Advances in Therapeutic Radiology
The field of radiology continues to make gains in knowledge and technology. Newer
methods are being tested to find better treatments for cancer and other conditions
treated with radiation.
What are some types of advanced therapies?
Some newer radiation therapies are:
Radiation and chemotherapy in combination
Radiation may improve the effects of chemotherapy. In turn, chemotherapy may improve
the effects of radiation. Protocols are being develops to find the most effective
use of chemotherapy and radiation.
This method uses external beam radiation therapy or other types of radiation during
surgery to treat certain cancers. The benefit of this method is that less tissue is
exposed to radiation. The target area can be directly viewed, and a more effective
dose of radiation may be used. The use of intraoperative irradiation, along with surgery,
external beam therapy, or chemotherapy, has been shown to improve the outcome of cancer
treatment in some cases.
Stereotactic irradiation (radiosurgery)
Stereotactic irradiation is the use of a single high dose of radiation. Radiation
is sent into the diseased tissue with very narrow beams of radiation. The two main
forms of stereotactic irradiation are linear acceleration and the gamma knife. This
method cut the length of hospital stays and the costs for certain brain cancers and
Particle radiation therapy
Particle radiation therapy uses higher-energy radiation particles in cancer therapy.
Types of radiation particles used in radiation therapy include neutrons, protons,
ions, and antiprotons.
Proton therapy is the most widely used type of particle therapy. Fast neutron therapy
may be used in the treatment of certain inoperable or recurrent tumors. There are
only a few centers in the U.S. that offer this treatment.
Antiproton therapy is the newest type of particle radiation therapy under study. It
has promise for use in radiosurgery techniques.
Internal hadron therapy is another type of particle radiation therapy. One example
of this type of therapy is boron neutron-capture therapy. A boron compound is given
to the person by injection. The boron builds up in the tumor or cancerous tissue.
A reaction occurs in the tumor when a beam of neutrons is sent into the tumor, destroying
the cancerous cells. The advantage of this method is that it can be used to treat
Three-dimensional (3D) conformal radiation therapy
Before the development of computed tomography (CT), exact targeting of a lesion or
tumor for radiation therapy was difficult. CT provided a 2-dimensional means of viewing
the treatment area. However, a 3D view is needed to define all borders of the lesion
or tumor for the most precise treatment planning.
Intensity-modulated radiation therapy (IMRT)
Similar to 3D conformal radiation therapy, intensity-modulated radiation therapy,
or IMRT, uses varying intensity within single radiation beams to minimize the amount
of radiation to normal tissues around the area being treated.
Radioimmunotherapy uses antibodies "tagged" with a cancer-killing substance. These
tagged antibodies recognize tumor cells and bind with them, thus bringing the cancer-killing
drug directly to the tumor tissue. The tagged antibodies may be given directly into
an artery, under the skin, or directly into a body cavity such as the uterus.
One advantage of this method is that it may be used to treat cancer that has spread
that is not visible by diagnostic means. This helps eliminate the spread of the disease.
Cyberknife is a non-invasive way to treat both cancerous and non-cancerous tumors,
as well as other health problems. It sends targeted, high-dose radiation to tumors,
reducing exposure to the nearby healthy tissue. The components include a robotic arm
and a tracking system that is used to reach tumors or problems in difficult regions
and from any direction.