Aneuploid DNA pattern in human pituitary adenomas

The DNA contents of 29 histologically and ultrastructurally benign pituitary tumours were analyzed with flow-cytofluorometry.--Cytogenetic malignancy, i.e., aneuploidy, was found in 12 cases, independent of endocrinological type of tumour. In 17 cases a diploid DNA content occurred. In aneuploid tumours varying percentage of cells in S-phase was found indicating different growth patterns. Aneuploid DNA pattern was often found in young patients with a short case history. Our findings indicate that analysis of cellular DNA content may reflect the biological properties of pituitary tumours, independent of morphologic characteristics and type of hormone secretion.