DNA flow cytometry of hereditary and sporadic paragangliomas (glomus tumours)

Paragangliomas (glomus tumours) are benign, hypervascular tumours which in general are treated by surgical excision. The indication for treatment of these often slow-growing tumours needs additional criteria for predicting tumour progressiveness. For this reason the nuclear DNA content of 99 paragangliomas, 65 of them originating from patients with a positive family history, was analysed by flow cytometry. Unequivocal evidence of DNA aneuploidy was found in 37% of these clinically and histologically benign tumours, the average duration of follow up amounting to at least 10 years. The DNA index of the aneuploid tumours ranged from 0.90 to 2.03. No correlation was found between DNA ploidy and familiality or between DNA content and clinical criteria indicative of tumour progression, which means that DNA ploidy of these tumours cannot serve as a predictor for an expected growth pattern or familiality. DNA aneuploidy in hereditary and sporadic paragangliomas is not clinically related to malignancy, but indicates that these tumours are true neoplasias cytogenetically.