Flow cytometric analysis of primary lung carcinomas and their lymph node metastases.

Specimens of primary lung carcinomas and lymph node metastases from the same 18 patients were investigated by means of flow cytometry. The number of DNA stemlines, DNA indices, the proportion of diploid cells in the tumors and the distribution of the cell cycle phases were compared. In 10 patients DNA stemlines and DNA indices were identical in primary tumors and metastases. In two cases the DNA indices were doubled in metastases. In 6 cases the primary tumors contained two abnormal DNA stemlines and their metastases contained only one aneuploid stemline. Gross differences between primary tumors and lymph node metastases with regard to the proportion of cell cycle phases could not be found. The large variation between primary tumors and lymph node metastases with regard to DNA stemlines indicates that flow cytometric analysis of lymph nodes gives only limited information about the primary tumors.