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Numerous journals weighed in on the pros and cons of CT screening for lung cancer in high risk patients. The idea of a series of three CT scans seems overly expensive and an over dose of radiation considering the number of false positives. A review in the Resident e-Bulletin of the NEJM
the teaching topic reports the article by M.K. Gould in the November 6th issue: NEJM, 371, 1813-1820 outlines the following.
Lung cancer has an 18% 5 year survival rate and early detection would help. The National Lung Screening Trial (NLST) consisted of 50,000 patients from 33 centers. Low-dose CT was compared with chest X-ray reporting 20% fewer deaths in the CT group, 247 vs. 309 for 2 year follow up. If valid statistically, that would be 3 deaths per 1000 saved.
The screening produced 39% positive reports, 95% of which proved false, however. The author suggested that the resulting additional CT scans and invasive procedures produced few complications: 2% from needle biopsy, 4% by bronchoscopy, and 4% from surgery. 73% of the needle biopsies and bronchoscopies were negative and 24% of the surgeries were benign. Only 1% of these invasive procedures experienced complications, 20% of whom did not have lung cancer. (approximately 0.2% complication rate for non-cancer)
Twenty years ago, our diagnostic routine (Swedish Hospital IM Denver) for 30 and more pack a day smokers with a cough was bronchoscopy, bronchial brushings, culture and chest X-ray. With the low complication rate for bronchoscopy in non malignant patients, why would one choose the overly expensive three CT screening with it's radiation exposure and 95% false positive rate when a low risk and relatively inexpensive bronchoscopy yields more definitive results? It does become a question of sensitivity, however. One would have to re-examine the claimed 20% reduction in 2 year mortality and apply the same if not better trial for the sensitivity of fiber-optic bronchoscopy and bronchial brushings in the early detection of bronchial genic carcinoma. One would be dependent on conventional PA and Lateral for the detection of non bronchial genic CA.
Lung cancer has an 18% 5 year survival rate and early detection would help. The National Lung Screening Trial (NLST) consisted of 50,000 patients from 33 centers. Low-dose CT was compared with chest X-ray reporting 20% fewer deaths in the CT group, 247 vs. 309 for 2 year follow up. If valid statistically, that would be 3 deaths per 1000 saved.
The screening produced 39% positive reports, 95% of which proved false, however. The author suggested that the resulting additional CT scans and invasive procedures produced few complications: 2% from needle biopsy, 4% by bronchoscopy, and 4% from surgery. 73% of the needle biopsies and bronchoscopies were negative and 24% of the surgeries were benign. Only 1% of these invasive procedures experienced complications, 20% of whom did not have lung cancer. (approximately 0.2% complication rate for non-cancer)
Twenty years ago, our diagnostic routine (Swedish Hospital IM Denver) for 30 and more pack a day smokers with a cough was bronchoscopy, bronchial brushings, culture and chest X-ray. With the low complication rate for bronchoscopy in non malignant patients, why would one choose the overly expensive three CT screening with it's radiation exposure and 95% false positive rate when a low risk and relatively inexpensive bronchoscopy yields more definitive results? It does become a question of sensitivity, however. One would have to re-examine the claimed 20% reduction in 2 year mortality and apply the same if not better trial for the sensitivity of fiber-optic bronchoscopy and bronchial brushings in the early detection of bronchial genic carcinoma. One would be dependent on conventional PA and Lateral for the detection of non bronchial genic CA.
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