HISTOPATHOLOGY OF LUNG-CANCER

Lung cancer is a complex problem because there are a number of different histological cell types. Those commonly grouped as bronchogenic carcinoma (epidermoid carcinoma, adenocarcinoma, large cell undifferentiated carcinoma, small cell carcinoma, and adenosquamos carcinoma) account for more than 90% of the new cases and the deaths each year. The natural history of bronchogenic carcinoma suggests that many years pass while the cancer evolves from a precancerous change in the bronchial mucosa, to undetectable microscopic cancer, to preclinical asymptomatic cancer and finally into a full symptomatic cancer, the phase of most lung malignancies in the tissue at diagnosis. Therefore, students of the aetiology of this disease must consider what has happened to patients 5–20 years before lung cancer is diagnosed. © 1990 Oxford University Press.