The purpose of the research study is to develop a new, more sensitive, and less invasive test for diagnosing lung cancer at an earlier stage, when it can more easily be cured. The investigators hypothesize that certain genes are expressed differently in current and former smokers who have lung cancer, and this difference in gene expression may be a biomarker for lung cancer.

Allegro Diagnostics is funding this multi-center study to validate and extend a new diagnostic tool measuring global gene expression in airway epithelial cells obtained at routine bronchoscopy in suspect lung cancer patients. The test, which is highly sensitive and specific for lung cancer, measures the levels of expression of genes in cells brushed from the large bronchi during diagnostic bronchoscopy. Similar brushings of epithelial cells from the nose will be analyzed to determine if gene expression in these cells can be used as a screening tool in subjects who may have now or be at risk for developing lung cancer in the future.

Inclusion Criteria:

• Patients being evaluated for the diagnosis of possible lung cancer or "rule out lung cancer" and undergoing clinically indicated bronchoscopy
• All patients are required to be at least 21 years of age and be able to understand and sign the informed consent form
• Patient must be a current or former cigarette smoker

Exclusion Criteria:

• A pulmonary physician does not recommend that bronchoscopy be performed
• Inability to understand the written consent form and comply with requirements of the study
• History of prior primary lung cancer
• Immediately prior to bronchoscopy, the patient has been on a mechanical ventilator for >24 consecutive hours.

Patients of enrolled medical centers who are undergoing clinically indicated bronchoscopy for suspect lung cancer and who are current or former cigarette smokers.