Sputum Cytology in Screening Heavy Smokers For Lung Cancer

OBJECTIVES: Primary * Classify annual sputum samples cytologically in participants with or without airflow obstruction and a heavy smoking history. * Correlate sputum cytological atypia (moderate atypia or worse) with lung cancer incidence in these participants. * Correlate changes in sputum cytology (i.e., changes toward higher grades of atypia) with lung cancer incidence in these participants. Secondary * Determine other risk factors for lung cancer (e.g., diet, family history, smoking history, and medications) that may either confound or modify the association between sputum cytology and lung cancer risk in these participants. OUTLINE: Two 3-day pooled sputum samples are collected for 6 consecutive days from participants by the spontaneous cough technique for cytopathological evaluation. Participants also complete a risk factor questionnaire and undergo a pulmonary function test by spirometry and a blood draw. Participants complete a questionnaire updating smoking, vital, and lung cancer status and undergo sputum sample collection annually. Participants are informed of sputum cytology results. PROJECTED ACCRUAL: A total of 3,400 participants (2,900 with airflow obstruction and 500 without airflow obstruction) will be accrued for this study.