The potentialities of echography in the differential diagnosis of thyroid follicular tumors

This study aimed to explore the potentialities of echography in the differential diagnosis of thyroid follicular tumors. For comparative analysis of echographic images of thyroid follicular tumors our study included two groups of patients who had undergone surgery for thyroid follicular tumor. Group 1 consisted of 55 patients with follicular adenoma, and group 2 consisted of 16 patients with thyroid cancer. In total, 71 patients were examined. All of the patients underwent preoperative fine-needle aspiration biopsy of thyroid nodules under ultrasound guidance. In all cases, cytological diagnosis of follicular tumor was reported. Morphological findings were confirmed after surgery. The size of detected tumors ranged from 4´2 mm to 60´28 mm (group 1) and from 5´4 mm to 75´34 mm (group 2). Tumors of more than 2 cm in diameter were detected in 29 (52.73%) patients (group 1) and in 13 (81.25%) patients (group 2). Tumor borders were well defined in 54 (98.1%) patients in group 1 and in all the patients in group 2. Grey-scale ultrasound revealed a prevalence of isoechoic tumors in both groups: in 38 (69%) cases (group 1) and in 12 (75%) cases (group 2). A hypoechoic halo was seen in 51 (93%) patients in group 1 and in all the patients in group 2. In group 1, calcifications were found in 2 (3.64%) cases, and in group 2, no calcifications were present. The majority of tumors had a solid structure. The cystic component was absent in 39 (70.9%) cases (group 1) and in 10 (62.5%) cases (group 2). Vascularity of the tumor was evaluated using power Doppler ultrasound. Tumors appeared hypervascular in 39 (70.9%) cases (group 1) and in 11 (68.75%) cases (group 2). Mixed tumor blood flow predominated in both groups: in 50 (90.9%) cases (group 1) and in 14 (87.5%) cases (group 2). In most cases, follicular adenomas and thyroid cancers appeared as isoechoic tumors with well-defined borders and a hypoechoic halo that did not have calcifications or cystic components. They were typically hypervascular and showed mixed blood flow on colour and power Doppler examination. The results of our study indicated that there were no pathognomonic sonographic features of follicular adenoma or thyroid cancer among follicular tumors.