Genetic Heterogeneity of Benign Thyroid Lesions

Abstract

The present series includes 75 thyroid lesions (38 goiters, 30 adenomas, 3 follicullo‐papillary encapsulated carcinomas and 4 normal thyroid) that were studied by static and flow cytometry. Four cases were also analyzed by in situ hybridization (centromeric probes for chromosomes 1 and 17) and 10 cases by G‐banding cytogenetics. Results demonstrate a polymorphysm and genetic instability in the thyroid tissue that may be related to the spontaneous polyploidization of their cells. The most consistent finding in cytometry was the presence of two clones associated with clinical or histological hyperactivity (46% versus 23% in non‐functioning cases; X2 distribution with a p < 0.05).