The primary objective of this study is to determine if more diagnoses of lung cancer are obtained from the cytological evaluation of sputum expectorated following a single inhaled dose of UTP compared to sputum expectorated following a single inhaled dose of placebo in patients suspected of having lung cancer.

Inclusion Criteria:

• be suspected of having primary lung cancer based upon chest radiograph(s), CT scan(s), or PET scan(s) and with symptom, risk profile, or history suggestive of malignancy
• have FEV1 greater than or equal to 40% predicted normal for age and height

Exclusion Criteria:

• have obtained a confirmed diagnosis for the current suspicious lung tumor
• have been treated for the current, suspicious tumor except in cases in which the current lesion is the recurrence of the same tumor (same location) for which treatment was administered no less than 180 days prior to screening
• have undergone a bronchoscopic examination or pulmonary fine needle aspiration biopsy within 4 days prior to dosing, or have undergone sputum induction within 3 days prior to dosing