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Chapter 085. Neoplasms of the Lung (Part 6)

Diagnosis and Staging Screening Most patients with lung cancer present with advanced disease, raising the question of whether screening would detect these tumors at an earlier stage when they are theoretically more curable. The role of screening high-risk patients (for example current or former smokers 50 years of age) for early stage lung cancers is debated. Results from five randomized screening studies in the 1980s of chest xrays with or without cytologic analysis of sputum did not show any impact on lung cancer–specific mortality from screening high-risk patients, although earlier-stage cancers were detected in the screened groups. These studies have been. | Chapter 085. Neoplasms of the Lung Part 6 Diagnosis and Staging Screening Most patients with lung cancer present with advanced disease raising the question of whether screening would detect these tumors at an earlier stage when they are theoretically more curable. The role of screening high-risk patients for example current or former smokers 50 years of age for early stage lung cancers is debated. Results from five randomized screening studies in the 1980s of chest x-rays with or without cytologic analysis of sputum did not show any impact on lung cancer-specific mortality from screening high-risk patients although earlier-stage cancers were detected in the screened groups. These studies have been criticized for their design and statistical analyses but they led to current recommendations not to use these tools to screen for lung cancer. However low-dose noncontrast thin-slice helical or spiral CT has emerged as a possible new tool for lung cancer screening. Spiral CT is a scan in which only the pulmonary parenchyma is examined thus negating the use of intravenous contrast and the necessity of a physician being present at the exam. The scan can usually be done quickly within one breath and involves low doses of radiation. In a nonrandomized study of current and former smokers from the Early Lung Cancer Action Project ELCAP low-dose CT was shown to be more sensitive than chest x-ray for detecting lung nodules and lung cancer in early stages. Survival from date of diagnosis is also long 10-year survival predicted to be 92 in screening-detected stage I NSCLC patients . Other nonrandomized CT screening studies of asymptomatic current or former smokers also found that early lung cancer cases were diagnosed more often with CT screening than predicted by standard incidence data. However no decline in the number of advanced lung cancer cases or deaths from lung cancer was noted in the screened group. Thus spiral CT appears to diagnose more lung cancer without improving .