THYROID NODULAR HYPERPLASIA - CHROMOSOMAL STUDIES IN 14 CASES

Cytogenetic study of 14 thyroid nodular hyperplasias revealed a hyperd iploid karyotype in two cases (14%) and a normal chromosomal complemen t in the remaining cases. Some of the numerical alterations found were identical to the ones considered characteristic of a subset of thyroi d adenomas (+5, +7, +9, +12, +14, and +16). Our findings suggest that the cytogenetic events involved in the pathogenesis of thyroid hyperpl astic lesions and benign tumors may be closely related, which supports the hypothesis of a biologic ''continuum'' between these two types of lesions.