Paragangliomas: neuroendocrine features and cytometric DNA distribution patterns. A clinico-pathological study of 22 cases.

Paragangliomas from 22 patients with extraadrenal tumours of this type were studied. Neuroendocrine features were examined using immunohistochemical techniques. Twenty-two antisera raised against neuroendocrine "markers", regulatory peptides, serotonin and intermediate filament proteins were studied in this group and cytometric DNA assessments were made by means of image cytometry. One normal and 5 hyperplastic carotid bodies were used as controls in the DNA cytometric investigations. Clinical and/or histopathological evidence of "malignancy" was present in 5 cases. The tumour cells showed heterogeneity with regard to their expression of different peptides, and the immunohistochemical analyses did not permit differentiation between benign and malignant paragangliomas. An euploid nuclear DNA distribution pattern was found in all controls and in 17 of the tumours; all except 1 were clinico-pathologically benign. An aneuploid DNA pattern was observed in 5 of the cases and some malignant features were present in 4 of these cases. DNA data may give further information apart from that obtained from the histopathological findings which may be of value in predicting the biological behaviour of this tumour type.