L-THYROXINE EFFECTS ON THYREOCYTES AND HURTHLE CELLS IN NODULAR HYPERPLASTIC GOITER ON FINE-NEEDLE ASPIRATION SAMPLES - MORPHOMETRIC EVALUATION

A morphometric study was performed on the thyreocytes and Hurthle cell s in 20 cases of nodular hyperplastic goiter (NHG) and in 8 cases of H urthle cell-rich NHG. The study was carried out on cytologic samples o btained by fine needle aspiration twice from the same nodules in a sel ected series of patients before and after L-thyroxine therapy with the aim of evaluating the morphometric nuclear variations induced by that therapy. Thyreocytes and Hurthle cells were evaluated for nuclear Are a, Perimeter, Maximum Diameter, Form Elliptic and Form Perimeter using a planimetric instrument. A statistical ly significant reduction in n uclear size tons observed in 18 of 20 cases of NHG after L-thyroxine t herapy, but the nuclear shape factors were modified only slightly or n ot at all. A slight reduction in the nuclear size of Hurthle cells was observed in five and an increase in the remaining three cases, but th ese differences were not statistically significant. Virtually no chang es in shape factors were observed in this group of lesions before or a fter the therapy. These data are discussed and compared to the results of other series. Our results suggest that morphometry may be useful i n the follow-up of NHG to evaluate the effects of L-thyroxine and that this therapy reduces the size of thyreocytes; the therapy, however, s eems to have little or no effect on Hurthle cells.