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External Beam Radiation

About 50 to 60 percent of cancer patients are treated with radiation at some time during their disease. Radiation therapy is a safe and effective treatment for patients of all ages, including children and the elderly.

Radiation therapy is the careful use of high energy radiation by doctors called radiation oncologists to treat cancer. The radiation oncologist may use radiation to cure cancer or to relieve a patient's pain or other symptoms that are caused by cancer. This is called palliation.

Radiation therapy works because the radiation destroys the cancer cells' ability to reproduce. The cancer cells that receive radiation can't make more cancer cells. The body naturally gets rid of these cells.

A cancer patient may be treated with radiation alone. Prostate cancer and larynx cancer are, often treated in this manner.

Sometimes radiation therapy is only part of a patient's treatment. For example, a patient may have radiation therapy after surgery. The radiation therapy destroys my cancer cells that were left behind following surgery. This is called adjuvant treatment.

Patients can be treated with radiation therapy and/or chemotherapy before surgery. This may allow a patient to have less radical surgery than would otherwise be required.

For example, some bladder cancer patients can keep their bladder if they are treated with all three treatments rather than only one treatment.

A radiation oncologist may use radiation from a source outside a patient's body (external beam radiation therapy). Radiation also may be given with radioactive sources that are put inside the patient (brachytherapy).

Linear Accelerator

What are the forms of Radiation Therapy?

Radiation therapy is delivered either externally by a machine (Cobalt tele-therapy or Linear accelerators) called Tele-therapy or external beam radiation, or internally by a radioisotope implanted in or placed close to the tissues called Brachytherapy (comes from Greek word "brachy" meaning "short distance" or "close by").

How does radiation work?

High doses of radiation can kill cancer cells that have multiplied, growing out of control. Radiation is a useful tool for treating cancer because cancer cells divide more rapidly than many normal cells around them. Most normal cells appear to recover more fully from the effects of radiation than cancer cells.

What is the process when a patient is recommended to receive radiation?
Cast / Mask for Head and Neck Radiation	Once the decision is made to treat a patent with radiation, several steps are followed before actual treatment is delivered. Immobilization: An immobilization device (custom designed) helps prevent any patient movements during the x-rays, scans and during daily treatments. Daily reproducibility of the patient position and set-up are vital for maintaining reproducibility and accuracy.
CT Scan simulation Custom block for Pelvic radiation	Simulation: Is a process of obtaining images of the tumor and adjacent areas, to identify and outline the area (s) to be treated. This is accomplished by the technologists (Radiation Therapists) using X-ray Simulator and or special CT-scan simulator, with 2-D or 3-D image capability. Treatment planning and Dosimetry: The areas to be included for treatment and the healthy tissues to be protected from radiation are marked by the physician (Radiation Oncologist). The physicists develop a treatment plan using sophisticated computers (called computer dosimetry) to enable precise direction of the radiation beams in attempting to bypass the normal tissues. Blocks and Treatment Devices: Custom designed blocks or devices are used to block / protect adjacent healthy tissues. We also utilize a computer controlled automatic blocking system called Multi-Leaf Collimator" to shape the fields.
Mantle shaped blocks for Hodgkins' disease	Special blocks are custom designed to protect healthy tissues	Multileaf collimator
	Verification: The patient is positioned in the treatment position and verification x-rays are taken to confirm the plan provided. These films are compared with the simulation films for accuracy and reproducibility. Treatment delivery: Once the treatment plan is verified (using the Varis verification system), the radiation treatment is delivered implementing the treatment plan. During the course of treatment, the patient is periodically checked ("Status Check") to evaluate the response, side effects etc. What happens during treatment? Most patients undergo external beam radiation treatment. Each external beam treatment is painless. The radiation comes from an outside source. It is directed to the cancer inside the patient. A radiation oncologist uses linear accelerators, cobalt machines or orthovoltage x-ray machines for external beam therapy. These machines produce ionizing radiation, such as x-rays, gamma rays, and electron beams, which destroy cancer cells.
Patient Receiving Treatment With Linear Accelerator

The machines produce different, types of radiation that can destroy tumors at different sites within the body The radiation oncologist will choose which machine is best suited to treat each patient.

The patient usually receives external beam therapy four or five times a week. It takes several minutes for each patient to be positioned for treatment. The treatment itself only takes a few minutes. Sometimes a patient is treated twice a day. Rarely, the patient is treated only once or twice a week. An entire course of treatment usually lasts from one to seven weeks depending on the type of cancer and the goal of treatment (cure, adjuvant or palliation).

The treatment team carefully aims the radiation to spare as much as possible the normal tissues surrounding the tumor. Still, radiation may affect some healthy cells. Patients are treated with multiple small doses of radiation with time in between treatments so their healthy cells can repair much of the radiation damage. Generally, radiation is directed to the tumor and the surrounding area. This destroys the main tumor and any nearby tumor spread.

Higher total doses of radiation are needed to destroy the main tumor. Lower doses are given to destroy the, spread of the tumor. This helps to protect normal tissues.

The radiation therapist gives external beam treatment following the radiation oncologist's instructions. The therapist is not in the treatment room with the patient but. closely monitors the, patient on a television screen. There is a microphone in the treatment room. The patient can always talk with the therapist.

During the treatment, the, patient lies very still on a treatment table. The patient can breathe normally during treatment. The radiation therapist is able to move the treatment machine and treatment table. This way the radiation beam can be targeted to the exact area of the tumor. The machine and treatment table may rotate up to 360 degrees if the radiation oncologist wants the radiation to hit the tumor from all angles. The machine also might make noises during treatment. Each treatment generally lasts only a few minutes. Even though the machine on time can vary from day to day, the radiation dose stays the same unless the radiation oncologist changes it.

Most patients do not need to stay in the hospital while they are having external beam therapy. Patients do not see or feel the actual treatment. They can go home following each treatment. Most can continue with normal daily activities. Some patients may need other medical help or services. These patients may need to stay in the hospital, nursing home or a rehabilitation center.

Periodically, the doctor may order blood tests, x-ray examinations and other tests to see how the patient is tolerating treatment. On a regular basis, the radiation oncologist examines and talks with the patient. Other members of the treatment team the radiation therapist, the radiation oncology nurse, the dietician and possibly others also regularly monitor the patient's progress.

When the tumor shrinks, another simulation may be, done. This allows the radiation oncologist to change the treatment so it destroys the rest of the tumor and spares even more normal tissues.

On occasion, x-rays are taken of patients while they are being treated. These x-rays or port films show the radiation oncologist and other members of the treatment team if the treatment is going as planned or needs to be adjusted.

Reception Room:
Receptionist obtains demographic and insurance information, Prepares the chart with medical records (10-15 mins).

Examination Room:
Radiation Oncology nurse interviews the patient, Radiation oncologist obtains pertinent information from the patient and or family members, then examines the patient. Patients then is taken to the Family Room (20-30 mins).

Family Room:
Radiation Oncologist explains to the patient and or family the proposed plan of treatment, treatment course, possible benefits, potential risks, precautions to be taken. A consent is obtained for the proposed therapy and an appointment is given for simulation process and treatment planning. The oncology nurse may counsels the patient regarding nutrition, instructions to be followed and psychosocial issues. Special consultation may be arranged from a nutritionist, psychosocial services and other support services as needed (20-45mins).

Immobilization:
A special cast is made for the area of treatment (cast for head and neck region and pelvic region are shown) . Use the reminder of the text already in place.

Simulation: This procedure (takes approx. 45-60mins) is performed to map out the areas that require radiation treatment and to outline healthy tissues to be protected from radiation.Radiographic images of these areas of interest are obtained (with x-rays or CT scans) by the Radiation Technologists or Radiation Therapists. Radiation Oncologist outlines the target structures and healthy tissues on these films which are used by the Radiation therapists to design special blocks and by the Physicists to obtain special computer calculations. Simulations may be repeated from time to time (usually 2-3 times) during the course of the therapy.

Computer - Treatment Planning and Dosimetry:
Use existing text under the �Process of Radiation Therapy� (Add: Patient does not have to be present during this process)

Information Entry:
All the information thus obtained from simulation and computer planning are entered into the treatment and verification network (Add: Patient does not have to be present during this process)

Custom designed blocks (Left: Pelvis; Right::Hodgkins disease) are shown
Verification: Patient is positioned on the treatment table and the appropriate blocks are inserted into the treatment unit. (see the light field shown for a patient receiving treatment for Hodgkins� disease. Light areas show the area under treatment and surrounding dark areas represent areas under the special blocks to protect lungs, heart and other healthy tissues. X-rays of the target areas are obtained to confirm the plan provided. These films are reviewed for accuracy by the Radiation Oncologist and approved before treatment can begin.

Delivery of Treatment:
Once the treatment plan is verified and approved by the Radiation Oncologist (and the special treatment verification network system) the radiation treatment is delivered by the Radiation Therapists implementing the treatment plan. During the course of the treatment , the patient is periodically assessed for response to the treatment and reactions or side effects to the therapy. Weekly blood counts (or as directed by the Radiation Oncologist) are obtained to monitor white blood cells, platlets etc. which may be temporarily effected by radiation treatments.

Follow-up visit:
Once your course of radiation therapy is finished, it is important to have regular exams to check the results of your treatment. The radiation oncologist will want to see you at least once after your treatment ends. Also, the doctor who referred you for radiation therapy will schedule follow-up visits as needed. Follow-up care, in addition to checking the results of your treatment, might also include more cancer treatment, rehabilitation, and counseling.

Bone Cancer

Bone Metastasis

Cancer of Unknown Primary

Myelodyspastic Syndrome

Osteosarcoma

Pituitary Tumors (Usually not cancer)

Retinoblastoma

Rhabdomyosarcoma

Sarcoma (Adult Sot Tissue Sarcoma)

Thymus Cancer

Hodgkins' Lymphoma

Non-Hodgkins' Lymphoma

Leukemia(Adult Acute)

Leukemia(Adult Chronic)

Gestational Trophoblastic Disease

Melanoma

Non-melanoma

Brain and Central Nervous System

Hodgkins Disease

Non - Hodgkins' Lymphoma

Malignant Mesothelioma of Pleura

Espohagus

Brain / Central Nervous System

Conventional / Standard EBRT

Total Body Irradiation

Total Skin Electron Beam

Low dose rate brachytherapy

High dose rate brachytherapy

Systemic Radiation

Address: Department of Radiation Medicine, Zalmen A. Arlin Cancer Institute, Westchester Medical Center, 95 Grasslands Road, Valhalla, NY 10595, Phone: 914-493-8561, Email: info@cancerdocs-radiation.com