Automatic Cell Identification and Enrichment in Lung Cancer III. Light Scatter and Two Fluorescence Parameters

Two physical parameters were investigated to automatically recognize cells in sputum from human squamous cell carcinoma of the lung and to separate them for preparation by the Papanicolaou methods, for human interactive identification and for automated high resolution image analysis. The two parameters, O.5_15.00 fo��ard argon-ion laser light scatter to estimate total cell size and 546 nm Acridine orange fluorescence to approximate total cell DNA content, were measured in a flow-through fluorescence activated cell sorting system. Enrichment for neoplastic cells in three cases of squamous cell carcinoma of the lung averaged 7.8fold over the original sputum when only green fluorescence was used and 10.5-fold using green fluorescence and forward light scatter. The average enrichment for neoplastic cells was 65.6-fold relative to polymorphonuclear deenrichment. With the current catastrophic rise of the occurrence of lung cancer in the general population and in industrial workers, and with the effectiveness of early cytologic detection of bronchogenic squamous cell carcinoma (epidermoid carcinoma), the potential demand for cytologic screening of populations at high risk is enormous. The objectives of the work presented in this article are to assess the feasibility of an automated system for the detection of human lung cancer, to define valuable parameters for machine assessment of malignant biologic behavior and to determine those factors necessary to preserve cell morphology. This report evaluates featames of narrow-angle forward light scatter related to cell size, and green fluorescence of Acridine orange (AO) related to total cell DNA content. Later reports will deal with RNA, proteins and additional parameters (3,4).