Cytomorphological grading and Feulgen DNA-analysis of metaplastic and neoplastic bronchial cells.

Quantitative determinations of nuclear DNA were made on squamous metaplastic and neoplastic cells from sputum cytology specimens. The cellular material was processed by destaining diagnostic smears, restaining by the Feulgen method and relocating the cells for measurement. Adventitious leucocytes were used as internal controls. There was good correlation between increasing degree of aneuploidy as judged from DNA values, and increasing degree of morphologic nuclear atypia. The data indicate a progressive aberration from normality of nuclear DNA content in squamous metaplastic and neoplastic cells exhibiting a progressive degree of atypia. This implies that squamous bronchial carcinoma is preceded by sequential changes of the cellular composition which may be recorded by both quantitative DNA analysis and cytology.