Non-small-cell lung carcinoma: tumor characterization on the basis of flow cytometrically determined cellular heterogeneity.

Some 150 tumor specimens from 49 patients with non-small-cell carcinoma of the lung (23 epidermoid, 14 adenocarcinoma, 12 large-cell carcinoma) and three with nonneoplastic lung disease were analysed for cellular DNA content by flow cytometry. Monodispersed cells were stained with ethidium bromide and mithramycin. Normal specimens and samples from patients with nonneoplastic disease constantly yielded a single cell population with diploid DNA content. Twenty of 23 epidermoid carcinomas exhibited one or more than one aneuploid subpopulation. Ten of 12 large-cell carcinomas were characterized by one aneuploid clone and 2/12 by two aneuploid clones. Adenocarcinoma exhibited multiclonal cell subpopulations (one to five aneuploid clones). Further information has been obtained on the differential presence of clones in various tumor areas and in infiltrated lymph nodes. These tumors appear characterized by a remarkable degree of cellular heterogeneity. The cytometric ploidy level(s) and the cell population multiclonal structure yield, in comparison with, and in addition to, pathology, indications of possible clinical interest. A correlation between the clonal DNA content and a prognostic parameter such as the tumor mass doubling time has been demonstrated.