Media Contact: Kelli StauningTel. 310-423-3674 or 310-423-4767[email protected]
TORONTO, ONTARIO, CANADA (Embargoed until June 24, 2001 at 1:45 p.m., Eastern Standard Time) -- A new diagnostic imaging agent has been found to improve detection of lung cancer that has spread, enabling physicians to provide better treatment options for patients with lung cancer, according to Dr. Alan Waxman, Director of Nuclear Medicine and Co-Chairman of Imaging at Cedars-Sinai Medical Center. The new agent may also reduce the overall costs of patient care by eliminating unnecessary surgeries.
The study, presented at the 48th Annual Scientific Session of the Society of Nuclear Medicine, evaluated 45 patients with lung cancer to determine whether a non-invasive imaging agent recently approved by the Food and Drug Administration called Tc-99m Depreotide was more effective than a CT scan alone in detecting lung cancer that had spread. The investigators found that Depreotide was 30 percent more sensitive in detecting cancer that had spread to lymph nodes in the more central area of the chest called the pulmonary hilum and mediastinum.
"Our early results indicate that a Depreotide scan better characterized the tumor nodules seen on the patient's CT and also detected malignant tumors located in the more central areas of the chest with a higher degree of accuracy than demonstrated for CT alone, " said Dr. Waxman, lead investigator of the study.
Currently, radiologists use CT scans to characterize the single pulmonary nodule (SPN) -- or an abnormal collection of cells in the lung that may or may not be cancerous. CT scans also show abnormal lymph nodes that might be present in the central areas of the chest. But CT scans often fail to detect smaller tumors that may have spread beyond the lung and may not distinguish cancerous tumors from those that are benign. Consequently, treatment may be based on the results of the CT scan alone. For this reason, unnecessary or inappropriate surgeries may be performed.
To determine whether images obtained using the Depreotide agent were better able to detect these harder to find tumors in the chest, patients were given an injection of Tc-99m Depreotide and images of the lungs were taken with a nuclear medicine camera. The scans were taken four weeks prior to biopsy and compared to the pathology results of the tumor samples taken during the surgical procedures. Depreotide's sensitivity to detect -- or its specificity to rule out cancer was calculated for the presence of SPN's as well as for the detection of cancer that had spread to the lymph nodes in the central chest.
The investigators found that the sensitivity of Depreotide to detect SPN's was 94 percent, while its specificity or ability to rule out cancer was 78 percent. For the hilum and mediastinum (more central areas of the chest), the site sensitivity of depreotide was 100 percent and the specificity 80 percent. False positive test results occurred in 22 percent of the patients, which indicated that cancer was present when no pathological evidence of cancer was found. The false-positive results occurred when a patient had infection or inflammation of the lung including pneumonia or reactive cells of the lymph nodes caused by prior inflammation or infection.
Alternatively, the CT scans were 60 percent sensitive for detecting spread to central chest nodes and 70 percent specific in ruling out cancer.
"Because Depreotide is able to detect these harder to find tumors, surgeons will have information to help them determine the extent of a patient's disease and to know which patient is likely to benefit from surgery to remove the cancer," said Dr. Waxman, adding that overall medical costs could be reduced.
Lung cancer is the leading cause of cancer death for both men and women in the United States, taking the lives of more people with colon, breast and prostate cancers combined. In the year 2000, there were 169,500 new cases of lung cancer diagnosed in this country. Early detection and accurate diagnosis are critical to managing a patient's treatment and improving long-term survival rates.
Cedars-Sinai Medical Center is one of the largest non-profit academic medical centers in the Western United States. For the fifth straight two-year period, Cedars-Sinai has been named Southern California's gold standard in health care in an independent survey. Cedars-Sinai is internationally renowned for its diagnostic and treatment capabilities and its broad spectrum of programs and services, as well as breakthrough in biomedical research and superlative medical education. The Medical Center ranks among the top seven non-university hospitals in the nation for its research activities.
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For media information and to arrange interviews, please contact Kelli Stauning at 310-423-3674 or via e-mail at [email protected].
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