Studies Show Promise in Treating Non-Small-Cell Lung Cancers

Lung cancer is the most common cause of cancer death in men and women. The major form of treatment is either chemotherapy, for small-cell lung cancers, or surgery, for other types.

It sometimes happens, however, that patients with non-small-cell lung cancers (such as squamous-cell carcinoma or adenocarcinoma) have inoperable disease or cannot be operated on for medical reasons such as poor lung capacity. In that case, radiation therapy is used as an alternative.

Except that using conventional radiation therapy -- standard x-ray external beam radiation -- can present significant and sometimes complicating problems. Normal lung tissue is very sensitive to radiation, even at relatively low doses, and must be avoided as much as possible.

The lungs are in close association with the heart and spinal cord; so much so that physicians want to limit radiation exposure of these organs to prevent future problems from developing. This is especially true in the case of the spinal cord, which, like the lungs, is very sensitive to radiation.

However, physicians at Loma Linda University Medical Center (LLUMC) in southern, California, have found a way to deliver high enough doses of radiation to be effective against lung cancer, while sparing normal tissue and nearby organs to a much greater extent than conventional radiation can. Proton beams, far superior to standard x-ray radiation beams, are not only highly conformable, but can also be made to focus precisely on targeted areas in the human body.

Two recent studies published in medical journals by Loma Linda investigators suggest that proton radiation therapy can overcome the main limitation of conventional radiation treatment for treating non-small-cell tumors of the lung. It is possible for Loma Linda physicians to deliver effective doses of proton therapy while sparing lung tissue that would be irradiated if conventional x-ray radiation therapy were used.

The studies found that higher doses of proton radiation was associated with a lower frequency of pulmonary injury, and of reduced severity, when compared to conventional radiation treatment. The studies also determined that because of their ability to deliver effective doses of radiation and yet reduce side effects, protons have enormous implications for the medical costs of treating lung cancer. Which means the costs of treating severe side effects are expected to be reduced for patients, providers, and the health-care system. 

Reduced side effects is probably the greatest benefit offered by proton beam radiation therapy. The proton beam has been compared to the surgeon's knife and often called "bloodless surgery." The proton beam also has a much sharper "edge" than conventional x-ray therapy, resulting in less "spill" of radiation into normal tissues. Protons deposit far less energy in normal tissues intervening between the skin surface and the target in the lung.

To learn more about proton therapy call 1-800-protons (776-8667) or log on to www.llu.edu/proton .

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