Objective To investigate the relationship of DNA contents and S phase fraction (SPF) to the clinicopathologic characteristics and CT signs in non small cell lung carcinoma (NSCLC), and to make a further understanding of the biologic behavior of lung carcinoma.Materials and Methods DNA contents and SPF were measured by flow cytometry (FCM). A correlative study of CT signs and FCM in 39 cases with NSCLC was made. Results (1) DNA index (DI) and SPF of NSCLC were significantly higher than that of para tumorous tissues and normal lung tissues. In normal lung tissues only diploidy could be found. Aneuploid tumors showed higher SPF than diploid tumors did. (2) The TNM staging and pathologic grading carried significant associations with DI and SPF of NSCLC. (3) DI and SPF of tumors with a diameter over 3cm were higher than that of tumors with a diameter under 3cm. Higher DI and SPF were also found in the tumors with the signs of short spicules, deep lobulations and spinous processes, and with hilar or mediastinal lymph node enlargement. Conclusion DNA ploidy and SPF are closely related to the proliferative activity of NSCLC. As CT signs of NSCLC are in association with DNA contents which is concerned with the tumorous biologic behavior, CT manifestations can be used to infer indirectly the tumor’s malignancy and patient’s prognosis.
