Abstract
Biopsies from pituitary tumours in 8 patients were analysed with DNA flow-cytofluorometry immediately after surgery and after organ culture. Good agreement was found between the degrees of ploidy and of the relative proportions of cells in different phases of the cell cycle, indicating a good stability and reproducibility of pituitary tumour explants in vitro. Analysis of DNA content indicated a homogeneous cell population in tumours before and after explantation. No apparent correlation was observed between hormone secretion rate in diploid and aneuploid tumours, respectively, and DNA characteristics.