Ultra-sound and cytological characteristics of the thyroid nodules in Graves’ disease

Abstract

The aim is to investigate the ultrasound and cytological characteristics of the thyroid nodules in Graves’ disease. Material and methods. Clinical, laboratory, ultrasound, cytological, immunocytochemical, cytochemical studies were performed in 59 patients with thyroid nodules in Graves’ disease. Clinical parameters
such as age of patients at the time of Graves’ disease debut, disease duration, and laboratory parameters were evaluated: thyroid-stimulating pituitary hormone levels and antibodies to the TSH receptor; ultrasonic characteristics — volume of thyroid gland, number of foci, echogenicity, echostructure, cystic changes and hyperechogenic inclusions. Cytological and immunocytochemical studies were performed on the FNA smears of foci, stained according
to Romanovsky. Indirect immunoperoxidase method with monoclonal antibodies to thyroid peroxidase, thyroglobulin and cytokeratin‑17 was used. Cytochemical studies were performed on non-fixed smears. Statistical analysis was performed by t — criterion of Student. Calculations are made in the program Statistica 10.0. Results. According to clinical study, patients with focal lesions were likely to have older age at the debut of Graves’ disease than patients with diffusely altered gland without lesions (p<0,05). Existence of focal formations were not related with such indicators as the duration of the disease, level of TSH and TSH receptor antibodies. Most patients had multisite goiter (88.1%). According to ultrasound examination all thyroid nodules had clear boundaries with a flat contour (100%), isoechogenic structure (87.5%) and cystic changes (67.8%). Cytological examination demonstrated that nodular goiter
(BSRTC‑2) was detected in 15 cases (25.42%), adenomatous nodular goiter (BSRTC‑2) — in 32 cases (54,24%), nodular goiter with B-cells (BSRTC‑2) — in 4 cases (6.78%); 6 cases (10.17%) were uninformative(BSRTC –1), in 1 case (1.69%) papillary carcinoma was detected, and in 1 — (1.69%) there was a suspicion of malignancy. Immunocytochemical and cytochemical examinations demonstrated high activity of thyroid peroxidase and thyroglobulin in FNA smears of
nodular and adenomatous goiter. At the same time, thyroid peroxidase was detected only for 18-22% of epithelial cells, Tg — in 69- 70% of thyrocytes, cytokeratyn‑17 for 4.7% of cells in FNA smears of papillary carcinoma which allowed to reveal cytological diagnosis. Conclusions. Focal lesions of the thyroid gland for Graves‘ disease are more commonly found in patients of older age at the time of the debut of Graves’ disease. For Graves disease the number of patients with multinodular goiter exceeds the number of patients with single focal entities (88.1% vs. 11.9%) and predominated features are clear boundaries, smooth contours and cystic changes. Cytological studies have shown a higher incidence of adenomatous nodular goiter (BSRTC –2) — 54.24% for Graves’ disease. Papillary carcinoma, according to the results of cytological examinations of FNA smears, was found in 1 case (1.69%), suspected malignancy also in 1 case (1.69%). Detection of cytological diagnosis of papillary carcinoma in the absence of clear cytological signs of malignancy, contributes to detection of high levels of cytokeratin‑17-positive cells and low content in the thyrocytes of thyroid peroxidase and thyroglobulin.