT offers benefit in terms of critical lung volume irradiation while maintaining the esophagus and the spinal cord within tolerable limits.
What is the P value of IMRT?
P = 0.38 and 0.12 for 3D and IMRT for spinal cord and 0.14 and 0.238 for esophagus respectively. The data demonstrate that when using the combined technique over IMRT or 3D alone, there are better dosimetric results in terms of OAR.
How much radiation is needed for lung cancer?
Lung cancer constitutes a major source of mortality in the western world. The disease is usually diagnosed in advanced stages. Locally advanced disease represents 22% of newly diagnosed cases and is typically associated with 5 year relative survival rates of 24% [ 1 ]. External beam radiation therapy is the essential component in the treatment of stage 3 Non Small Cell Lung Cancer (NSCLC) and Small Cell Lung Cancer (SCLC) patients. Definitive radiation concurrent with chemotherapy is the standard of care of stage 3 NSCLC. Recommended doses of radiation therapy usually are in the range of 60 to 70 Gy [ 2, 3 ]. Wang et al. demonstrated the importance of dose escalation on overall survival in stage 3 NSCLC patients [ 4 ]. The impact of radiation therapy on local control and survival in SCLC has also been described [ 5, 6 ]. The recommended dose schedules for radiation treatment of SCLC are either 1.5 Gy twice daily to 45 Gy total dose or 2 Gy once daily to 60-70 Gy according to NCCN Guidelines (Version 2.2012) [ 7]
Is the weighting of the opposed fields against IMRT in the combined group equally distributed?
The weighting of the opposed fields against IMRT in the combined group was equally distributed.
Does IMRT work with opposed beams?
Little attention has been paid to the fact that intensity modulated radiation therapy (IMRT) techniques do not easily enable treatment with opposed beams. Three treatment plans (3 D conformal, IMRT, and combined (anterior-posterior-posterio-anterior (AP-PA) + IMRT) of 7 patients with centrally-located lung cancer were compared for exposure of lung, spinal cord and esophagus. Combined IMRT and AP-PA techniques offer better lung tissue sparing compared to plans predicated solely on IMRT for centrally-located lung tumors.
Is AP-PA a substitute for IMRT?
Although the latter point may seem prosaic, we maintain that there is simply no substitute for the normal lung tissue avoidance achieved with rudi mentary AP-PA techniques.
How many radiotherapy plans are there for PTV?
Calculated doses to the PTV and organs at risk according to three radiotherapy plans.
How old were the patients in RT planning?
The patients were aged between 50 and 81 years old (median, 73 years old); in total, there were six males and four females. Patient characteristics, including the primary tumor type and involved T-spine levels, are presented in Table I. Written informed consent was obtained from all patients.
What is the OAR reduction rate?
The reduction in the OAR dose using 3DCRT was most prominent for the heart; the mean heart dose was 15.0±3.1 Gy in single PA, 17.3±4.3 Gy in AP/PA and 8.5±1.7 Gy in 3DCRT. When using 3DCRT, the median percentage reduction rate in the mean heart dose was 38.9% (range, 29.4–58.5%) compared with the single PA plan and 47.5% (range, 34.5–67.1%) compared with the AP/PA plan. In addition, the median percentage reduction rate in the mean esophageal dose was 12.8% (range, 4.7–27.9%) compared with the single PA and 15.6% (range, 5.3–29.1%) compared with the AP/PA plan. The median percentage reduction rate in the maximum spinal cord dose was 13.7% (range, 12.1–15.6%) compared with the single PA plan and 1.9% (range, 0.7–4.0%) compared with the AP/PA plan. Furthermore, the median percentage reduction rate in the maximum PTV dose was similar to that of the spinal cord; 14.7% (range, 12.3–17.6%) compared with the single PA plan and 2.9% (range, 1.2–4.0%) compared with the AP/PA plan.
What is 3D conformal RT?
Three-dimensional conformal RT (3DCRT) is positioned between traditional and recent sophisticated technologies. The number of patients with metastatic cancer who receive 3DCRT has increased gradually; however, the beam placement process remains similar to that of 2DRT (5). Few studies have aimed to improve dose distribution using 3DCRT in palliative RT for spine metastases; therefore, the present study aimed to analyze the dosimetric advantages of 3DCRT plans for mid-to-low thoracic spine (T-spine) metastases in terms of sparing adjacent critical organs.
What are the types of cardiac diseases that are caused by radiation?
Types of radiation-induced cardiac disease include pericarditis, congestive heart failure, cardiomyopathy, valve damage, conduction abnormality, coronary artery disease and myocardial infarction (10). In breast cancer, mortality from RT-associated heart disease was reported to offset the improvement of cancer-specific survival due to adjuvant RT (11,12). A clear quantitative dose-volume dependence for the majority of cardiac toxicities remains to be determined (10). A recent study, however, suggested that the rates of major coronary events increase linearly with the mean heart dose by 7.4% per Gy, with no apparent threshold (13). In addition, it has been established that various clinical parameters may aggravate the risk of radiation-induced heart injury; these include age, diabetes mellitus, smoking, hypertension and the use of cardiotoxic anthracycline-containing chemotherapy (10,12). Re-irradiation for painful spine metastases may be required in patients who achieve no pain relief following initial RT or those who outlive the duration of the first RT response. A recent systematic review indicated that the palliative efficacy of re-irradiation is comparable to that of initial RT (14). The 3DCRT approach used in the present study reduced the mean heart dose by 40–50% compared with the 2DRT plans. Minimizing the irradiation dose-volume to the heart may therefore assist in the prevention of radiation-induced cardiac toxicities, including mortality. 3DCRT has also been reported to result in a significant dose reduction to the esophagus (15) and spinal cord (16), although the degree of reduction was less than that to the heart.
What is RT for spine metastases?
Conventional two-dimensional (2D) RT techniques for spine metastases utilize a single posteroanterior (PA) field or anteroposterior/posteroanterior (AP/PA) parallel-opposed fields for thoracic-lumbar-sacral spines or parallel-opposed lateral fields for cervical spines (3). These methods are simple and may be readily practiced; however, these methods do not spare adjacent healthy organs from the harmful effects of irradiation. Since the survival of patients with spine metastases continues to improve, a greater number of patients are at risk of radiation toxicity (4). Novel advanced RT technologies, including stereotactic body RT and intensity-modulated RT, provide highly conformal and accurate irradiation, permitting an increased target dose while reducing the unnecessary irradiation of normal structures. However, these technologies are primarily used for selected non-metastatic patients; in addition, the costs of equipment and treatment limit their general use (5).
Is lung dose affected by 3D CT?
The mean lung dose was negatively affected by the use of posterior oblique fields in 3DCRT in the present study; however, this increase in lung dose was minimal and appeared insufficient to cause clinical effects (20). 2D plans are performed without CT simulation, and the dose is usually calculated on a single transverse contour taken through the center of the target (21). The actual differences between 2D and 3DCRT plans with regard to dose to the PTV and OARs may be greater than those reported in the present study.
Goals of Radiation Therapy
- The goal of definitive or curative radiation therapy is eradication of all viable tumor cells within the patient. Its intent is to cure the patient whenever possible and to prolong survival as long as possible.18Palliative radiation is playing a larger role in veterinary oncology as owners increasingly seek to improve quality of life, decrease pain...
Normal Tissue Response
- Within the first few wk after the start of radiation, acute effects are typically seen in normal tissues such as bone marrow, epidermis, gastrointestinal cells, and mucosa as well as in neoplastic cells. Factors affecting acute response to radiation in normal tissue include total dose, overall treatment time (dose intensity), and volume of tissue irradiated. Acute effects in healthy t…
Pre-Radiation Imaging
- Patients with tumors in complex anatomical locations (e.g., head, neck, body wall) may require CT imaging for planning purposes prior to radiation. Patients treated with palliative courses of radiation may not require computer-based planning depending on tumor size and location. Hemoclips placed at surgery aid in delineating the tumor bed.19 Patient positioning during radio…
Tumor-Specific Radiation Considerations
- A variety of cancers are responsive to radiation therapy. These include brain tumors, nasal tumors, oral tumors, and tumors of the extremities and body. Brain tumor treatment may consist of radiation alone or combined with surgery.20,21The brain tumors reported to favorably respond to radiation include meningioma, schwannoma, choroid plexus tumors, astrocytoma, glioma, an…
Newer Technologies
- 3-D conformal radiation therapy allows the beam to be tightly shaped to the tumor and allows sparing of normal tissues.22Intensity modulated radiation therapy allows the beam collimator to move during treatment, allowing the tumor to be irradiated at different angles and distances during a single treatment. State of art radiation therapy currently includes stereotactic radiosurg…