Jul 8, 1999
A painless, 20-second test could save more than 100,000 lives annually in the United States by detecting lung cancer at an early, curable stage, say researchers at Weill Medical of Cornell University and New York Presbyterian Hospital (New York Weill Cornell Center). Their dramatic findings, published in the July 10th issue of The Lancet, show that low-dose CT (low radiation dose computed tomography) can find lung tumors long before they appear on traditional chest x-rays.
Lung cancer is the leading cause of cancer mortality in the United States. More women and men die of lung cancer than from breast, prostate, and colorectal cancer combined. This year, more than 160,000 Americans will die from this terrible disease, which is usually diagnosed only after it has advanced too far to be stopped.
"Lung cancer is deadly because we never had a good way to find it early. Now we do," said Claudia I. Henschke, M.D., Ph.D., Principal Investigator of the study, and Professor of Radiology and Division Chief of Chest Imaging at the New York Weill Cornell Center of New York Presbyterian Hospital. "CT screening transforms the prognosis for lung cancer, just as mammography did for breast cancer and the PAP test did for cervical cancer."
The results come from the Early Lung Cancer Action Program (ELCAP), the first major study of baseline screening by low-dose CT in 1,000 smokers and former smokers age 60 and older. The CT test detected 23 early-stage lung cancers. Only 4 of the tumors were visible on chest x-ray, the standard diagnostic imaging technique. None of the patients had any symptoms of lung cancer.
Lung cancer tumors typically are about the size of an orange by the time they’re discovered. In contrast, most of the lesions detected on CT were no bigger than a grain of rice. "The current five-year survival rate for lung cancer is only 14 percent. But that could soar to 80 percent if all smokers and ex-smokers received annual CT exams and early treatment," commented Dr. Henschke.
The low-dose CT used for screening requires less than 20 seconds of scanning time and entails only slightly more radiation than a chest x-ray. Moreover, this diagnostic test is affordable, at a cost relative to the average chest x-ray. Follow-up tests track suspicious nodules to avoid unnecessary biopsies.
Along with Dr. Henschke, the New York Weill Cornell research team includes David F. Yankelevitz, M.D.; Olli S. Miettinen, M.D., Ph.D.; Daniel M. Libby, M.D.; Mark W. Pasmantier, M.D.; June H. Koizumi, M.D.; Nasser K. Altorki, M.D.; and James P. Smith, M.D. This study was done in collaboration with New York University (NYU) Medical Center researchers.