Recomendados
Mais conteúdo relacionado
Mais procurados
Mais procurados (20)
Semelhante a R osborn rad-onc-101.2013
Semelhante a R osborn rad-onc-101.2013 (20)
Mais de Rex Osborn
Último
Último (20)
R osborn rad-onc-101.2013
- 1. Radiation Oncology 101 2013 US RADIATION ONCOLOGY MARKET INTELLIGENCE REPORT PROVIDED BY REX OSBORN
- 2. FACTOID: During 2011, an estimated 1.2 million patients were treated with radiation at 2,169 hospital and freestanding sites in the United States. FACTOID: Medicare and Medicaid are the predominant sources of payment for radiation oncology. FACTOID: Nearly two-thirds of all cancer patients will receive radiation therapy during their illness. FACTOID: Three cancers – breast cancer, prostate cancer and lung cancer – make up more than half (56 percent) of all patients receiving radiation therapy. FACTOID: For most cancer types treated with radiation therapy, at least 75 percent of the patients are treated with the intent to cure the cancer, rather than control the growth or relieve symptoms like pain. FACTOID: An average linear accelerator is used for 4,500 to 6,500 treatments per year. FACTOID: The average patient receiving curative external beam radiation therapy receives 29 treatments. FACTOID: LINAC, linear accelerators comprised 88 percent of treatment courses. More specialized radiation treatments such as Gamma Knife and brachytherapy make up the remaining 12 percent. Radiation Oncology The Basics
- 3. Treating Cancer in the 21st Century Radiation Oncology is comprised of external and internal radiation based treatments to eradicate, manage and control the growth of cancer. Of the four components deployed to “treat” cancer, Radiation Therapy (RT) – Brachytherapy (Internal) and EBRT will be covered in this presentation
- 4. Radiation Oncology is the therapeutic treatment that uses high energy ionizing radiation to treat cancers. Over the last 5 years, advances in image acquisition, storage, and transfer have dramatically impacted how radiation oncology departments work. No longer does treatment hinge on a few images of questionable quality but on a greater variety of high-quality multi-modality images. Having images available throughout the clinical process makes a tremendous difference in how patients are being treated today. Whether in treatment planning or treatment delivery, clinicians rely heavily on images to make decisions regarding radiation therapy treatment protocols. IMAGE NEXUS Radiation Oncology
- 5. Key Points of Radiation Oncology Radiation therapy uses high-energy radiation to kill cancer cells by damaging their DNA. Radiation therapy can damage normal cells as well as cancer cells. Therefore, treatment must be carefully planned to minimize side effects. The radiation used for cancer treatment may come from a machine outside the body “External”, or it may come from radioactive material placed in the body “Internal” near tumor cells or injected into the bloodstream. A patient may receive radiation therapy before, during, or after surgery, depending on the type of cancer being treated. Some patients receive radiation therapy alone, and some receive radiation therapy in combination with chemotherapy.
- 6. A radiation oncologist develops a patient‟s treatment plan through a process called treatment planning, which begins with simulation. During simulation, detailed imaging scans show the location of a patient‟s tumor and the normal areas around it. These scans are usually computed tomography (CT) scans, but they can also include magnetic resonance imaging (MRI), positron emission tomography (PET), and ultrasound scans. EVERYTHING BEGINS WITH WORKFLOW Treatment Planning
- 7. RadOnc Treatment Planning Treatment plans are typically based on larger numbers of CT images, and other modalities, including MRI, PET, SPECT, and occasionally ultrasound, are employed on a much more frequent basis. Most radiation oncology departments have implemented CT simulation, so they no longer need to borrow time on diagnostic radiology CT scanners. These changes have affected the relationship between radiation oncology and diagnostic radiology. PET/CT images (center) are tools that aid in the simulation (right) in treatment planning (left).
- 8. = Days Radiotherapy (RT) Image Patient Plan Patient Treat Patient Image Guided RT (IGRT) Image Patient Plan Patient Image Patient Treat Patient Offline Adaptive RT Image Patient Plan Patient Treat Patient Online Image Adaptive RT Image Patient Plan Patient Image Patient Plan Patient Treat Patient EVERYTHING BEGINS WITH WORKFLOW RadOnc Workflow
- 10. External beam Radiation Treatment “EBRT” Linear Accelerator Used for External-beam Radiation Therapy EBRT Many types of external-beam radiation therapy are delivered using a machine called a linear accelerator (also called a LINAC). A LINAC uses electricity to form a stream of fast-moving subatomic particles. This creates highenergy radiation that may be used to treat cancer.
- 11. EBRT – 3D Conformal Radiation Therapy 1 of 6 3D Conformal Radiation Therapy . . . . . . . . . . . . Enables radiation oncologists to utilize medical linear accelerator x-ray machines to direct radiation beams at the cancer.
- 12. EBRT – Intensity Modulated RT (IMRT) 2 of 6 Intensity Modulated Radiation Therapy („„IMRT‟‟) Enables radiation oncologists to adjust the intensity of the radiation beam and shape the radiation dose to match the size and shape of the treated tumor with a higher degree of precision than 3D conformal therapy. The net clinical result of this technology is the delivery of higher, more effective radiation doses to tumors while reducing radiation exposure of the surrounding normal, healthy organs.
- 13. EBRT – Stereotactic Radiosurgery (SRS & SBRT) 3 of 6 Stereotactic Radiosurgery („„SRS‟‟) Enables delivery of highly precise, high-dose radiation to small tumors. SRS utilizes additional treatment technologies to deliver treatment with greater precision and accuracy than either IMRT or 3D therapy. SBRT stands for Stereotactic Body Radiation Therapy, a radiation therapy approach which delivers high dose radiation to a target within the body, in either a single treatment session or up to approximately five treatment sessions (each session is typically referred to as a “fraction”).
- 14. EBRT – Image Guided RT (IGRT) 4 of 6 Image Guided Radiation Therapy („„IGRT‟‟) . . . . Enables radiation oncologists to utilize x-ray imaging at the time of treatment to identify the exact position of the tumor within the patient‟s body and adjust the radiation beam to that position for better accuracy.
- 15. EBRT - Volumetric Modulated Arc Therapy (VMAT)5 of 6 Volumetric modulated arc therapy (VMAT) is a more advanced method than IMRT. VMAT enables the physician – in real time – to govern the formation of the beam, the speed of the linear accelerator‟s rotation around the patient and the dosage given to the patient, thus enabling faster and more precise treatment.
- 16. EBRT – Proton Therapy 6 of 6 Proton therapy is another form of external radiation treatment. During the treatment, a particle accelerator is used to aim the proton beams at the tumor. Proton therapy used to a limited extent due to the major investment costs required for the unit.
- 17. Internal Radiation Therapy “IRT” http://www.dana-farber.org/HealthLibrary/Interstitial-Brachytherapy-Video.aspx High-Dose Rate Remote Brachytherapy . . . . . . . . Enables radiation oncologists to treat cancer by internally delivering high doses of radiation directly to the cancer site using temporarily implanted radioactive elements for eradication of cancer. Low-Dose Rate Brachytherapy . . . . . . . . . . . . . . Enables radiation oncologists to treat cancer by internally delivering doses of radiation directly to the cancer over an extended period of time using permanently implanted radioactive elements (e.g., prostate seed implants).
- 18. Systemic Radiation Therapy Systemic radiation uses radioactive drugs called radiopharmaceuticals (RP). These unsealed radiation sources are usually in the form of a liquid. Examples are strontium 89 and iodine 131. The radiopharmaceuticals may be given in a vein (IV) or taken by mouth. They travel throughout the body and collect where the cancer is. This is where they give off their radiation to kill the cancer cells. The radiopharmaceuticals are kept in special containers that hold the radiation inside so it cannot affect others. Treatments are performed in a shielded environment due to ionizing radiation. Technologist adhere to safety protocols for radioactive drugs.
- 19. Radiation Oncology is a $3.1 Billion to $4.2 Billion US Market Place RadOnc Market
- 20. US Market
Notas do Editor
- Eternal Beam Therapy 3D Conformal Radiation Therapy . . . . . . . . . . . . Enables radiation oncologists to utilize medical linear accelerator x-ray machines to direct radiation beams at the cancer. Intensity Modulated Radiation Therapy (‘‘IMRT’’) Enables radiation oncologists to adjust the intensity of the radiation beam and shape the radiation dose to match the size and shape of the treated tumor with a higher degree of precision than 3D conformal therapy. The net clinical result of this technology is the delivery of higher, more effective radiation doses to tumors while reducing radiation exposure of the surrounding normal, healthy organs. Stereotactic Radiosurgery (‘‘SRS’’) . . . . . . . . . . . . Enables delivery of highly precise, high-dose radiation to small tumors. SRS utilizes additional treatment technologies to deliver treatment with greater precision and accuracy than either IMRT or 3D therapy. Historically, SRS was used primarily for brain tumors but recent advancements in imaging and radiation delivery technologies have allowed for expanding applications of this technology to the treatment of extra cranial cancers. Internal Radiation Therapy High-Dose Rate Remote Brachytherapy . . . . . . . . Enables radiation oncologists to treat cancer by internally delivering high doses of radiation directly to the cancer site using temporarily implanted radioactive elements for eradication of cancer. Low-Dose Rate Brachytherapy . . . . . . . . . . . . . . Enables radiation oncologists to treat cancer by internally delivering doses of radiation directly to the cancer over an extended period of time using permanently implanted radioactive elements(e.g., prostate seed implants). Advanced Services Used with External Beam Treatment Therapies Image Guided Radiation Therapy (‘‘IGRT’’) . . . . Enables radiation oncologists to utilize x-ray imaging at the time of treatment to identify the exact position of the tumor within the patient’s body and adjust the radiation beam to that position for better accuracy. External beam radiation therapy (EBRT) is the most common form of radiation treatment and involves the application of radiation from an external source outside the patient’s body. The treatment is delivered by a linear accelerator that rotates around the patient. By delivering the radiation from various angles, the beam is distributed more evenly in the tumor, while also protecting the healthy surrounding tissue. Intensity modulated radiation therapy (IMRT) is an advanced treatment form whereby instead of using one substantial and uniform beam, the patient can be treated using several very small beamlets that can vary in intensity. Accordingly, the radiation can be shaped around the tumor, allowing higher radiation doses,while also minimizing the impact on healthy tissue. Volumetric modulated arc therapy (VMAT) is a more advanced method than IMRT. VMAT enables the physician – in real time – to govern the formation of the beam, the speed of the linear accelerator’s rotation around the patient and the dosage given to the patient, thus enabling faster and more precise treatment. Image guided radiation therapy (IGRT) provides a high level of precision and accuracy by using high-resolution three-dimensional X-ray images of the patient’s soft tissues during treatment. Stereotactic radiosurgery (SRS) is a form of radiation therapy that is generally used to treat tumors and other neurological and cranial diseases. Radiosurgery involves a single exact and high dose being given to small and critically located neurological targets. The method has a high level of precision and is highly effective against tumors, while also having a minimal impact on the surrounding brain tissue. Stereotactic body radiation therapy (SBRT) is a technique that enables a beam to precisely target a tumor in the body and minimizes radiation to normal surrounding tissue. The high level of precision allows small to midsized tumors to be treated with higher doses and a fewer number of fractions, which is known as hypofractionation. Proton therapy is another form of external radiation treatment. During the treatment, a particle accelerator is used to aim the proton beams at the tumor. Proton therapy is only used to a limited extent due to the major investment costs required for the unit. Brachytherapy is also called internal radiation treatment and involves placing a radiation source in or near the treatment area. It allows very high tumor doses to be achieved while limiting the impact on the surrounding organs. The method is common in the treatment of gynecological cancer and prostate cancer, but is alsoused for breast cancer and other forms of cancer
- The increasing prevalence of cancer cases in both developed as well as developing countries is a major concern in the healthcare industry. Cancer care programs employing radiation treatment is significantly improving the survival rates of many cancer types: head, neck , lung, liver, breast, prostate, pancreatic, and gynecological cancer. There has been an increasing life expectancies with the successful treatment of radiation therapy among these cancer patients. In the future, the market will witness an increased demand for Radiation Oncology systems for the treatments of prostate, breast, lung, liver and pancreas cancer. The advancement in technology is driving innovation within the Radiation Oncology market. The companies are aimed in delivering novel Radiation Oncology platforms for less invasive and more responsive therapies. The market place for Radiation Oncology therapy products is characterized by technological innovation; delivering superior cancer-targeting technology and meeting new customer demands.
- Having images available throughout the clinical process makes a tremendous difference in how patients are being treated today. Whether in treatment planning or treatment delivery, clinicians rely heavily on images to make decisions regarding radiation therapy treatment protocols.Typical course of radiationRadiation usually is given daily for 5 days per week for 5 to 8 weeks. Palliative courses may be much briefer (Palliative is end of life care – terminal last stages of cancer). Weekend breaks in treatment allow normal tissue to repair itself. The total number of fractions administered depends on:tumor size and location cancer type reason for treatment patient’s overall health other treatments the patient is receiving.Once therapy begins, daily treatment lasts about 15 to 30 minutes on average. Generally, radiation doesn’t hurt when administered. The patient doesn’t feel or taste anything and hears nothing except the treatment machine. However, if an area near the optic nerve is radiated, patients may see flashes of light and vivid colors from stimulation of the visual cortex. Rarely, patients report an ozone-like odor, a feeling of warmth, or a buzzing sensation.
- What is radiation therapy?Radiation therapy uses high-energy radiation to shrink tumors and kill cancer cells (1). X-rays, gamma rays, and charged particles are types of radiation used for cancer treatment.The radiation may be delivered by a machine outside the body (external-beam radiation therapy), or it may come from radioactive material placed in the body near cancer cells (internal radiation therapy, also called brachytherapy).Systemic radiation therapy uses radioactive substances, such as radioactive iodine, that travel in the blood to kill cancer cells.About half of all cancer patients receive some type of radiation therapy sometime during the course of their treatment.How does radiation therapy kill cancer cells?Radiation therapy kills cancer cells by damaging their DNA (the molecules inside cells that carry genetic information and pass it from one generation to the next) (1). Radiation therapy can either damage DNA directly or create charged particles (free radicals) within the cells that can in turn damage the DNA.Cancer cells whose DNA is damaged beyond repair stop dividing or die. When the damaged cells die, they are broken down and eliminated by the body’s natural processes.Does radiation therapy kill only cancer cells?No, radiation therapy can also damage normal cells, leading to side effects (see Question 10).Doctors take potential damage to normal cells into account when planning a course of radiation therapy (see Question 5). The amount of radiation that normal tissue can safely receive is known for all parts of the body. Doctors use this information to help them decide where to aim radiation during treatment.Why do patients receive radiation therapy?Radiation therapy is sometimes given with curative intent (that is, with the hope that the treatment will cure a cancer, either by eliminating a tumor, preventing cancer recurrence, or both) (1). In such cases, radiation therapy may be used alone or in combination with surgery, chemotherapy, or both.Radiation therapy may also be given with palliative intent. Palliative treatments are not intended to cure. Instead, they relieve symptoms and reduce the suffering caused by cancer.Some examples of palliative radiation therapy are:Radiation given to the brain to shrink tumors formed from cancer cells that have spread to the brain from another part of the body (metastases).Radiation given to shrink a tumor that is pressing on the spine or growing within a bone, which can cause pain.Radiation given to shrink a tumor near the esophagus, which can interfere with a patient’s ability to eat and drink.
- A radiation oncologist develops a patient’s treatment plan through a process called treatment planning, which begins with simulation.During simulation, detailed imaging scans show the location of a patient’s tumor and the normal areas around it. These scans are usually computed tomography (CT) scans, but they can also include magnetic resonance imaging (MRI), positron emission tomography (PET), and ultrasound scans.Computed Tomography Scanner CT scans are often used in treatment planning for radiation therapy. During CT scanning, pictures of the inside of the body are created by a computer linked to an x-ray machine. During simulation and daily treatments, it is necessary to ensure that the patient will be in exactly the same position every day relative to the machine delivering the treatment or doing the imaging. Body molds, head masks, or other devices may be constructed for an individual patient to make it easier for a patient to stay still. Temporary skin marks and even tattoos are used to help with precise patient positioning.Radiation Therapy Head Mask Patients getting radiation to the head may need a mask. The mask helps keep the head from moving so that the patient is in the exact same position for each treatment. After simulation, the radiation oncologist then determines the exact area that will be treated, the total radiation dose that will be delivered to the tumor, how much dose will be allowed for the normal tissues around the tumor, and the safest angles (paths) for radiation delivery.The staff working with the radiation oncologist (including physicists and dosimetrists) use sophisticated computers to design the details of the exact radiation plan that will be used. After approving the plan, the radiation oncologist authorizes the start of treatment. On the first day of treatment, and usually at least weekly after that, many checks are made to ensure that the treatments are being delivered exactly the way they were planned.Radiation doses for cancer treatment are measured in a unit called a gray (Gy), which is a measure of the amount of radiation energy absorbed by 1 kilogram of human tissue. Different doses of radiation are needed to kill different types of cancer cells.Radiation can damage some types of normal tissue more easily than others. For example, the reproductive organs (testicles and ovaries) are more sensitive to radiation than bones. The radiation oncologist takes all of this information into account during treatment planning.If an area of the body has previously been treated with radiation therapy, a patient may not be able to have radiation therapy to that area a second time, depending on how much radiation was given during the initial treatment. If one area of the body has already received the maximum safe lifetime dose of radiation, another area might still be treated with radiation therapy if the distance between the two areas is large enough.The area selected for treatment usually includes the whole tumor plus a small amount of normal tissue surrounding the tumor. The normal tissue is treated for two main reasons:To take into account body movement from breathing and normal movement of the organs within the body, which can change the location of a tumor between treatments.To reduce the likelihood of tumor recurrence from cancer cells that have spread to the normal tissue next to the tumor (called microscopic local spread).
- Goal of therapyThe goal of radiation therapy is to kill cancer cells using the least amount of radiation possible, with treatments spread over an appropriate period. Unlike the low-dose radiation emitted by standard X-rays, radiation therapy delivers high doses capable of destroying cancer cells, rendering them unable to reproduce and spread. Cell damage occurs immediately; cancer cells die over a period of days, weeks, and months and are eliminated by the body. Usually, healthy cells in the radiation treatment field are able to recover. Professionals involved in the care of patients receiving radiation therapy include radiation oncologists, cancer nurses specializing in radiation, physicists, radiation therapists, dosimetrists, clinical trial specialists, social workers, dietitians, care coordinators, and spiritual advisors. A radiation oncologist orders radiation therapy. The total radiation dose is fractionated (given in fractions) rather than all at once, giving normal cells a chance to recover. Each dose that’s delivered is termed a fraction. (See Basic radiation terms defined by clicking on the PDF icon above.) The radiation oncologist and staff involved in planning treatment develop an individualized plan for each patient, including the number of fractions and the amount of radiation administered in each fraction. This approach takes maximum advantage of the difference in radiation tolerance between normal tissues and the patient’s specific cancer type. Typically, radiation therapy is done on an outpatient basis, but occasionally hospital inpatients may receive it. In this case, the radiation oncology staff coordinates the patient’s care and treatment delivery with the inpatient staff. Patients usually receive daily treatments over several weeks. For some, radiation is the only treatment needed. For others, it’s one treatment in a complex multimodality approach, which might also include adjuvant treatments, such as surgery, chemotherapy, or bone marrow transplant. When a cure isn’t possible, palliative radiation may be given to shrink the tumor, which reduces tumor pressure on surrounding tissues and relieves pain. For example, in patients with brain tumors, palliative radiation typically eases headache, nausea, double vision, and balance loss.
- External-beam radiation therapyExternal-beam radiation therapy is most often delivered in the form of photon beams (either x-rays or gamma rays) (1). A photon is the basic unit of light and other forms of electromagnetic radiation. It can be thought of as a bundle of energy. The amount of energy in a photon can vary. For example, the photons in gamma rays have the highest energy, followed by the photons in x-rays.Patients usually receive external-beam radiation therapy in daily treatment sessions over the course of several weeks (see Question 7). The number of treatment sessions depends on many factors, including the total radiation dose that will be given.One of the most common types of external-beam radiation therapy is called 3-dimensional conformal radiation therapy (3D-CRT). 3D-CRT uses very sophisticated computer software and advanced treatment machines to deliver radiation to very precisely shaped target areas.
- Intensity-modulated radiation therapy (IMRT): IMRT uses hundreds of tiny radiation beam-shaping devices, called collimators, to deliver a single dose of radiation (2). The collimators can be stationary or can move during treatment, allowing the intensity of the radiation beams to change during treatment sessions. This kind of dose modulation allows different areas of a tumor or nearby tissues to receive different doses of radiation.Unlike other types of radiation therapy, IMRT is planned in reverse (called inverse treatment planning). In inverse treatment planning, the radiation oncologist chooses the radiation doses to different areas of the tumor and surrounding tissue, and then a high-powered computer program calculates the required number of beams and angles of the radiation treatment (3). In contrast, during traditional (forward) treatment planning, the radiation oncologist chooses the number and angles of the radiation beams in advance and computers calculate how much dose will be delivered from each of the planned beams.The goal of IMRT is to increase the radiation dose to the areas that need it and reduce radiation exposure to specific sensitive areas of surrounding normal tissue. Compared with 3D-CRT, IMRT can reduce the risk of some side effects, such as damage to the salivary glands (which can cause dry mouth, or xerostomia), when the head and neck are treated with radiation therapy (4). However, with IMRT, a larger volume of normal tissue overall is exposed to radiation. Whether IMRT leads to improved control of tumor growth and better survival compared with 3D-CRT is not yet known (4).Tomotherapy: Tomotherapy is a type of image-guided IMRT. A tomotherapy machine is a hybrid between a CT imaging scanner and an external-beam radiation therapy machine (6). The part of the tomotherapy machine that delivers radiation for both imaging and treatment can rotate completely around the patient in the same manner as a normal CT scanner. Tomotherapy machines can capture CT images of the patient’s tumor immediately before treatment sessions, to allow for very precise tumor targeting and sparing of normal tissue.Like standard IMRT, tomotherapy may be better than 3D-CRT at sparing normal tissue from high radiation doses (7). However, clinical trials comparing 3D-CRT with tomotherapy have not been conducted.
- Historically, SRS was used primarily for brain tumors but recent advancements in imaging and radiation delivery technologies have allowed for expanding applications of this technology to the treatment of extra cranial cancers.Stereotactic radiosurgery: Stereotactic radiosurgery (SRS) can deliver one or more high doses of radiation to a small tumor (5, 8). SRS uses extremely accurate image-guided tumor targeting and patient positioning. Therefore, a high dose of radiation can be given without excess damage to normal tissue. SRS can be used to treat only small tumors with well-defined edges. It is most commonly used in the treatment of brain or spinal tumors and brain metastases from other cancer types. For the treatment of some brain metastases, patients may receive radiation therapy to the entire brain (called whole-brain radiation therapy) in addition to SRS.SRS requires the use of a head frame or other device to immobilize the patient during treatment to ensure that the high dose of radiation is delivered accurately.Stereotactic body radiation therapy: Stereotactic body radiation therapy (SBRT) delivers radiation therapy in fewer sessions, using smaller radiation fields and higher doses than 3D-CRT in most cases. By definition, SBRT treats tumors that lie outside the brain and spinal cord. Because these tumors are more likely to move with the normal motion of the body, and therefore cannot be targeted as accurately as tumors within the brain or spine, SBRT is usually given in more than one dose (8). SBRT can be used to treat only small, isolated tumors, including cancers in the lung and liver (8). Many doctors refer to SBRT systems by their brand names, such as the CyberKnife®.
- Image-guided radiation therapy(IGRT): In IGRT, repeated imaging scans (CT, MRI, or PET) are performed during treatment. These imaging scans are processed by computers to identify changes in a tumor’s size and location due to treatment and to allow the position of the patient or the planned radiation dose to be adjusted during treatment as needed. Repeated imaging can increase the accuracy of radiation treatment and may allow reductions in the planned volume of tissue to be treated, thereby decreasing the total radiation dose to normal tissue (5).
- Volumetric modulated arc therapy (VMAT) allows irradiation with simultaneously varying dose rate, gantry speed, collimator, and leaf positions. It has been first introduced by Otto in 2008 [1] and implemented for Varian linear accelerators as RapidArc® [2-8]. Various treatment planning studies have been published, comparing RapidArc® and dynamic intensity modulated radiation therapy (IMRT) or conventional stereotactic treatments with regard to plan quality, delivery time, and monitor units required per fraction dose [2,3,7,9-19], using either in-house developed treatment planning systems (TPS) or the Varian TPS Eclipse. For Elekta linear accelerators volumetric modulated arc therapy became available under the label VMAT in 2008. The only commercially available treatment planning system was ERGO++ (3D Line Medical Systems/Elekta Ltd, Crawley, UK), which, however, requires initial definition of sub-arcs and manual adaptation of the multileaf collimator (MLC) before automatic weight optimization and can therefore not be considered as a fully inverse planning system [20-23]. Fully inverse treatment planning systems for Elekta linear accelerators have become commercially available only recently. A few plan comparison studies have been published [24-26] using the treatment planning system Pinnacle (Philips Healthcare, Andover, MA). All of these studies showed similar plan quality at substantially reduced treatment times for VMAT as compared to IMRT. In December 2009 a new VMAT optimization tool, implemented in OncentraMasterPlan® v3.3, was released clinically, which allows VMAT optimization for Varian and Elekta linear accelerators with a linac-vendor independent planning system.
- By The Numbers: Beam Blowout$144 million to build a five-treatment-room proton-beam therapy center.2 to 3 years to construct a proton-beam facility.20,000 patients treated with protons to date in the U.S. (all with tumors).60 seconds of contact between the proton beam and patient during each session.$841 cost to Medicare for one session of proton therapy.$411 cost to Medicare for one session of X-ray-beam therapy.
- http://www.aboutbrachytherapy.com/en-us/patients/brachytherapy/Pages/what-is-brachytherapy.aspx - Brachytherapy is a type of radiotherapy that can be used to treat many types of cancer.It is sometimes known as ‘internal radiotherapy’, or when used in the treatment of prostate cancer, ‘seed therapy’. Radiotherapy is an important method of treating cancer. It works by destroying cancer cells by targeting them with radiation and stopping them dividing and growing. About 4 out of 10 people with cancer have some type of radiotherapy as part of their treatment.Internal radiation therapyInternal radiation therapy (brachytherapy) is radiation delivered from radiation sources (radioactive materials) placed inside or on the body (12). Several brachytherapy techniques are used in cancer treatment. Interstitial brachytherapy uses a radiation source placed within tumor tissue, such as within a prostate tumor. Intracavitary brachytherapy uses a source placed within a surgical cavity or a body cavity, such as the chest cavity, near a tumor. Episcleral brachytherapy, which is used to treat melanoma inside the eye, uses a source that is attached to the eye.In brachytherapy, radioactive isotopes are sealed in tiny pellets or “seeds.” These seeds are placed in patients using delivery devices, such as needles, catheters, or some other type of carrier. As the isotopes decay naturally, they give off radiation that damages nearby cancer cells.If left in place, after a few weeks or months, the isotopes decay completely and no longer give off radiation. The seeds will not cause harm if they are left in the body (see permanent brachytherapy, described below).Brachytherapy may be able to deliver higher doses of radiation to some cancers than external-beam radiation therapy while causing less damage to normal tissue (1, 12).Brachytherapy can be given as a low-dose-rate or a high-dose-rate treatment:In low-dose-rate treatment, cancer cells receive continuous low-dose radiation from the source over a period of several days (1, 12).In high-dose-rate treatment, a robotic machine attached to delivery tubes placed inside the body guides one or more radioactive sources into or near a tumor, and then removes the sources at the end of each treatment session. High-dose-rate treatment can be given in one or more treatment sessions. An example of a high-dose-rate treatment is the MammoSite® system, which is being studied to treat patients with breast cancer who have undergone breast-conserving surgery.The placement of brachytherapy sources can be temporary or permanent (1, 12):For permament brachytherapy, the sources are surgically sealed within the body and left there, even after all of the radiation has been given off. The remaining material (in which the radioactive isotopes were sealed) does not cause any discomfort or harm to the patient. Permanent brachytherapy is a type of low-dose-rate brachytherapy.For temporary brachytherapy, tubes (catheters) or other carriers are used to deliver the radiation sources, and both the carriers and the radiation sources are removed after treatment. Temporary brachytherapy can be either low-dose-rate or high-dose-rate treatment.Doctors can use brachytherapy alone or in addition to external-beam radiation therapy to provide a “boost” of radiation to a tumor while sparing surrounding normal tissue (12).
- Chemotherapy is systemic drug therapy given either in pills or intravenously. By interfering with the ability of cancer cells to split and grow in the body, chemotherapy can help to shrink the size of existing tumors and can help prevent recurrences in patients who have had cancer.