Advanced Radiation

At Willamette Valley Cancer Institute and Research Center (WVCI), we believe technology is a crucial part of providing the best care possible. Targeted treatment starts by learning as much as we can about patients and their diseases and continues with treatments that maximize effectiveness and minimize side effects. Thanks to advances in radiation therapy, we are able to locate tumors with astounding accuracy and deliver treatment where cancers are most vulnerable. These technologies are successfully making the fight against cancer more focused than ever. The result for patients is that treatments may be completed in a shorter amount of time, with less discomfort and more encouraging results.

As a member of the Radiation Therapy Oncology Group (RTOG), WVCI is helping to develop new forms of therapy as part of the largest radiation research group in the country. As radiation technologies continue to develop, WVCI continues to add new types of radiation therapies to its arsenal of cancer fighting treatments.

Radiation therapy may be delivered externally or internally. External radiation delivers high-energy rays directly to the cancer from a machine outside the body. Internal radiation, or brachytherapy, is the placement of a small amount of radioactive material (seeds) in or near the cancer.

Brachytherapy

Internal radiation is known by a number of names, including "brachytherapy," "seeds," or "implants." These terms refer to treatment in which radioactive material is placed directly into or near the cancer. Brachytherapy may be used to provide an additional boost of radiation to an area also being treated with external radiation therapy, or may be used as the only type of radiation therapy.

WVCI uses temporary brachytherapy, or high dose rate (HDR) brachytherapy. With HDR brachytherapy, the radioactive material is inserted for a specified period of time and then removed before the patient goes home. HDR brachytherapy is performed on an outpatient basis, that is, admission to the hospital is not required. Brachytherapy has proven to be useful in the treatment of several different types of cancer, including prostate, breast, cervix, uterus and vagina.

Prostate Brachytherapy

An excellent alternative to external beam radiation or surgery for men with prostate cancer that has not spread beyond the prostate gland, brachytherapy uses ultrasound guidance to place small plastic catheters directly into the prostate. A radiation seed then travels through the catheters and delivers a high dose of radiation to the prostate. Brachytherapy allows radiation oncologists to precisely control where the radiation dose is deposited, limiting dose to surrounding normal tissues such as the bladder and rectum.

Breast Brachytherapy

Breast brachytherapy is an alternative to traditional EBRT for women who choose breast conservation rather than a mastectomy. Breast conservation therapy involves removing the tumor in a procedure called a lumpectomy and is followed by radiation therapy to reduce the likelihood of recurrence. Traditional EBRT following a lumpectomy consists of five to six weeks of radiation treatment, five days per week. With breast brachytherapy, only the area surrounding where the cancer was prior to surgery is treated. The prescribed dose of radiation is administered during a five-day course of therapy.

Because of the relatively short duration of the treatment course, breast brachytherapy is an attractive option for women who choose lumpectomy over mastectomy, but do not wish to undergo six weeks of EBRT. Also, breast brachytherapy treats less normal tissue than whole breast radiation, so there tend to be fewer side effects.

MammoSite is one way to deliver breast brachytherapy. The procedure involves inserting a deflated balloon into the cavity where the tumor was removed. An applicator shaft, or catheter, connects the balloon to the outside of the breast. The balloon is filled with saline, and both the balloon and the catheter remain in place during the time the woman is undergoing treatment. The radiation therapy is performed on an outpatient basis in a five-day-long, twice-per-day sequence of treatments. During the treatment, a radioactive "seed" is inserted into the catheter within the balloon in an exact dose, minimizing radiation exposure to the rest of the breast, skin, ribs, lungs, and heart. No source of radiation remains in the patient's body between treatments or after the final procedure. The catheter and balloon are removed after the final procedure.

External Beam Radiation Therapy (EBRT)

EBRT is given via machines called linear accelerators, which produce high-energy external radiation beams that penetrate tissue and deliver the radiation dose deep in the areas where the cancer resides. These modern machines and other state-of-the-art techniques have enabled radiation oncologists to significantly reduce side effects while improving the ability to deliver radiation.

EBRT is typically delivered on an outpatient basis for approximately 6 to 8 weeks. EBRT begins with a planning session, or simulation, during which the radiation oncologist places marks on the body and takes measurements in order to line up the radiation beam in the correct position for each treatment. During treatment, the patient lies on a table and is treated with radiation from multiple directions. The actual area receiving radiation treatment may be large or small, depending on the features of the cancer. Radiation can be delivered specifically to a cancer, or encompass the surrounding area, including the lymph nodes.

Intensity Modulated Radiation Therapy (IMRT)

IMRT is an advanced form of external beam radiation therapy that has been used at WVCI for many years and is commonly used to treat breast, prostate, lung, head and neck and many other types of cancer. IMRT allows doctors to customize the radiation dose by modulating, or varying, the amount of radiation given to different parts of the area being treated. The radiation intensity is adjusted with the use of computer-controlled, moveable "leaves" which either block or allow the passage of radiation from the many beams that are aimed at the treatment area. The leaves are carefully adjusted according to the shape, size, and location of the tumor. As a result, more radiation can be delivered to the tumor cells while less is directed at the normal cells that are nearby. Unlike standard radiation techniques that allow only a constant flow of radiation from each beam, IMRT allows radiation oncologists to "paint" the radiation dose.

Image-guided Radiation Therapy (IGRT)

In the past, conventional radiation involved a mapping session, or simulation, during which marks were made on the skin and x-rays were taken to line up the radiation fields. Variations due to weight loss or normal movement related to breathing or bladder filling required that a certain amount of surrounding normal tissue be treated as well.

Conventional radiation is very safe and effective. When the radiation fields are designed, they are created in such a way that potential changes are accounted for. IGRT is a new approach to delivering radiation therapy that allows for the most accurate delivery of radiation to the target tissue. With IGRT, a mapping session or simulation is still performed.

IGRT differs from conventional radiation in that prior to each treatment, an image of exactly where the cancer is in the body is obtained. A computer compares images taken at the time of treatment to images taken during the planning phase and the radiation fields are lined up with the cancer itself, rather than relying on skin marks. Through this process, IGRT is able to account for changes in the patient's body or position that may shift the exact location of the cancer. This allows increased accuracy of very complex treatment approaches.

IGRT is best used for cancers that may move a lot with normal changes in positioning or breathing motion, such as prostate, lung, liver and kidney. IGRT is also an excellent option for cancers that are very close to extremely critical organs. For example, cancer of the bones of the spine is very close to the spinal cord and pancreas cancer is often close to the spinal cord, kidneys and liver. For these types of tumors, IGRT may be the best type of radiation.

As a result of the IGRT technology, smaller radiation fields can be used because the cancer targeting is more precise. Smaller fields mean fewer side effects and less severe side effects. IGRT also allows for the delivery of higher doses of radiation, which may improve the chances of controlling or curing cancer. Bigger doses of radiation with each treatment can also mean fewer total treatments. IGRT may be used in combination with IMRT for ultra-precise radiation treatment delivery.

The advantages of IGRT include:

More precise radiation delivery
Fewer side effects
Less severe side effects
Potentially fewer treatments
Better cancer control

WVCI was the first treatment center in the area to offer IGRT and we now offer CAT-scan, or CT-scan, based IGRT. This allows us to continue to offer our patients the best radiation treatment possible.

Stereotactic Radiosurgery (SRS)

Stereotactic Radiosurgery (SRS) allows non-invasive treatment of brain tumors, arteriovenous malformation, and other selected conditions. It is an outpatient treatment that delivers a high dose of radiation to a highly defined target. Treatments can be prescribed to deliver the total dose of radiation in a single treatment or in a fractionated manner over a course of several weeks.

Gamma Knife stereotactic radiosurgery is offered through WVCI and our partnership with PeaceHealth. The Gamma Knife machine is located at Sacred Heart University District.

Body radiosurgery, a technique similar to Gamma Knife stereotactic radiosurgery, will be available in the coming months. The technology, which involves the use of a CAT scan before each treatment, will allow us to treat lung, liver, spine, prostate and other types of cancer using the best radiation technology available.