Notice of Data Security Incident

  • Printer Friendly Version
  • Decrease Text Size
  • Increase Text Size
  • PDF

Radiation Therapy

hospital buildingRadiation therapies offered at the HealthAlliance Hospital carefully target and regulate high-energy radiation to destroy cancer cells. Radiation therapy is also called radiotherapy, X-ray therapy, cobalt treatment or irradiation. It can be used alone or in conjunction with other treatments. Radiation therapy targets the cells within the area that is diseased. It can be used to shrink a cancerous tumor before surgery; stop the growth of cancer cells after surgery; or in conjunction with anticancer drugs to destroy a malignant tumor.

How does radiation therapy work?

You may have some concerns that the radiation kills healthy cells along with the diseased cells. You should know, therefore, that radiation is much more deadly to cancer cells than to normal cells. The reason for this is that cancer cells divide more rapidly than do healthy cells. Cells are more vulnerable when they are in the process of dividing. Add to this the fact that normal cells can recover more easily from the effects of radiation while cancer cells have a much more difficult time.


External Radiation

This form of radiation is directed at a cancer from outside the body by a machine such as a linear accelerator. This allows your doctor to treat a region or multiple regions of your body. It is the most common of all radiation therapies. During treatment, a beam of radiation is directed through the skin to a tumor and the immediate surrounding area in order to destroy the main tumor and any nearby cancer cells. Like having a chest X-ray, there is no pain or feeling of any kind during the treatment. The machine never touches you.

In a process called simulation, your doctor will determine the exact locations which are to receive radiation. This is done by computerized tomography (CT). The CT simulation process allows a complete three-dimensional view of the areas that need to be targeted and the areas to avoid. Each treatment takes about 15 minutes and is performed on an outpatient basis over a number of weeks.

3D Conformal Radiotherapy

Today, most radiation treatment plans compute the radiation dose and distribution in a 3D setting. A detailed three-dimensional representation of the tumor and surrounding organs is created. Your radiation oncologist can then shape the beams to exactly the size and shape of the tumor and visualize the surrounding normal tissues.

IMRT: The latest advancement

Treatments are evolving. And new methods are constantly being developed to administer radiation therapy. Intensity Modulated Radiation Therapy (IMRT) is one such treatment available at the Cancer Center.

IMRT treatment is a type of 3-D radiation in which the delivered radiation conforms to the tumor shape, thus minimizing even further any damage to healthy tissues. IMRT allows radiation beams to be divided up and delivered in different intensities and directions to match the tumor’s shape. IMRT allows us to treat smaller targets more safely.

IGRT: Image Guided Radiation Therapy

Image Guidance is a further refinement of our ability to deliver the treatment in the most accurate fashion. Our linear accelerator will be equipped with the Varian On Board Imager (OBI). This X-ray device allows us to image and internal target before treatment. Targeting can be done with either conventional X-rays to detect implanted markers or with a CT scan. These techniques improve accuracy and may allow for higher doses of radiation.

Stereotactic Radiotherapy (for future installation)

Stereotactic radiosurgery (SRT) is a unique form of radiation therapy that uses a very precise, high-dose X-ray beam to target a small area of the brain and body. This additional precision is achieved by using special devises to ensure accurate positioning and through Image Guidance to ensure the exact location of the tumor for the treatment. Each SRT treatment delivers a high dose of therapy and thus fewer treatments are needed. Because SRT depends on precision, some additional steps are required in the planning and implementation.

Brachytherapy, or Internal Radiation

Brachytherapy (brak-e-THER-up-pee) internal radiation treatment is the science of placing radioactive materials inside either a cancer or an organ with cancer. Because the radiation source is placed so close to or inside the tumor, a large dose of radiation can be delivered to the tumor with minimal exposure to surrounding normal tissue.

The radioactive sources used in the brachytherapy are small capsules or seeds. These can be placed permanently. The capsules remain in the body after the radiation has been expended and the seeds are no longer radioactive.

Alternatively, tiny tubes or catheters can be temporarily placed in the body for a day or more to allow a very strong radioactive seed to travel through the catheter, delivering treatment deep inside the body without passing through critical organs. This is called a ‘temporary implant’. Because the radiation is delivered with a highly radioactive source, it is also called High Dose Rate (HDR) Brachytherapy.

Our team consists of the following medical professionals.

Radiation Oncologist (physician)

The radiation oncologist works with other cancer doctors to determine how a course of radiation can be most effective of each patient’s needs. The radiation oncologist will prescribe the amount of radiation to be delivered and work with other members of the radiation team to ensure proper targeting and delivery. He or she will also oversee your radiation treatments on a regular basis.

Radiation Oncology Nurses

The radiation oncology nurses work collaboratively with the radiation oncologist, radiation therapists, and other cancer nurse specialists to care for you at the time of diagnosis and during treatment. They will explain the process of radiation therapy, and the possible side effects. They will assess how you are doing throughout the treatment and help the doctor manage any changes.

Radiation Therapists

Radiation therapists administer the daily radiation treatments under the doctor’s prescription and supervision. They maintain daily records of the treatments to help in the overall medical management. Radiation therapists receive special training and are required to have a special license.

Medical Physicist

Medical physicists are licensed by New York State after specialized training and have a doctorate or master’s degree. Medical physicists are key in helping the radiation oncologist plan and deliver the correct treatment. Their responsibilities also include the monitoring of the treatment machines with multiple precise measurements.


Dosimetrists work under the supervision of the medical physicist and carefully calculate the dose of radiation for each treatment plan. Today, dosimetrists use computers for planning and work closely with the physician to develop the best plan to destroy the tumor and avoid normal tissue. Dosimetrists are specially trained members of the team.

HealthAlliance Hospital
105 Mary's Avenue
Kingston, NY 12401
Phone: 845.338.2500

Get Directions »

Thomas A. Dee Cancer Center
111 Mary's Avenue
Kingston, NY 12401
Phone: 845.334.3015

Get Directions »