A 70-year-old man has smoked for years despite a chronic productive cough. One day, he notices blood in his sputum and goes to see his physician. A chest x-ray reveals a mass in the left lung, which is biopsied during a fiberoptic bronchoscopy. Assuming that this patient's cancer is etiologically related to his smoking, which of the following diagnoses are most likely to be returned by the pathology laboratory?

Smoking does not increase the risk of all types of lung cancers to the same degree. Oat (small) cell carcinoma has a very strong association with smoking, with only 1% of cases occurring in nonsmokers. Squamous cell carcinoma is also strongly associated with smoking, because smoking predisposes for squamous metaplasia, a precancerous condition. The association of smoking with bronchogenic adenocarcinoma and with bronchioloalveolar carcinoma is much weaker.