Histogenesis of central lung cancer: cytological investigation.

Aim: To study the features of the bronchial mucosa lesion in relation to centrally growing lung cancer (LC) according to diagnostic fibrobronchoscopy in comparison with the results of cytomorphological data to determine the possible origin of tumor growth (histogenesis).

Patients And Methods: The data of fibrobronchoscopy and cytological findings based on the materials of 75 patients with a clinical diagnosis of LC were studied and compared. By the sum of the numerous cytomorphological features of epithelial cells and their components, the cells of the cylindrical epithelium and LC of various histological types were identified. The cells in bronchial smears and bronchial lavage were stained by Pappenheim and Papanicolau. Diagnostic material was examined by light microscopy.

Results: We have found that in a part of the patients (49%), the tumors with exophytic growth in the bronchus are covered with a cylindrical epithelium, which indirectly indicates the origin of cancer growth under the epithelial layer. In cytological preparations of 51% patients, cancer cells were found, which confirms the tumor invasion into the bronchial mucosa. In 48 (64%) patients, fibrobronchoscopy revealed that the examined bronchus was compressed from 50% to pinpoint width, evidencing that tumor growth develops from the outside, peribronchially.

Conclusion: The obtained data indirectly confirm the development of central LC from type II pneumocytes, which are found in the glands of the submucous membrane of the bronchus. However, it does not exlude the development of this type of LC from the basal cell of the bronchial epithelium.