The influence of the vascularisation of the follicular thyroid nodules on the proliferative activity of the follicular cells

Abstract

The enlargement of the thyroid is, in general, benign in origin and due to nodular goitre. Follicular cellular proliferation of thyroid nodules has been increasingly observed recently. With fine needle aspiration biopsy (FNAB) this is classified as a follicular tumour. These lesions present various patterns of vascularisation in ultrasound examination. The aim of the study was to establish the relation between follicular nodule vascularisation and the proliferative activity of various types of follicular cell. According to the manner of proliferation, patients were divided into groups as follows: (I) patients with hyperplastic nodules (46 cases), (II) patients with follicular adenoma (42 cases), and (III) patients with follicular cancer (9 cases). In each case B-mode sonography, Power Doppler, sonographically guided FNAB (S-FNAB), morphological examination and morphometry were performed. The proliferative activity was detected with immunohistochemical methods (PCNA, Ki 67 and MPM2) to determine the so-called “proliferative index”. The study revealed increased proliferative activity in tumours of malignant origin and increased vascularisation in coexistence with increased proliferation of the follicular cells. As assessed by Power Doppler, an increased flow pattern in the centre of the nodules correlates with increased proliferative activity. The results suggest that Power Doppler examination could be helpful in selecting nodules for FNAB, especially in multinodular goitre.