The field of radiation oncology is a steadfast contender in the fight against cancer. Technological advancements in imaging, treatment planning and treatment delivery are tremendously improving patient outcomes. More targeted radiotherapy is letting patients of all ages live a more normal life during and after the course of treatment and most importantly, improving outcomes.
Last June, the nation's leading cancer organizations - the American Cancer Society, the Centers for Disease Control and Prevention, the National Cancer Institute, and the North American Association of Central Cancer Registries - released its "Annual Report to the Nation on the Status of Cancer, 1975 - 2001" that brought good news. It said Americans' risk of getting and dying from cancer continues to decline and survival rates for many cancers continue to improve. "The new data reflects progress in prevention, early detection and treatment," the report stated.
To better understand "progress" in the fight against cancer, still the second leading cause of death in the United States, examine a segment of oncology that physicians have utilized for more than 100 years to treat cancer: radiation therapy. Today, when utilized alone or in combination with other therapies, radiotherapy is used to treat more than 60 percent of all cancer patients.
Radiation therapy has undergone a number of technological advancements in the past decade, namely in its ability to better target cancer and avoid surrounding healthy tissue. Intensity modulated radiation therapy (IMRT) is seen as state of the art and advancements in image guidance techniques are complementing both IMRT and 3D conformal radiation therapy (3D-CRT). Multi-modality cancer centers are redefining treatment plans with smaller margins. And informatics is paving the way for filmless/paperless environments where staff members can utilize PCs and mobile computing devices to enter and access critical patient data at the point of care.
As the NCI works to achieve its goal to eliminate suffering and death due to cancer by 2015, researchers and physicians are dedicated to furthering the clinical spheres of radiation oncology - from screening and diagnosis, through treatment and follow-up.
IMRT: More than hope
IMRT's precision offers patients the ability to lead a more normal life during and after the course of treatment.
The IMRT buzz began in the early 1990s when early implementers used it to treat prostate and head and neck cancers. Current statistics show that 38 percent of radiation oncology sites offer IMRT, up from 4 percent in 1998, according to a 2003 IMV census. Disease sites now targeted include the central nervous system, gastrointestinal malignancies, lung cancer and brain tumors, particularly in children.
The hallmark of IMRT is its ability to allow a higher dose of radiation to permeate the tumor while avoiding sensitive structures, thus reducing side-effects. The technology combines computer-generated images and inverse treatment planning software to deliver a tightly focused radiation beam that matches the 3D shape of the tumor. Oncologists modulate the intensity of pencil-thin beams of radiation to combat the toughest of cancers, usually those adjacent to - and tightly intertwined with - complicated structures.
A pediatric brain tumor called a medulloblastoma can be treated with radiation. IMRT can prevent severe hearing loss, which has been a common complication of treatment. A patient with reoccurring cancer in and around the spine that already underwent some form of prior radiation can be treated with IMRT, too. For incidences of cancer in a woman's left breast, radiation can be aimed away from the heart and lung.
Varian Medical Systems, North American Scientific, Elekta and Siemens Medical Solutions are leaders in IMRT technology. The University of Nebraska Medical Center (UNMC) in Omaha, Neb., uses IMRT technology from Siemens to treat prostate and head and neck cancers. Forward-planning IMRT is used for the treatment of lymphomas and breast cancer. "In treatment of the prostate, certainly IMRT has allowed us to give radiation doses that are much more likely to be curative in the long run, but also decrease side effects," says Charles Enke, MD, chairman and professor for UNMC's department of radiation oncology.
The department operates a total of four linacs: three for IMRT and one for 3D-CRT, Enke says. One of the four rooms is equipped with a Novalis Shaped Beam Surgery