[Cytologic diagnosis of different histologic forms of lung cancer]

Parallel cytological and histological investigations in 511 patients with of the lung cancer confirmed the possibility of verification of a tumour form on the basis of cytological preparations. Determination of cancer forms is carried out on the basis of the same principle criteria which are used in a histological investigation. The first stage of diagnosis consists in search for cellular, structural and functional signs of epidermoid and glandular differentiation. In the absence of these, there are grounds to consider the diagnosis to be non-differentiated cancer with subdivisions into micro- and macrocellular variants. Squamous-cell carcinoma with cornification highly differentiated adenocarcinoma and non-differentiated microcellular cancer possess characteristic features ensuring a highly reliable-cytological diagnosis. Cytological diagnosis of squamous-cell cancer was correct in 95.3% of cases, that of non-differentiated microcellular cancer-in 87.1%, and that of glandular cancer-in 81.2% of cases. The majority of errors made in verification of squamous-cell and glandular cancer were made with respect to their poorly differentiated forms which have no reliable cytological characteristics. The last statement is also true with respect to non-differentiated macrocellular cancer of the lung.