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76-490: RTX may refer to: Science and technology [ edit ] Radiation therapy , is therapy using ionizing radiation, generally as part of cancer treatment to control or kill malignant cells Resiniferatoxin , a natural, high-potency ligand that activates the capsaicin (VR1, TRPV1) receptor Rituximab , a monoclonal antibody used in the treatment of leukemia, lymphomas, transplant rejection and autoimmune disorders RTX2010 ,

152-473: A 2003 action-adventure game for the PlayStation 2, which was developed and published by LucasArts RTX Corporation , formerly Raytheon Technologies, an American defense industry company Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with the title RTX . If an internal link led you here, you may wish to change the link to point directly to

228-525: A break of three months followed by another phase of three gray of radiation for five days. Radiation therapy works by damaging the DNA of cancer cells and can cause them to undergo mitotic catastrophe . This DNA damage is caused by one of two types of energy, photon or charged particle . This damage is either direct or indirect ionization of the atoms which make up the DNA chain. Indirect ionization happens as

304-432: A dose, including whether the patient is receiving chemotherapy, patient comorbidities, whether radiation therapy is being administered before or after surgery, and the degree of success of surgery. Delivery parameters of a prescribed dose are determined during treatment planning (part of dosimetry ). Treatment planning is generally performed on dedicated computers using specialized treatment planning software. Depending on

380-409: A linear accelerator in appearance, but used a sealed radioactive source like the one shown above. 2DXRT mainly consists of a single beam of radiation delivered to the patient from several directions: often front or back, and both sides. Conventional refers to the way the treatment is planned or simulated on a specially calibrated diagnostic X-ray machine known as a simulator because it recreates

456-726: A mild to moderate sun burn. The fatigue often sets in during the middle of a course of treatment and can last for weeks after treatment ends. The irritated skin will heal, but may not be as elastic as it was before. Late side effects occur months to years after treatment and are generally limited to the area that has been treated. They are often due to damage of blood vessels and connective tissue cells. Many late effects are reduced by fractionating treatment into smaller parts. Cumulative effects from this process should not be confused with long-term effects – when short-term effects have disappeared and long-term effects are subclinical, reirradiation can still be problematic. These doses are calculated by

532-426: A neurosurgeon for tumors in the brain or spine. There are two types of stereotactic radiation. Stereotactic radiosurgery (SRS) is when doctors use a single or several stereotactic radiation treatments of the brain or spine. Stereotactic body radiation therapy (SBRT) refers to one or several stereotactic radiation treatments with the body, such as the lungs. Some doctors say an advantage to stereotactic treatments

608-520: A normal oxygen environment. Much research has been devoted to overcoming hypoxia including the use of high pressure oxygen tanks, hyperthermia therapy (heat therapy which dilates blood vessels to the tumor site), blood substitutes that carry increased oxygen, hypoxic cell radiosensitizer drugs such as misonidazole and metronidazole , and hypoxic cytotoxins (tissue poisons), such as tirapazamine . Newer research approaches are currently being studied, including preclinical and clinical investigations into

684-426: A physical examination may find the location of a malignancy . Diagnostic methods include: Apart from diagnoses, these modalities (especially imaging by CT scanning ) are often used to determine operability , i.e. whether it is surgically possible to remove a tumor in its entirety. Currently, a tissue diagnosis (from a biopsy ) by a pathologist is essential for the proper classification of cancer and to guide

760-429: A radiation-hardened microprocessor which has been used in numerous spacecraft RTX toxin (repeats in toxin), a type of toxin secreted by Gram-negative bacteria Computing [ edit ] Ray tracing (graphics) , as implemented by Nvidia, is known as RTX, whereas AMD's implementation differs from RTX, though it's not unusual for people to refer to it as such. Nvidia RTX , a series of Nvidia graphic cards in

836-476: A result of the ionization of water, forming free radicals , notably hydroxyl radicals, which then damage the DNA. In photon therapy, most of the radiation effect is through free radicals. Cells have mechanisms for repairing single-strand DNA damage and double-stranded DNA damage. However, double-stranded DNA breaks are much more difficult to repair, and can lead to dramatic chromosomal abnormalities and genetic deletions. Targeting double-stranded breaks increases

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912-461: A significantly higher dose of radiation (60–70 Gy) to achieve a radical cure. Some types of cancer are notably radioresistant, that is, much higher doses are required to produce a radical cure than may be safe in clinical practice. Renal cell cancer and melanoma are generally considered to be radioresistant but radiation therapy is still a palliative option for many patients with metastatic melanoma. Combining radiation therapy with immunotherapy

988-640: A single treatment is best to improve patient comfort. One fractionation schedule that is increasingly being used and continues to be studied is hypofractionation. This is a radiation treatment in which the total dose of radiation is divided into large doses. Typical doses vary significantly by cancer type, from 2.2 Gy/fraction to 20 Gy/fraction, the latter being typical of stereotactic treatments (stereotactic ablative body radiotherapy, or SABR – also known as SBRT, or stereotactic body radiotherapy) for subcranial lesions, or SRS (stereotactic radiosurgery) for intracranial lesions. The rationale of hypofractionation

1064-508: A strong indication of the primary malignancy. This situation is referred to as " malignancy of unknown primary ", and again, treatment is empirically based on past experience of the most likely origin. Depending upon the cancer identified, follow-up and palliative care will be administered at that time. Certain disorders (such as ALL or AML ) will require immediate admission and chemotherapy , while others will be followed up with regular physical examination and blood tests . Often, surgery

1140-405: A very high failure rate, e.g. women who have received radiation for breast cancer develop late effect chest wall tissue fibrosis and hypovascularity, making successful reconstruction and healing difficult, if not impossible. There are rigorous procedures in place to minimise the risk of accidental overexposure of radiation therapy to patients. However, mistakes do occasionally occur; for example,

1216-660: Is a branch of medicine that deals with the study, treatment, diagnosis, and prevention of cancer . A medical professional who practices oncology is an oncologist . The name's etymological origin is the Greek word ὄγκος ( ónkos ), meaning "tumor", "volume" or "mass". Oncology is concerned with: Medical histories remain an important screening tool: the character of the complaints and nonspecific symptoms (such as fatigue , weight loss , unexplained anemia , fever of unknown origin , paraneoplastic phenomena and other signs) may warrant further investigation for malignancy. Occasionally,

1292-449: Is also related to its size. Due to complex radiobiology , very large tumors are affected less by radiation compared to smaller tumors or microscopic disease. Various strategies are used to overcome this effect. The most common technique is surgical resection prior to radiation therapy. This is most commonly seen in the treatment of breast cancer with wide local excision or mastectomy followed by adjuvant radiation therapy . Another method

1368-401: Is an active area of investigation and has shown some promise for melanoma and other cancers. It is important to distinguish the radiosensitivity of a particular tumor, which to some extent is a laboratory measure, from the radiation "curability" of a cancer in actual clinical practice. For example, leukemias are not generally curable with radiation therapy, because they are disseminated through

1444-517: Is as safe as possible. Radiation therapy is used to treat early stage Dupuytren's disease and Ledderhose disease . When Dupuytren's disease is at the nodules and cords stage or fingers are at a minimal deformation stage of less than 10 degrees, then radiation therapy is used to prevent further progress of the disease. Radiation therapy is also used post surgery in some cases to prevent the disease continuing to progress. Low doses of radiation are used typically three gray of radiation for five days, with

1520-454: Is attempted to remove a tumor entirely. This is only feasible when there is some degree of certainty that the tumor can in fact be removed. When it is certain that parts will remain, curative surgery is often impossible, e.g. when there are metastases , or when the tumor has invaded a structure that cannot be operated upon without risking the patient's life. Occasionally surgery can improve survival even if not all tumour tissue has been removed;

1596-418: Is crucial at this stage as the patient will have to be placed in an identical position during each treatment. Many patient positioning devices have been developed for this purpose, including masks and cushions which can be molded to the patient. Image-guided radiation therapy is a method that uses imaging to correct for positional errors of each treatment session. The response of a tumor to radiation therapy

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1672-502: Is currently a rapid expansion in the use of monoclonal antibody treatments, notably for lymphoma ( Rituximab ) and breast cancer ( Trastuzumab ). Vaccines and other immunotherapies are the subject of intensive research. Approximately 50% of all cancer cases in the Western world can be treated to remission with radical treatment. For pediatric patients, that number is much higher. A large number of cancer patients will die from

1748-546: Is fractionated (spread out over time) for several important reasons. Fractionation allows normal cells time to recover, while tumor cells are generally less efficient in repair between fractions. Fractionation also allows tumor cells that were in a relatively radio-resistant phase of the cell cycle during one treatment to cycle into a sensitive phase of the cycle before the next fraction is given. Similarly, tumor cells that were chronically or acutely hypoxic (and therefore more radioresistant) may reoxygenate between fractions, improving

1824-449: Is measured in grays (Gy), and varies depending on the type and stage of cancer being treated. For curative cases, the typical dose for a solid epithelial tumor ranges from 60 to 80 Gy, while lymphomas are treated with 20 to 40 Gy. Preventive (adjuvant) doses are typically around 45–60 Gy in 1.8–2 Gy fractions (for breast, head, and neck cancers.) Many other factors are considered by radiation oncologists when selecting

1900-414: Is preferably completed within a certain amount of time. For children, a typical fraction size may be 1.5 to 1.8 Gy per day, as smaller fraction sizes are associated with reduced incidence and severity of late-onset side effects in normal tissues. In some cases, two fractions per day are used near the end of a course of treatment. This schedule, known as a concomitant boost regimen or hyperfractionation,

1976-442: Is that they deliver the right amount of radiation to the cancer in a shorter amount of time than traditional treatments, which can often take 6 to 11 weeks. Plus treatments are given with extreme accuracy, which should limit the effect of the radiation on healthy tissues. One problem with stereotactic treatments is that they are only suitable for certain small tumors. Stereotactic treatments can be confusing because many hospitals call

2052-548: Is to reduce the probability of local recurrence by denying clonogenic cells the time they require to reproduce and also to exploit the radiosensitivity of some tumors. In particular, stereotactic treatments are intended to destroy clonogenic cells by a process of ablation, i.e., the delivery of a dose intended to destroy clonogenic cells directly, rather than to interrupt the process of clonogenic cell division repeatedly (apoptosis), as in routine radiotherapy. Different cancer types have different radiation sensitivity. While predicting

2128-503: Is to shrink the tumor with neoadjuvant chemotherapy prior to radical radiation therapy. A third technique is to enhance the radiosensitivity of the cancer by giving certain drugs during a course of radiation therapy. Examples of radiosensitizing drugs include cisplatin , nimorazole , and cetuximab . The impact of radiotherapy varies between different types of cancer and different groups. For example, for breast cancer after breast-conserving surgery , radiotherapy has been found to halve

2204-439: Is under treatment. Side effects are dose-dependent; for example, higher doses of head and neck radiation can be associated with cardiovascular complications, thyroid dysfunction, and pituitary axis dysfunction. Modern radiation therapy aims to reduce side effects to a minimum and to help the patient understand and deal with side effects that are unavoidable. The main side effects reported are fatigue and skin irritation, like

2280-443: Is used on tumors that regenerate more quickly when they are smaller. In particular, tumors in the head-and-neck demonstrate this behavior. Patients receiving palliative radiation to treat uncomplicated painful bone metastasis should not receive more than a single fraction of radiation. A single treatment gives comparable pain relief and morbidity outcomes to multiple-fraction treatments, and for patients with limited life expectancy,

2356-403: The DNA of cancerous tissue leading to cellular death . To spare normal tissues (such as skin or organs which radiation must pass through to treat the tumor), shaped radiation beams are aimed from several angles of exposure to intersect at the tumor, providing a much larger absorbed dose there than in the surrounding healthy tissue. Besides the tumor itself, the radiation fields may also include

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2432-615: The European Organisation for Research and Treatment of Cancer (EORTC) or the National Cancer Research Network (NCRN). The most valued companies worldwide whose leading products are in Oncology include Pfizer (United States), Roche (Switzerland), Merck (United States), AstraZeneca (United Kingdom), Novartis (Switzerland) and Bristol-Myers Squibb (United States) who are active in

2508-594: The GeForce brand .rtx (ring tone XML file extension), of the Ring Tone Transfer Language RTX (operating system) , a real-time operating system extension for Microsoft Windows Keil RTX, a real-time operating system (RTOS) produced by Keil for ARM devices Other uses [ edit ] RTX, a band formed by Jennifer Herrema RTX (event) , a video game and internet convention held annually in three cities RTX Red Rock ,

2584-542: The US' 1.2M invasive cancer cases diagnosed in 2022 received radiation therapy in their treatment program. Different cancers respond to radiation therapy in different ways. The response of a cancer to radiation is described by its radiosensitivity. Highly radiosensitive cancer cells are rapidly killed by modest doses of radiation. These include leukemias , most lymphomas , and germ cell tumors . The majority of epithelial cancers are only moderately radiosensitive, and require

2660-434: The ability to delineate tumors and adjacent normal structures in three dimensions using specialized CT and/or MRI scanners and planning software. Virtual simulation, the most basic form of planning, allows more accurate placement of radiation beams than is possible using conventional X-rays, where soft-tissue structures are often difficult to assess and normal tissues difficult to protect. Oncology#Therapy Oncology

2736-422: The body, brachytherapy uses sealed radioactive sources placed precisely in the area under treatment, and systemic radioisotopes are given by infusion or oral ingestion. Brachytherapy can use temporary or permanent placement of radioactive sources. The temporary sources are usually placed by a technique called afterloading. In afterloading a hollow tube or applicator is placed surgically in the organ to be treated, and

2812-420: The body. Lymphoma may be radically curable if it is localized to one area of the body. Similarly, many of the common, moderately radioresponsive tumors are routinely treated with curative doses of radiation therapy if they are at an early stage. For example, non-melanoma skin cancer , head and neck cancer , breast cancer , non-small cell lung cancer , cervical cancer , anal cancer , and prostate cancer . With

2888-428: The charged particle radiation source and the tumor and sets a finite range for tissue damage after the tumor has been reached. In contrast, IMRT's use of uncharged particles causes its energy to damage healthy cells when it exits the body. This exiting damage is not therapeutic, can increase treatment side effects, and increases the probability of secondary cancer induction. This difference is very important in cases where

2964-419: The close proximity of other organs makes any stray ionization very damaging (example: head and neck cancers ). This X-ray exposure is especially bad for children, due to their growing bodies, and while depending on a multitude of factors, they are around 10 times more sensitive to developing secondary malignancies after radiotherapy as compared to adults. The amount of radiation used in photon radiation therapy

3040-490: The disease, and a significant proportion of patients with incurable cancer will die of other causes. There may be ongoing issues with symptom control associated with progressive cancer, and also with the treatment of the disease. These problems may include pain , nausea , anorexia , fatigue , immobility, and depression . Not all issues are strictly physical: personal dignity may be affected. Moral and spiritual issues are also important. While many of these problems fall within

3116-449: The draining lymph nodes if they are clinically or radiologically involved with the tumor, or if there is thought to be a risk of subclinical malignant spread. It is necessary to include a margin of normal tissue around the tumor to allow for uncertainties in daily set-up and internal tumor motion. These uncertainties can be caused by internal movement (for example, respiration and bladder filling) and movement of external skin marks relative to

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3192-447: The exception of oligometastatic disease, metastatic cancers are incurable with radiation therapy because it is not possible to treat the whole body. Modern radiation therapy relies on a CT scan to identify the tumor and surrounding normal structures and to perform dose calculations for the creation of a complex radiation treatment plan. The patient receives small skin marks to guide the placement of treatment fields. Patient positioning

3268-506: The general health of the patient. Total body irradiation (TBI) is a radiation therapy technique used to prepare the body to receive a bone marrow transplant . Brachytherapy , in which a radioactive source is placed inside or next to the area requiring treatment, is another form of radiation therapy that minimizes exposure to healthy tissue during procedures to treat cancers of the breast, prostate, and other organs. Radiation therapy has several applications in non-malignant conditions, such as

3344-477: The intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=RTX&oldid=1227129647 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages Radiation therapy Radiation therapy is commonly applied to the cancerous tumor because of its ability to control cell growth. Ionizing radiation works by damaging

3420-433: The least common among people with radiation-induced hypopituitarism. Changes in prolactin -secretion is usually mild, and vasopressin deficiency appears to be very rare as a consequence of radiation. Delayed tissue injury with impaired wound healing capability often develops after receiving doses in excess of 65 Gy. A diffuse injury pattern due to the external beam radiotherapy 's holographic isodosing occurs. While

3496-451: The linear accelerator actions (or sometimes by eye), and to the usually well-established arrangements of the radiation beams to achieve a desired plan . The aim of simulation is to accurately target or localize the volume which is to be treated. This technique is well established and is generally quick and reliable. The worry is that some high-dose treatments may be limited by the radiation toxicity capacity of healthy tissues which lie close to

3572-425: The macroscopic tumor has already been completely removed surgically but there is a reasonable statistical risk that it will recur. Chemotherapy and radiotherapy are commonly used for palliation, where disease is clearly incurable: in this situation the aim is to improve the quality of life and to prolong it. Hormone manipulation is well established, particularly in the treatment of breast and prostate cancer. There

3648-457: The major limitations of photon radiation therapy is that the cells of solid tumors become deficient in oxygen . Solid tumors can outgrow their blood supply, causing a low-oxygen state known as hypoxia . Oxygen is a potent radiosensitizer , increasing the effectiveness of a given dose of radiation by forming DNA-damaging free radicals. Tumor cells in a hypoxic environment may be as much as 2 to 3 times more resistant to radiation damage than those in

3724-411: The next step of treatment. On extremely rare instances when this is not possible, "empirical therapy" (without an exact diagnosis) may be considered, based on the available evidence (e.g. history, x-rays and scans.) On very rare occasions, a metastatic lump or pathological lymph node is found (typically in the neck) for which a primary tumor cannot be found. However, immunohistochemical markers often give

3800-806: The offspring. In males previously having undergone radiotherapy, there appears to be no increase in genetic defects or congenital malformations in their children conceived after therapy. However, the use of assisted reproductive technologies and micromanipulation techniques might increase this risk. Hypopituitarism commonly develops after radiation therapy for sellar and parasellar neoplasms, extrasellar brain tumors, head and neck tumors, and following whole body irradiation for systemic malignancies. 40–50% of children treated for childhood cancer develop some endocrine side effect. Radiation-induced hypopituitarism mainly affects growth hormone and gonadal hormones . In contrast, adrenocorticotrophic hormone (ACTH) and thyroid stimulating hormone (TSH) deficiencies are

3876-662: The patient's personality, religion, culture, and family life. Though these issues are complex and emotional, the answers are often achieved by the patient seeking counsel from trusted personal friends and advisors. It requires a degree of sensitivity and very good communication on the part of the oncology team to address these problems properly. There is a tremendous amount of research being conducted on all frontiers of oncology, ranging from cancer cell biology, and radiation therapy to chemotherapy treatment regimens and optimal palliative care and pain relief . Next-generation sequencing and whole-genome sequencing have completely changed

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3952-409: The patient. Serious radiation complications may occur in 5% of RT cases. Acute (near immediate) or sub-acute (2 to 3 months post RT) radiation side effects may develop after 50 Gy RT dosing. Late or delayed radiation injury (6 months to decades) may develop after 65 Gy. Most side effects are predictable and expected. Side effects from radiation are usually limited to the area of the patient's body that

4028-414: The probability that cells will undergo cell death . Cancer cells are generally less differentiated and more stem cell -like; they reproduce more than most healthy differentiated cells, and have a diminished ability to repair sub-lethal damage. Single-strand DNA damage is then passed on through cell division; damage to the cancer cells' DNA accumulates, causing them to die or reproduce more slowly. One of

4104-481: The procedure is referred to as "debulking" (i.e. reducing the overall amount of tumour tissue). Surgery is also used for the palliative treatment of some cancers, e.g. to relieve biliary obstruction, or to relieve the problems associated with some cerebral tumors. The risks of surgery must be weighed against the benefits. Chemotherapy and radiotherapy are used as a first-line radical therapy in several malignancies. They are also used for adjuvant therapy, i.e. when

4180-402: The radiation delivery method, several angles or sources may be used to sum to the total necessary dose. The planner will try to design a plan that delivers a uniform prescription dose to the tumor and minimizes dose to surrounding healthy tissues. In radiation therapy, three-dimensional dose distributions may be evaluated using the dosimetry technique known as gel dosimetry . The total dose

4256-402: The radiation oncologist and many factors are taken into account before the subsequent radiation takes place. During the first two weeks after fertilization , radiation therapy is lethal but not teratogenic . High doses of radiation during pregnancy induce anomalies , impaired growth and intellectual disability , and there may be an increased risk of childhood leukemia and other tumors in

4332-585: The radiation therapy machine Therac-25 was responsible for at least six accidents between 1985 and 1987, where patients were given up to one hundred times the intended dose; two people were killed directly by the radiation overdoses. From 2005 to 2010, a hospital in Missouri overexposed 76 patients (most with brain cancer) during a five-year period because new radiation equipment had been set up incorrectly. Although medical errors are exceptionally rare, radiation oncologists, medical physicists and other members of

4408-519: The radiation therapy treatment team are working to eliminate them. In 2010 the American Society for Radiation Oncology (ASTRO) launched a safety initiative called Target Safely that, among other things, aimed to record errors nationwide so that doctors can learn from each and every mistake and prevent them from recurring. ASTRO also publishes a list of questions for patients to ask their doctors about radiation safety to ensure every treatment

4484-421: The rate at which the disease recurs. In pancreatic cancer, radiotherapy has increased survival times for inoperable tumors. Radiation therapy (RT) is in itself painless. Many low-dose palliative treatments (for example, radiation therapy to bony metastases ) cause minimal or no side effects, although short-term pain flare-up can be experienced in the days following treatment due to oedema compressing nerves in

4560-517: The remit of the oncologist, palliative care has matured into a separate, closely allied specialty to address the problems associated with advanced disease. Palliative care is an essential part of the multidisciplinary cancer care team. Palliative care services may be less hospital-based than oncology, with nurses and doctors who are able to visit the patient at home. There are a number of recurring ethical questions and dilemmas in oncological practice. These include: These issues are closely related to

4636-683: The sensitivity based on genomic or proteomic analyses of biopsy samples has proven challenging, the predictions of radiation effect on individual patients from genomic signatures of intrinsic cellular radiosensitivity have been shown to associate with clinical outcome. An alternative approach to genomics and proteomics was offered by the discovery that radiation protection in microbes is offered by non-enzymatic complexes of manganese and small organic metabolites. The content and variation of manganese (measurable by electron paramagnetic resonance) were found to be good predictors of radiosensitivity , and this finding extends also to human cells. An association

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4712-451: The sources are loaded into the applicator after the applicator is implanted. This minimizes radiation exposure to health care personnel. Particle therapy is a special case of external beam radiation therapy where the particles are protons or heavier ions . A review of radiation therapy randomised clinical trials from 2018 to 2021 found many practice-changing data and new concepts that emerge from RCTs, identifying techniques that improve

4788-403: The standard treatment for almost all tumor sites. More recently other forms of imaging are used including MRI, PET, SPECT and Ultrasound. Stereotactic radiation is a specialized type of external beam radiation therapy. It uses focused radiation beams targeting a well-defined tumor using extremely detailed imaging scans. Radiation oncologists perform stereotactic treatments, often with the help of

4864-560: The target tumor volume. An example of this problem is seen in radiation of the prostate gland, where the sensitivity of the adjacent rectum limited the dose which could be safely prescribed using 2DXRT planning to such an extent that tumor control may not be easily achievable. Prior to the invention of the CT, physicians and physicists had limited knowledge about the true radiation dosage delivered to both cancerous and healthy tissue. For this reason, 3-dimensional conformal radiation therapy has become

4940-473: The targeted tumor receives the majority of radiation, healthy tissue at incremental distances from the center of the tumor are also irradiated in a diffuse pattern due to beam divergence. These wounds demonstrate progressive, proliferative endarteritis , inflamed arterial linings that disrupt the tissue's blood supply. Such tissue ends up chronically hypoxic , fibrotic , and without an adequate nutrient and oxygen supply. Surgery of previously irradiated tissue has

5016-485: The therapeutic ratio, techniques that lead to more tailored treatments, stressing the importance of patient satisfaction, and identifying areas that require further study. The following three sections refer to treatment using X-rays. Historically conventional external beam radiation therapy (2DXRT) was delivered via two-dimensional beams using kilovoltage therapy X-ray units, medical linear accelerators that generate high-energy X-rays, or with machines that were similar to

5092-431: The therapy has survival benefit and can be curative). It is also common to combine radiation therapy with surgery , chemotherapy, hormone therapy , immunotherapy or some mixture of the four. Most common cancer types can be treated with radiation therapy in some way. The precise treatment intent (curative, adjuvant, neoadjuvant therapeutic , or palliative) will depend on the tumor type, location, and stage , as well as

5168-463: The tissue – the beam does not broaden much, stays focused on the tumor shape, and delivers small dose side-effects to surrounding tissue. They also more precisely target the tumor using the Bragg peak effect. See proton therapy for a good example of the different effects of intensity-modulated radiation therapy (IMRT) vs. charged particle therapy . This procedure reduces damage to healthy tissue between

5244-414: The treated area. Higher doses can cause varying side effects during treatment (acute side effects), in the months or years following treatment (long-term side effects), or after re-treatment (cumulative side effects). The nature, severity, and longevity of side effects depends on the organs that receive the radiation, the treatment itself (type of radiation, dose, fractionation , concurrent chemotherapy), and

5320-401: The treatment of trigeminal neuralgia , acoustic neuromas , severe thyroid eye disease , pterygium , pigmented villonodular synovitis , and prevention of keloid scar growth, vascular restenosis , and heterotopic ossification . The use of radiation therapy in non-malignant conditions is limited partly by worries about the risk of radiation-induced cancers. It is estimated that half of

5396-425: The treatments by the name of the manufacturer rather than calling it SRS or SBRT. Brand names for these treatments include Axesse, Cyberknife , Gamma Knife , Novalis, Primatom, Synergy, X-Knife , TomoTherapy , Trilogy and Truebeam . This list changes as equipment manufacturers continue to develop new, specialized technologies to treat cancers. The planning of radiation therapy treatment has been revolutionized by

5472-508: The tumor cell kill. Fractionation regimens are individualised between different radiation therapy centers and even between individual doctors. In North America, Australia, and Europe, the typical fractionation schedule for adults is 1.8 to 2 Gy per day, five days a week. In some cancer types, prolongation of the fraction schedule over too long can allow for the tumor to begin repopulating, and for these tumor types, including head-and-neck and cervical squamous cell cancers, radiation treatment

5548-470: The tumor position. Radiation oncology is the medical specialty concerned with prescribing radiation, and is distinct from radiology , the use of radiation in medical imaging and diagnosis . Radiation may be prescribed by a radiation oncologist with intent to cure or for adjuvant therapy. It may also be used as palliative treatment (where cure is not possible and the aim is for local disease control or symptomatic relief) or as therapeutic treatment (where

5624-454: The understanding of cancers. Identification of novel genetic/molecular markers will change the methods of diagnosis and treatment, paving the way for personalized medicine. Therapeutic trials often involve patients from many different hospitals in a particular region. In the UK, patients are often enrolled in large studies coordinated by Cancer Research UK (CRUK), Medical Research Council (MRC),

5700-551: The use of an oxygen diffusion-enhancing compound such as trans sodium crocetinate as a radiosensitizer. Charged particles such as protons and boron , carbon , and neon ions can cause direct damage to cancer cell DNA through high-LET ( linear energy transfer ) and have an antitumor effect independent of tumor oxygen supply because these particles act mostly via direct energy transfer usually causing double-stranded DNA breaks. Due to their relatively large mass, protons and other charged particles have little lateral side scatter in

5776-402: Was confirmed between total cellular manganese contents and their variation, and clinically inferred radioresponsiveness in different tumor cells, a finding that may be useful for more precise radiodosages and improved treatment of cancer patients. Historically, the three main divisions of radiation therapy are: The differences relate to the position of the radiation source; external is outside

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