In the year 2001 there will be more than two hundred thousand cases of lung cancer diagnosed in the United States. This remains the most common cancer in men and women, and the cancer that kills more people in the United States than any cancer.

When lung cancer is diagnosed very early, the cure rates are extremely high, approaching 90%. However, unfortunately, only 15% of all patients diagnosed with lung cancer are found at the very earliest stages, where surgery is the most effective treatment. Therefore, the vast majority of patients will most likely be treated either with radiation therapy, chemotherapy, or a combination of the above.

The typical course of radiation therapy for lung cancer involves between two and six weeks of daily radiation treatments, Monday through Friday, given in a radiation oncology department. The treatment is usually given on an out-patient basis, and each treatment last only several minutes. The most common side effects from radiation treatments include fatigue, a sunburn skin reaction on the chest, and possibly a sore throat if the esophagus is irritated by the radiation.

Radiation therapy works by directing a radiation beam through the chest to the site of the tumor. High doses of radiation are able to destroy the tumor, and in some cases cure the patient of cancer. Several new treatment-planning modalities have been developed to make the radiation therapy more effective. By using a CT scan during the planning session, and recreating the chest in three-dimensions in the computer, the physician is able to accurately see the tumor, the normal lung tissue, and other critical structures including the spinal cord. By being able to optimally visualize the tumor, the physician can then direct the radiation beam more accurately toward the tumor sparing normal lung tissue and critical structures. One of the problems with lung cancer, is because the tumor is in the lung tissue, which moves with a person's respiration, the target volume (the tumor) is constantly moving up and down. In the past, in order to compensate for this movement, the radiation oncologist would need to direct the radiation beam at a larger volume, to include any region into which the tumor might move as a result of respiration. A recent breakthrough in technology has allowed us to take into account this respiratory movement, without increasing the area that need to be treated, and therefore limiting the dose to normal tissue. This technique is called respiratory gating and is a method by which the radiation machine treats in synchronization with the patient's respiration. This technology is similar to that used by the military. When a missile is fired at a target, the missile is launched only once the crosshairs have locked over the target. Similarly, the radiation beam is only turned on when the tumor is within the eye of the beam. A computer keeps track of the patient's breathing cycle, and only allows the radiation beam to turn on when it can lock on to the tumor. This very precise treatment technique therefore allows a higher dose of radiation to be given, because we are directing the radiation only to tumor, and limiting the dose to the normal surrounding tissues. Theoretically, this will allow for significantly fewer side effects and complications, and higher control rates for lung cancer. Saint Vincents Comprehensive Cancer Center, Department of Radiation Oncology, has successfully been using this new technology for the past two months. Currently, all eligible patients with lung cancers, as well as with other cancers in the upper abdominal area are being treated with this new technique.