The feasibility of using immunocytochemical research in the preoperative diagnosis of thyroid tumors

Background. Thyroid cancer has long been an urgent problem of health care in Ukraine and requires both improved timely detection of the disease and increased coverage by special treatment of this category of patients to improve its results. Objective. Investigate the complex of immunocytochemical and ultrasound characteristics of thyroid tumors to improve diagnostic algorithms in the preanalytical stage. Methods. During the the research work the results of diagnostics of 60 patients with thyroid neoplasms aged 21 to 83 years who underwent fine-needle aspiration. Patients were divided into three groups according to the Bethesda System (BSRTC) classification category. The 1st group included 18 patients of category II BSRTC (Benign. Group 2 included 20 patients with category V BSRTC (Suspicious for Malignancy – SFM). And other 22 patients with category VI BSRTC (malignant tumor) formed the 3rd group). Patients of all groups underwent questionnaires, ultrasound examination with FNA, cytological and immunocytochemical examination. Results. There is no clear link between E-cadherin expression and neoplasia. Negative expression occurred in 36.4% of cases of metastatic lesions. This partially satisfies the requirements of timely preoperative diagnosis. That is why E-cadherin cannot be used as a separate marker. The expression of cytokeratin-19 with different degrees of intensity of cytoplasmic staining of tumor cells was determined in all studied neoplasms of V and VI category on the BSRTC scale. Strong expression of cytokeratin-19 was observed in 40.0% of cases with BSRTC-5 and 45.4% with BSRTC-6, moderate - in 50.0% and 36.4% of cases, respectively, weak - in 10.0% and 18.2%, without significant differences between groups (p> 0.05). At the same time, in the benign process in 55.6% of cases there was no reaction of cytokeratin-19, and in 44.4% - weak expression (p <0.001 in comparison with the 2nd and 3rd groups). Conclusion. Benign thyroid disease (category II BSRTC) is likely to be associated with younger patients (46.6 ± 3.7 years), low serum REA (less than 0.95 ng / ml), poor thyroglobulin expression (77.8 %), negative reaction with TTF-1 (100%) and cytokeratin-19 (55.6%). Differential-prognostic markers of thyroid cancer with risk of malignancy (V category BSRTC) include elevated serum REA (0.95 ng / ml and above), the presence of a moderate reaction with antibodies to thyroglobulin (80.0%), a positive reaction - to TTF-1 (100.0%) and E-cadherin (90.0%), with moderate or strong expression of cytokeratin-19 (90.0%).