The Ins and Outs Of External Radiation

Radiation therapy is given to patients in a few different manners.  In this article we will discuss external-beam radiation therapy.  This method is done using a linear accelerator, otherwise known as a LINAC.  Depending on the type of cancer being treated, the size of the cancer, the location of the cancer and a few other factors radiation oncologist will prescribe the best manner in which radiation therapy should be given.

Linear accelerators deliver photon beams as x-rays or gamma rays.  A photon is a unit of light or other form of electromagnetic radiation, basically a bundle of energy.  The amount of energy in any given photon will vary.  Photons within gamma rays have the uppermost level of energy followed by x-rays.

LINAC form a stream of quick moving particles using electricity that generates amounts of elevated radiation to treat cancer.  Most often external radiation is given as part of an ongoing, daily treatment plan that lasts several weeks.  Exactly how often the radiation is delivered will depend on a number of aspects such as the total amount of radiation that is to be given.

There are several methods in delivering radiation therapy using external beams.  The most commonly used method by radiation oncologists includes 3-D conformal radiation therapy.  3D-CRT uses advanced computer software and highly developed treatment machines such as linear accelerators to deliver the radiation to the location it is needed without releasing radiation to areas outside of the treatment area.

Other methods of delivering radiation therapy using external beams include:

• IMRT (Intensity-Modulated Radiation Therapy): IMRT uses a linear acceleratorcontrolled by computers to release a specific dosage of radiation to an exact location within a tumor. This is an incredibly advanced form of high precision radiotherapy that uses high energy x-rays to destroy cancerous cells.  This form of treatment is usually given for about five to eight week, taking weekends off to allow non-cancerous cells to heal.  Each treatment takes about ten minutes to administer.
• IGRT (Image-Guided Radiation Therapy): Imaging coordinates are utilized to direct the treatment of radiation therapy. The process uses both two and three dimensional images to guide the course of therapy.
• Tomo Therapy: In tomo therapy a machine that combines IMRT and computed tomography. This treatment options allows radiation specialists to precisely target hard to reach tumors with powerful radiation beams.  The beam is delivered in slices while the patient moves unlike other forms of radiation therapy where the therapy is paused and the treatment is paused and the patient is then set up in a different manner to receive the radiation.
• Stereotactic Radio surgery: Stereotactic radio surgery is mainly used for cancerous tumors in the head. The beam is aimed at the tumor from several directions around the head.  For this type of therapy to work properly it is important that the head is in the exact same position for treatment and that it does not move at all.

In our next installment we will look more in depth at internal radiation therapy and systematic radiation therapy.  The real talk in these installments will allow you as a patient to ask the most appropriate questions when discussing therapy options with your oncologist.

Acceletronics delivers the best equipment performance and service reliability from Linear Accelerators and CT Scanners across all major brands and models.  Our qualified oncology equipment specialists provide a quality customer experience across the USA with timely field maintenance.  We sell, repair, refurbish, move and finance oncology medical systems check out more at http://www.acceletronics.com.

The Ins and Outs Of Internal Radiation

Unlike external radiation therapy which is delivered outside of the body, internal radiation therapy delivers radiation inside or on the body.  There are a few manners in which this type of therapy is delivered: interstitial, intracavitary and episcleral brachytherapy.   Interstitial allows radiation to be placed within the tumor.  Intracavitary allows a source of radiation to be placed in a body cavity near a tumor and episcleral that treats melanoma within the eye using a source that is attached to the eye.

With internal radiation therapy the radiation isotopes are sealed into tiny seeds that are delivered into a patient using needles or catheters.  These isotopes naturally deteriorate as they kill the nearby cancerous cells. Internal radiation therapy may deliver higher dosages of radiation to certain cancerous tumors then treatment using linear accelerators, external radiation therapy, while causing less disruption to the normal healthy cells surrounding the cancerous cells.

Internal radiation can be given in either low or high doses.  When low dose radiation is delivered, radiation therapy will be designed to give off radiation to cancerous cells continuously for several days.  If a higher dose of therapy is to be given, a machine is used to attach tubes to guide the radioactive treatment into place and then removes it at the end of treatment.  This can be done in one or more sessions.  The placement of either high or low doses of internal radiation can be given in either one treatment or several depending on the radiation oncologist’s recommendation.

The placement of the tubes delivering radiation can be placed permanently or temporarily.  For the tubes to be put into place permanently they will be surgically sealed within the patient’s body.  The source of the radiation will be sealed into the patient’s body to emit low doses of radiation continuously.  Once all of the radiation has been given off the pouch will remain sealed in the patient’s body without harm or discomfort.   Permanent therapy is given for low doses of radiation treatment.

With temporary treatment the source carrying the radiation is removed after the treatment is performed.  Temporary, internal radiation therapy can be given as a treatment option for both high and low doses of radiation therapy.  This treatment can be used to treat or boost other forms of radiation therapy for cancer.

Another form of radiation therapy is systemic radiation therapy.  This form of treatment is given either an injection or is made to swallow radioactive materials.  This form of therapy is used for thyroid cancers or other cancers in which treatment needs to travel through the blood to locate and kill the tumor cells.  It is also used regularly for pain relief in patients with bone cancer.

In our next installment on radiation therapy we will discuss why some types of radiation therapy is given in small doses and others in larger doses.  We will also discuss more about external radiation therapy using linear accelerators, LINAC, and internal radiation therapy that delivers radiation in several manners.

Acceletronics delivers the best equipment performance and service reliability from Linear Accelerators and CT Scanners across all major brands and models.  Our qualified oncology equipment specialists provide a quality customer experience across the USA with timely field maintenance.  We sell, repair, refurbish, move and finance oncology medical systems check out more at http://www.acceletronics.com.

Delivering Radiation Therapy To Patients

Most often radiation therapy is given in small doses throughout several weeks through an outpatient facility.  This is especially true of external beam radiation therapy given with the use of a linear accelerator.  Most often radiation will only be administered once a day but occasionally can be given twice daily if recommended.

For most patients receiving radiation therapy as part of their cancer treatment external beam radiation therapy will be given once daily using a linear accelerator.  The treatment is delivered in this manner because a once daily treatment plan helps to minimize the amount of damage that is done to the healthy tissue and normal cells surrounding the cancerous tumors and cells.   Also the likelihood of exposing radiation to cancerous cells during the cell cycle when they are most susceptible to DNA damage increases.

Three other methods in which to distribute radiation have been tested including:

Hypo-fractionation: In order to reduce the number of treatments needed, hypo-fractionation is given in larger doses either once a day or less.

Hyper-fractionation: It is the opposite of hypo-fractionation; smaller doses are given throughout multiple treatments a day.

Accelerated Fractionation: In order to reduce the number of weeks treatment is needed, accelerated fractionation allows treatment to be given in larger doses on a daily or weekly basis.

The hope is to find different options that make receiving treatment more convenient to patients without sacrificing the effectiveness of the therapy.

Patients most often receive radiation therapy before, during or after surgery.  In some patients therapy is given using linear accelerators only without other treatments or surgery while others receive chemotherapy and radiation therapy without surgery.  This will vary due to a number of factors.  The exact point at which radiation is delivered alone or with other cancer treatment methods mainly depends on the patient’s goals and specific type of cancer that is being treated.

When radiation therapy is given before a patient has surgery is done in hopes to shrink the tumor.   This makes it simpler for surgeons to remove the entire tumor decreasing the likelihood it will return after the surgery is complete.   Radiation that is given during surgery is known as IORT, inter-operative radiation therapy.  During surgery radiation is given when normal structures are too close to the cancerous tumor and external-beam radiation would damage the nearby normal tissues.   After surgery radiation is known as post-operative therapy.    Post-operative radiation therapy is given during complicated surgeries to regions such as the abdomen and pelvis.

Acceletronics delivers the best equipment performance and service reliability from Linear Accelerators and CT Scanners across all major brands and models.  Our qualified oncology equipment specialists provide a quality customer experience across the USA with timely field maintenance.  We sell, repair, refurbish, move and finance oncology medical systems check out more at http://www.acceletronics.com.

Radiation Therapy As A Treatment For Cancer

In this installment radiation therapy as a treatment for cancer we will look deeper into why some cancer patients receive radiation and some don’t.  We will also concentrate on how individual radiation therapy differs from patient to patient.

Radiation therapy is administered with two different intents: curative and palliative.  When radiation is given with a curative intent the hope that physicians have is that it will cure the cancer.  The treatment is given with the goal of eliminating the tumor and/or preventing a reoccurrence.  When radiation is administered as a cure it can be delivered alone or in conjunction with surgery and/or chemotherapy.

When radiation is administered with a palliative intent the objective is no longer a cure but instead given to relieve the symptoms and reduce any suffering that may be occurring because of the location of the cancer.  Often palliative radiation therapy is given to patients suffering with brain cancer, when the cancer is pressing on the spine or near the esophagus.

The treatment of cancer is individualized to each unique patient scenario.  Treatment planning begins with a radiation oncologist performs simulation.  During simulation, imaging scans are taken to show the size and location of tumors and the area surrounding the tumor.  There are a number of scans that can be used during this process including CT scans, MRI’s, PET’s and ultrasound.

The most common method involves CT scans.  The process of performing a CT scan is fairly straight forward.  The cancer patient will have pictures taken of the inside of their bodies using a computer that is connected to an x-ray machine.  It is important during any simulation scans that the patient remains still and is located in the exact same location each time.  To help cancer patients stay positioned for longer periods of times, molds and head masks have been constructed.

Once the simulation is performed and the radiation oncologist is pleased with the images obtained they can create a detail plan for treatment.  This plan will include exact details on the size and location of the tumor, the size of the area to be treated, the dose of radiation that will be given, how much of the normal tissue will be exposed and the safest angle to direct the radiation.  Once the plan is approved treatment will begin.

Certain tissues are more delicate than others therefore the method in which radiation therapy is given differs. In some cases radiation is delivered through external beams using a machine known as a linear accelerator or linac for short.  Internal radiation is another method used to provide radiation therapy.  Your radiation oncologist will authorize the best course of action for the specific cancer being addressed.

Acceletronics delivers the best equipment performance and service reliability from Linear Accelerators and CT Scanners across all major brands and models.  Our qualified oncology equipment specialists provide a quality customer experience across the USA with timely field maintenance.  We sell, repair, refurbish, move and finance oncology medical systems check out more at http://www.acceletronics.com.