NUCLEAR-DNA PATTERNS IN ADRENAL-CORTEX PROLIFERATIVE LESIONS

In cortical adrenal gland tumours there are discrepancies between morp hological criteria for malignancy and biological behaviour. This makes it difficult to select the appropiate treatment. We have studied morp hometric and DNA densitometric features of 24 adrenal proliferative le sions (hyperplasia, adenoma, and carcinoma) by means of slide cytometr y. All variables have been correlated with pathological diagnosis. The samples were selected from paraffin-embedded tissue, and representati ve lesions were Feulgen stained. Densitometric study showed aneuploid cell lines in every carcinoma, 5 of 8 adenomas, and 5 of 10 hyperplast ic lesions. Both DNA nuclear content (mean ploidy of 2.11 c, 2.41 c, a nd 3.05 c) mean nuclear area (average of 31.26 mum2, 35.92 mum2,and 42 .39 mum2) showed progressive increase from hyperplasia to adenoma, and carcinoma. Mean shape factors were lowest in adenomas (1.69) and high est in carcinomas (1.82). Those karyometric variables which showed sta tistically significant differences (p < 0.05) among diagnostic groups were included in a stepwise three-way discriminant analysis. Only thre e parameters, shape factor (p = 0.0008), mean ploidy (p = 0.0012), and adrenal weight (p = 0.0055) persisted as independent predictive facto rs. Using the three variables selected by discriminant analysis on our cases, 100% of the adenomas were correctly classified, 83 % of the ca rcinomas, and 80% of the hyperplasias. Tumour weight and nuclear shape factor differentiated adrenal cortex adenoma from carcinoma, while me an ploidy distinguished adrenal cortical hyperplasia from carcinoma. N uclear pleomorphism (shape factor) and DNA-ploidy are the most importa nt nuclear features in predicting the biological course of proliferati ve adrenal cortex lesions, although by themselves they are not bona-fi de discriminators.