DNA ploidy and cell phase in human pituitary tumors

The flow-cytofluorometric technique for nuclear DNA analysis was used in the study of 47 consecutive cases with pituitary tumors. The material consisted of 18 tumors secreting growth hormone (GH), 10 secreting GH and prolactin (PRL), 10 prolactinomas, 2 secreting thyroid-stimulating hormone (TSH), 2 secreting ACTH, and 5 were nonsecreting. An aneuploid DNA pattern occurred in 23 of 47 (49%) cases ranging from 1.4 to 3.6 N thus deflecting from the normal diploid 2N chromosome content of somatic nonreproductive cells. In four tumors two cell lines occurred, but one of them was always dominant, comprising 80% to 90% of all cells analyzed which totally amounted to 20,000 to 30,000 cells. The highest percentage of aneuploid tumors occurred in those with a concomitant secretion of GH and PRL (8 of 10, 80%). The percentage of diploid cells in tumors with an aneuploid nuclear DNA content was very low, 2.3 +/- 2.9% (+/- 0.65% SE). In 11 cases with aneuploidy, diploid cells were not detected. The mean age in patients with diploid and aneuploid tumors was rather similar in the different endocrinologic types of tumors.