250 Fractionated radiation therapy for malignant brain tumorsNeurosurgery Vajira
This document discusses fractionated radiation therapy for various malignant brain tumors. It provides details on dose and fractionation schedules for different tumor types, including brain metastases, glioblastoma, anaplastic astrocytoma, anaplastic oligodendroglioma, primary CNS lymphoma, and others. It also discusses prognostic factors, target volumes, recurrence patterns after radiation, and acute and late side effects of radiation therapy to the brain.
The document discusses different types of brain tumors, including gliomas, meningiomas, and medulloblastomas. It covers symptoms, risk factors, diagnosis methods like MRI and CT scans, and treatment options for brain tumors such as surgery, radiation therapy, chemotherapy, and managing increased intracranial pressure. The prognosis depends on the specific type of brain tumor, with some like glioblastoma multiforme having a very poor median survival rate.
250 Fractionated radiation therapy for malignant brain tumorsNeurosurgery Vajira
This document discusses fractionated radiation therapy for various malignant brain tumors. It provides details on dose and fractionation schedules for different tumor types, including brain metastases, glioblastoma, anaplastic astrocytoma, anaplastic oligodendroglioma, primary CNS lymphoma, and others. It also discusses prognostic factors, target volumes, recurrence patterns after radiation, and acute and late side effects of radiation therapy to the brain.
The document discusses different types of brain tumors, including gliomas, meningiomas, and medulloblastomas. It covers symptoms, risk factors, diagnosis methods like MRI and CT scans, and treatment options for brain tumors such as surgery, radiation therapy, chemotherapy, and managing increased intracranial pressure. The prognosis depends on the specific type of brain tumor, with some like glioblastoma multiforme having a very poor median survival rate.
Sixty percent of primary brain tumors are glial tumors, with two-thirds being high-grade. Radiotherapy plays an important role in treating brain tumors, especially for high-grade gliomas, residual disease after surgery, recurrent tumors, and some benign tumors. Techniques include conventional 2D radiotherapy, 3D conformal radiotherapy, stereotactic radiosurgery/radiotherapy using platforms like Gamma Knife or LINAC, and brachytherapy. Emerging techniques like proton beam therapy aim to further reduce radiation exposure to surrounding normal brain tissue. Selection of the right radiotherapy technique depends on the tumor type, location, and available technology.
Malignant Bone Tumours - A lecture for undergraduate students and demonstrators / Tutors featuring general aspects and three common malignant bone tumours viz. Osteosarcoma, Ewing's Sarcoma and Multiple Myeloma
Conformal Radiotherapy in Head and neck cancers is essential in terms of improving quality of life and local control in this era. This presentation aimed at giving an overview of conformal radiotherapy and its role in HNC to a 'general audience'.
Radiation therapy uses high-energy beams to damage cancer cell DNA and destroy their ability to reproduce. There are different types of radiation therapy including external beam radiation delivered via linear accelerator and internal radiation therapy called brachytherapy which places radioactive sources inside the body. Radiation therapy can be used to cure early-stage cancers, reduce tumor symptoms, and prevent cancer recurrence after other treatments. While radiation damages cancer cells, side effects can include skin irritation, fatigue, and damage to nearby healthy tissues. New techniques like IMRT help focus radiation more precisely on the tumor.
This document discusses the use of radiation therapy for various benign diseases. It provides an overview of indications for radiation therapy in benign tumors and conditions of the nervous system, head and neck region, orbits, skin and soft tissues, and skeletal system. Risks of secondary malignancies from radiation are outlined. The document reviews evidence-based radiation doses and techniques for specific benign diseases.
Brain tumors can either be brain metastases, where cancer from another part of the body spreads to the brain, or primary brain tumors called gliomas which develop from glial cells. The most common sources of brain metastases in adults are lung cancer in 50% of cases, breast cancer in 15-20% of cases, and melanoma in 10% of cases. Symptoms of brain metastases include headache in 42% of patients, focal weakness in 27%, mental changes in 31%, seizures in 20%, and gait issues in 17%. Whole brain radiation is a common treatment that typically takes several weeks or months to have an effect, with small tumors potentially disappearing completely by two months. Side effects of brain radiation include temporary hair loss and mild skin
Osteosarcoma is bone cancer that most commonly affects young people and males, as it develops in the largest and fastest growing bones. It has no known cause but certain hereditary genes increase risk. Each year around 800 new cases are diagnosed in the US, with half in children and teens. The five year survival rate is 60-80% if detected early but drops to 15-30% if metastasized. Treatments include surgery, chemotherapy and radiation therapy, while maintaining a healthy weight and not smoking may help prevent osteosarcoma.
Hematopoietic Acute Radiation Syndrome (H-ARS), also known as radiation-acquired aplastic anemia, can develop after significant radiation exposure and results in bone marrow failure and a disorder of blood formation. The syndrome is characterized by a decrease in hematopoietic stem cells and blood cell progenitors, leading to pancytopenia. While radiation is a primary cause, hematotoxic radiation toxins isolated from irradiated mammals have also been shown to induce H-ARS in non-irradiated animals by damaging blood cells and stem cell progenitors through apoptosis and necrosis. The severity of symptoms depends on the dose of toxins administered and can include hemorrhage, infection, and multi-
This document discusses the management of high grade brain tumors. It begins by stating that gliomas make up 60% of primary brain tumors, with two-thirds being clinically aggressive high-grade tumors. The treatment involves a multimodality approach of surgery, radiation therapy, and chemotherapy. For glioblastomas, all three modalities are typically used at initial diagnosis. The standard treatment for glioblastoma is maximal safe surgical resection followed by radiation therapy with concurrent temozolomide chemotherapy and subsequent adjuvant temozolomide chemotherapy. Radiation techniques, chemotherapy options, targeted therapies, and clinical prognostic factors are also discussed.
Learn about the process of radiation therapy to treat soft tissue sarcoma, and how new radiation technology has improved treatment of the disease.
This presentation was given by Elizabeth H. Baldini, MD, MPH, radiation oncology director for the Center for Sarcoma and Bone Oncology at Dana-Farber Cancer Institute. It was originally presented as part of the "15 Years of GIST/Soft Tissue Sarcoma Symposium," held on Sept. 12, 2015 at Dana-Farber in Boston, Mass.
Radiotherapy is a common treatment for brain metastases, but does it improve patients' quality of life? A study of 39 brain metastases patients assessed their quality of life before and after whole brain radiotherapy (WBRT) treatment. The results showed a deterioration in cognitive function, appetite, alertness and hair loss in patients after treatment. There was also a small decline in overall health and high mortality. The study concluded that WBRT does not significantly improve quality of life for brain metastases patients. More research is needed to refine treatment approaches.
This document provides an overview of osteosarcoma, including its definition, epidemiology, pathogenesis, clinical presentation, evaluation, treatment, and subtypes. Osteosarcoma is the second most common primary bone tumor arising from mesenchymal cells. It most often affects people between 12-25 years old. Evaluation involves imaging like x-rays and MRI to determine tumor extent and biopsy for diagnosis. Treatment is typically neoadjuvant chemotherapy followed by surgical resection with wide margins and reconstruction. Prognosis has improved with current multimodal treatment approaches.
This document summarizes results from a clinical trial evaluating the efficacy of adding temozolomide chemotherapy to radiation therapy for the treatment of glioblastoma. The trial involved 573 patients randomized to receive either radiation therapy alone or radiation therapy plus temozolomide. The addition of temozolomide resulted in a statistically significant improvement in median survival (14.6 months vs 12.1 months) and 2-year survival rates (26.5% vs 10.4%). Progression-free survival was also improved in the temozolomide group. Toxicity was found to be minimal. The results provide support for the standard of care now being radiation therapy plus temozolomide for newly diagnosed
This PPT presentation talks about osteosarcoma from the clinical point of view, summarizing the recent guidelines in diagnosis and treatment of osteosarcoma.
When most normal cells grow
old or get damaged, they die, and new cells take their place. Sometimes, this
process goes wrong. New cells form when the body doesn't need them, and old or
damaged cells don't die as they should. The buildup of extra cells often forms
a mass of tissue called a growth or tumor.
Primary brain tumors can be benign or malignant:
Benign brain tumors do not contain cancer cells:
Usually, benign tumors can be removed, and
they seldom grow back.
Benign brain tumors usually have an obvious
border or edge. Cells from benign tumors rarely invade tissues around them.
They don't spread to other parts of the body. However, benign tumors can press
on sensitive areas of the brain and cause serious health problems.
Unlike benign tumors in most other parts of
the body, benign brain tumors are sometimes life threatening.
Benign brain tumors may become malignant.
Malignant brain tumors (also called brain
cancer) contain cancer cells:
Malignant brain tumors are generally more
serious and often are a threat to life.
They are likely to grow rapidly and crowd
or invade the nearby healthy brain tissue.
Cancer cells may break away from malignant
brain tumors and spread to other parts of the brain or to the spinal cord. They
rarely spread to other parts of the body.
Tumor Grade
Doctors group brain tumors by grade.
The grade of a tumor refers to the way the cells look under a microscope:
Grade I: The tissue is benign. The cells
look nearly like normal brain cells, and they grow slowly.
Grade II: The tissue is malignant. The
cells look less like normal cells than do the cells in a Grade I tumor.
Grade III: The malignant tissue has cells
that look very different from normal cells. The abnormal cells are actively
growing (anaplastic).
Grade IV: The malignant tissue has cells
that look most abnormal and tend to grow quickly.
Cells from low-grade tumors (grades I and
II) look more normal and generally grow more slowly than cells from high-grade
tumors (grades III and IV).
Over time, a low-grade tumor may become a
highgrade tumor. However, the change to a high-grade tumor happens more often
among adults than children.
You may want to read the NCI fact sheet Tumor
Grade.
Types of Primary Brain
Tumors
There are many types of primary brain
tumors. Primary brain tumors are named according to the type of cells or the
part of the brain in which they begin. For example, most primary brain tumors
begin in glial cells. This type of tumor is called a glioma.
Among adults, the most common types are:
Astrocytoma:
The tumor arises from star-shaped glial cells called astrocytes.
It can be any grade. In adults, an astrocytoma most often arises in the
cerebrum.
Grade I or II astrocytoma: It may be called
a low-grade glioma.
Grade III astrocytoma: It's sometimes
called a high-grade or an anaplastic astrocytoma.
Grade IV astrocytoma: It may be called a glioblastoma or
malignant astrocytic glioma.
Meningioma:
The tumor arises i
This document discusses radiation therapy for cancer treatment. It describes how the type of cancer, efficacy of other treatments, and patient health determine whether radiation therapy is used. Radiation therapy aims to kill cancer cells using high energy x-rays directed at tumors. Treatment planning involves outlining tumor volumes and minimizing dose to healthy tissues. Radiation damages DNA and prevents cell division, preferentially killing cancer cells. Modern linear accelerators precisely deliver megavoltage x-rays while minimizing surface dose. Treatment techniques like IMRT further improve targeting and reduce side effects.
Radiation therapy plays an important role in the management of many bone tumors as an adjunct to surgery or as primary treatment for inoperable tumors. Newer radiation techniques like IMRT and proton beam therapy allow for more conformal dose distributions that improve local tumor control while reducing damage to surrounding healthy tissues. Radiation is used as primary treatment, post-operatively, or palliatively depending on the tumor type, location, surgical margins, and other factors.
This document discusses guidelines for evaluating radiotherapy treatment plans for primary brain tumors. It provides indications for radiotherapy based on tumor type and extent of resection. Key factors in treatment planning include: contouring target volumes and organs at risk, optimizing dose distribution to cover the target while sparing organs at risk, and quantitatively evaluating plans using tools like isodose distributions, dose volume histograms and indices like coverage, conformity and homogeneity. Plan evaluation ensures the target receives adequate and uniform dose while respecting organ at risk tolerances.
Ionizing radiation interacts with atoms by removing electrons, leaving unstable molecules that break apart into free radicals. Radiation can cause direct or indirect damage to DNA through these free radicals. Radiation is classified by its linear energy transfer (LET), with high-LET radiation depositing energy densely along its path and more directly damaging DNA, while low-LET radiation interacts more randomly and indirectly through free radicals. Common types of ionizing radiation include alpha particles, beta particles, gamma rays, x-rays, and neutrons. Radiation can damage DNA through base modifications, strand breaks, and chromosome aberrations such as translocations or deletions. Actively dividing cells are generally more radiosensitive than mature cells. Fractionated radiation
Sixty percent of primary brain tumors are glial tumors, with two-thirds being high-grade. Radiotherapy plays an important role in treating brain tumors, especially for high-grade gliomas, residual disease after surgery, recurrent tumors, and some benign tumors. Techniques include conventional 2D radiotherapy, 3D conformal radiotherapy, stereotactic radiosurgery/radiotherapy using platforms like Gamma Knife or LINAC, and brachytherapy. Emerging techniques like proton beam therapy aim to further reduce radiation exposure to surrounding normal brain tissue. Selection of the right radiotherapy technique depends on the tumor type, location, and available technology.
Malignant Bone Tumours - A lecture for undergraduate students and demonstrators / Tutors featuring general aspects and three common malignant bone tumours viz. Osteosarcoma, Ewing's Sarcoma and Multiple Myeloma
Conformal Radiotherapy in Head and neck cancers is essential in terms of improving quality of life and local control in this era. This presentation aimed at giving an overview of conformal radiotherapy and its role in HNC to a 'general audience'.
Radiation therapy uses high-energy beams to damage cancer cell DNA and destroy their ability to reproduce. There are different types of radiation therapy including external beam radiation delivered via linear accelerator and internal radiation therapy called brachytherapy which places radioactive sources inside the body. Radiation therapy can be used to cure early-stage cancers, reduce tumor symptoms, and prevent cancer recurrence after other treatments. While radiation damages cancer cells, side effects can include skin irritation, fatigue, and damage to nearby healthy tissues. New techniques like IMRT help focus radiation more precisely on the tumor.
This document discusses the use of radiation therapy for various benign diseases. It provides an overview of indications for radiation therapy in benign tumors and conditions of the nervous system, head and neck region, orbits, skin and soft tissues, and skeletal system. Risks of secondary malignancies from radiation are outlined. The document reviews evidence-based radiation doses and techniques for specific benign diseases.
Brain tumors can either be brain metastases, where cancer from another part of the body spreads to the brain, or primary brain tumors called gliomas which develop from glial cells. The most common sources of brain metastases in adults are lung cancer in 50% of cases, breast cancer in 15-20% of cases, and melanoma in 10% of cases. Symptoms of brain metastases include headache in 42% of patients, focal weakness in 27%, mental changes in 31%, seizures in 20%, and gait issues in 17%. Whole brain radiation is a common treatment that typically takes several weeks or months to have an effect, with small tumors potentially disappearing completely by two months. Side effects of brain radiation include temporary hair loss and mild skin
Osteosarcoma is bone cancer that most commonly affects young people and males, as it develops in the largest and fastest growing bones. It has no known cause but certain hereditary genes increase risk. Each year around 800 new cases are diagnosed in the US, with half in children and teens. The five year survival rate is 60-80% if detected early but drops to 15-30% if metastasized. Treatments include surgery, chemotherapy and radiation therapy, while maintaining a healthy weight and not smoking may help prevent osteosarcoma.
Hematopoietic Acute Radiation Syndrome (H-ARS), also known as radiation-acquired aplastic anemia, can develop after significant radiation exposure and results in bone marrow failure and a disorder of blood formation. The syndrome is characterized by a decrease in hematopoietic stem cells and blood cell progenitors, leading to pancytopenia. While radiation is a primary cause, hematotoxic radiation toxins isolated from irradiated mammals have also been shown to induce H-ARS in non-irradiated animals by damaging blood cells and stem cell progenitors through apoptosis and necrosis. The severity of symptoms depends on the dose of toxins administered and can include hemorrhage, infection, and multi-
This document discusses the management of high grade brain tumors. It begins by stating that gliomas make up 60% of primary brain tumors, with two-thirds being clinically aggressive high-grade tumors. The treatment involves a multimodality approach of surgery, radiation therapy, and chemotherapy. For glioblastomas, all three modalities are typically used at initial diagnosis. The standard treatment for glioblastoma is maximal safe surgical resection followed by radiation therapy with concurrent temozolomide chemotherapy and subsequent adjuvant temozolomide chemotherapy. Radiation techniques, chemotherapy options, targeted therapies, and clinical prognostic factors are also discussed.
Learn about the process of radiation therapy to treat soft tissue sarcoma, and how new radiation technology has improved treatment of the disease.
This presentation was given by Elizabeth H. Baldini, MD, MPH, radiation oncology director for the Center for Sarcoma and Bone Oncology at Dana-Farber Cancer Institute. It was originally presented as part of the "15 Years of GIST/Soft Tissue Sarcoma Symposium," held on Sept. 12, 2015 at Dana-Farber in Boston, Mass.
Radiotherapy is a common treatment for brain metastases, but does it improve patients' quality of life? A study of 39 brain metastases patients assessed their quality of life before and after whole brain radiotherapy (WBRT) treatment. The results showed a deterioration in cognitive function, appetite, alertness and hair loss in patients after treatment. There was also a small decline in overall health and high mortality. The study concluded that WBRT does not significantly improve quality of life for brain metastases patients. More research is needed to refine treatment approaches.
This document provides an overview of osteosarcoma, including its definition, epidemiology, pathogenesis, clinical presentation, evaluation, treatment, and subtypes. Osteosarcoma is the second most common primary bone tumor arising from mesenchymal cells. It most often affects people between 12-25 years old. Evaluation involves imaging like x-rays and MRI to determine tumor extent and biopsy for diagnosis. Treatment is typically neoadjuvant chemotherapy followed by surgical resection with wide margins and reconstruction. Prognosis has improved with current multimodal treatment approaches.
This document summarizes results from a clinical trial evaluating the efficacy of adding temozolomide chemotherapy to radiation therapy for the treatment of glioblastoma. The trial involved 573 patients randomized to receive either radiation therapy alone or radiation therapy plus temozolomide. The addition of temozolomide resulted in a statistically significant improvement in median survival (14.6 months vs 12.1 months) and 2-year survival rates (26.5% vs 10.4%). Progression-free survival was also improved in the temozolomide group. Toxicity was found to be minimal. The results provide support for the standard of care now being radiation therapy plus temozolomide for newly diagnosed
This PPT presentation talks about osteosarcoma from the clinical point of view, summarizing the recent guidelines in diagnosis and treatment of osteosarcoma.
When most normal cells grow
old or get damaged, they die, and new cells take their place. Sometimes, this
process goes wrong. New cells form when the body doesn't need them, and old or
damaged cells don't die as they should. The buildup of extra cells often forms
a mass of tissue called a growth or tumor.
Primary brain tumors can be benign or malignant:
Benign brain tumors do not contain cancer cells:
Usually, benign tumors can be removed, and
they seldom grow back.
Benign brain tumors usually have an obvious
border or edge. Cells from benign tumors rarely invade tissues around them.
They don't spread to other parts of the body. However, benign tumors can press
on sensitive areas of the brain and cause serious health problems.
Unlike benign tumors in most other parts of
the body, benign brain tumors are sometimes life threatening.
Benign brain tumors may become malignant.
Malignant brain tumors (also called brain
cancer) contain cancer cells:
Malignant brain tumors are generally more
serious and often are a threat to life.
They are likely to grow rapidly and crowd
or invade the nearby healthy brain tissue.
Cancer cells may break away from malignant
brain tumors and spread to other parts of the brain or to the spinal cord. They
rarely spread to other parts of the body.
Tumor Grade
Doctors group brain tumors by grade.
The grade of a tumor refers to the way the cells look under a microscope:
Grade I: The tissue is benign. The cells
look nearly like normal brain cells, and they grow slowly.
Grade II: The tissue is malignant. The
cells look less like normal cells than do the cells in a Grade I tumor.
Grade III: The malignant tissue has cells
that look very different from normal cells. The abnormal cells are actively
growing (anaplastic).
Grade IV: The malignant tissue has cells
that look most abnormal and tend to grow quickly.
Cells from low-grade tumors (grades I and
II) look more normal and generally grow more slowly than cells from high-grade
tumors (grades III and IV).
Over time, a low-grade tumor may become a
highgrade tumor. However, the change to a high-grade tumor happens more often
among adults than children.
You may want to read the NCI fact sheet Tumor
Grade.
Types of Primary Brain
Tumors
There are many types of primary brain
tumors. Primary brain tumors are named according to the type of cells or the
part of the brain in which they begin. For example, most primary brain tumors
begin in glial cells. This type of tumor is called a glioma.
Among adults, the most common types are:
Astrocytoma:
The tumor arises from star-shaped glial cells called astrocytes.
It can be any grade. In adults, an astrocytoma most often arises in the
cerebrum.
Grade I or II astrocytoma: It may be called
a low-grade glioma.
Grade III astrocytoma: It's sometimes
called a high-grade or an anaplastic astrocytoma.
Grade IV astrocytoma: It may be called a glioblastoma or
malignant astrocytic glioma.
Meningioma:
The tumor arises i
This document discusses radiation therapy for cancer treatment. It describes how the type of cancer, efficacy of other treatments, and patient health determine whether radiation therapy is used. Radiation therapy aims to kill cancer cells using high energy x-rays directed at tumors. Treatment planning involves outlining tumor volumes and minimizing dose to healthy tissues. Radiation damages DNA and prevents cell division, preferentially killing cancer cells. Modern linear accelerators precisely deliver megavoltage x-rays while minimizing surface dose. Treatment techniques like IMRT further improve targeting and reduce side effects.
Radiation therapy plays an important role in the management of many bone tumors as an adjunct to surgery or as primary treatment for inoperable tumors. Newer radiation techniques like IMRT and proton beam therapy allow for more conformal dose distributions that improve local tumor control while reducing damage to surrounding healthy tissues. Radiation is used as primary treatment, post-operatively, or palliatively depending on the tumor type, location, surgical margins, and other factors.
This document discusses guidelines for evaluating radiotherapy treatment plans for primary brain tumors. It provides indications for radiotherapy based on tumor type and extent of resection. Key factors in treatment planning include: contouring target volumes and organs at risk, optimizing dose distribution to cover the target while sparing organs at risk, and quantitatively evaluating plans using tools like isodose distributions, dose volume histograms and indices like coverage, conformity and homogeneity. Plan evaluation ensures the target receives adequate and uniform dose while respecting organ at risk tolerances.
Ionizing radiation interacts with atoms by removing electrons, leaving unstable molecules that break apart into free radicals. Radiation can cause direct or indirect damage to DNA through these free radicals. Radiation is classified by its linear energy transfer (LET), with high-LET radiation depositing energy densely along its path and more directly damaging DNA, while low-LET radiation interacts more randomly and indirectly through free radicals. Common types of ionizing radiation include alpha particles, beta particles, gamma rays, x-rays, and neutrons. Radiation can damage DNA through base modifications, strand breaks, and chromosome aberrations such as translocations or deletions. Actively dividing cells are generally more radiosensitive than mature cells. Fractionated radiation
This document summarizes a presentation on radiation protection in medicine given by Ossama Anjaq. The presentation covered the following key points:
- The goals and objectives of the presentation were to explain who is responsible for radiation protection, the role of the radiation protection officer in healthcare institutions, the basic principles of radiation protection in medicine and how to develop a radiation protection program.
- It discussed what radiation protection is, who needs it, if tools and equipment are needed, who is responsible for applying radiation protection rules, and what are acceptable exposure levels for workers and patients.
- It also mentioned the Syrian Radiation Protection Regulations issued in 2005 and Law 143 of 2007 which define the responsibilities for radiation and nuclear safety
This document summarizes a presentation on radiation protection in medicine given by Ossama Anjaq. The presentation covered the following key points:
- The goals and objectives of the presentation were to explain who is responsible for radiation protection, the role of the radiation protection officer in healthcare institutions, the basic principles of radiation protection in medicine and how to develop a radiation protection program.
- It discussed what radiation protection is, who needs it, if tools and equipment are needed, who is responsible for applying radiation protection rules, and what are acceptable exposure levels for workers and patients.
- It also mentioned the Syrian Radiation Protection Regulations issued in 2005 and Law 143 of 2007 which define the responsibilities for radiation and nuclear safety
This document discusses radiation protection and safety. It begins with an introduction that outlines common sources of radiation exposure, including natural background radiation and occupational exposure. It then discusses classification of work areas, including monitoring areas and supervised areas. Examples of work area classification are also mentioned. Key aspects of radiation protection covered include identifying radiation sources and their nature, as well as the basic principles of radiation protection good practice - limiting side effects, reducing complications, and decreasing accident likelihood. Responsibilities under the Basic Safety Standards are also outlined.
The document discusses the history and basics of radiotherapy and radiation protection. It describes some key events and discoveries, including Wilhelm Röntgen's discovery of X-rays in 1895, the discovery of radioactivity in the late 1890s, and the early uses of radiation to treat cancers in the late 1890s. It also notes that accurate measurement of absorbed radiation dose is important for treatment success and that dosimetric systems must be properly calibrated and traceable to national and international standards.
The document discusses clinical treatment planning in external photon beam radiotherapy. It covers topics such as volume definition, dose specification, patient data acquisition and simulation, clinical considerations for photon beams including isodose curves, wedge filters, bolus, compensating filters, corrections for contour and tissue inhomogeneities, and beam combinations and clinical applications. The section on clinical considerations for photon beams specifically addresses isodose curves, which are lines connecting points of equal dose distribution, and the use of wedge filters.
- The document discusses clinical treatment planning in external photon beam radiotherapy. It covers topics such as volume definition, dose specification, patient data acquisition and simulation, clinical considerations for photon beams, treatment plan evaluation, and monitor unit calculations.
- Treatment plan evaluation is an important step to study the dose distribution and calculations and ensure the treatment plan dose matches the clinical target. This is done using computer or manual methods. The medical physicist and radiation oncologist must approve the treatment plan before radiotherapy.
- Dose distribution can be evaluated at a few significant points within the target volume, along dose contours in 2D planes of the body or CT slices, or in the entire 3D volume receiving radiation for the region.
This document discusses the biological effects of radiation exposure. It describes internal and external radiation exposure, which can occur through inhalation, ingestion, intravenous injection, or contamination on the skin. The type of damage caused by radiation exposure depends on the dose received, the radiation type (alpha, beta, gamma etc.), the sensitivity of different tissues or organs, and other factors. Radiation damage is measured by assessing harmful health effects in individuals or their offspring resulting from low dose radiation exposures over time.
This document discusses radiation accidents that can occur in brachytherapy. It notes that over 500,000 brachytherapy procedures are performed annually using high-dose-rate brachytherapy. Any error in loading the radioactive source could result in an overdose. More than 500 high-dose-rate brachytherapy accidents have been documented in previous years. Human error and equipment malfunctions are causes of radiation accidents in brachytherapy.