New Opportunities for Preoperative Diagnosis of Medullary Thyroid Carcinoma.

The preoperative diagnostics of medullary thyroid carcinoma (MTC), including the measuring of the blood calcitonin level, has a number of limitations. Particular focus has recently been placed on the role of miRNAs in the development of various malignant tumors; a comparative analysis of accuracy of the existing methods for MTC diagnosis with a novel diagnosis method, evaluation of the miRNA-375 expression level, was performed in this study. The expression level of miRNA-375 in cytology samples from 555 patients with the known histological diagnosis, including 41 patients with confirmed postoperative diagnosis of MTC, was assessed. The diagnostic parameters of the basal calcitonin level, calcitonin in wash-out fluid from the FNAB needle, and miRNA-375 were compared. An assessment of the miRNA-375 expression level made it possible to detect all the MTC samples with a 100% accuracy among all the 555 cytology specimens, as well as in non-informative FNAB specimens, and specimens from the ipsilateral thyroid lobe. Parameters such as sensitivity, specificity, PPV, and NPV were 100%. The miRNA-375 level, unlike calcitonin, does not correlate with tumor volume, so it does not have the so-called "gray zone". An assessment of the miRNA-375 expression allows one to accurately distinguish MTC from other malignant and benign thyroid tumors.

Persistence of primary hyperparathyroidism: a single-center experience.

BACKGROUND: Parathyroidectomy is the only definitive treatment for primary hyperparathyroidism (PHPT). Precise localization of abnormal glands is a key to a successful surgery. Most patients are expected to be successfully treated with focused parathyroidectomy. However, this approach is associated with a risk of existing multiglandular disease which may lead to the postoperative persistence of PHPT. METHODS: Eight hundred ten patients who underwent an initial surgery for PHPT at SPBU Hospital in 2017-2018 were included in the study. Preoperative imaging results were evaluated. Multivariate logistic regressions were calculated to estimate predictive values of preoperative data for the risk of postoperative persistence and risk of MGD. RESULTS: Multiglandular disease was found to be a leading cause of persistent hyperparathyroidism. An anamnesis of thyroid surgery was found to be a significant risk factor for the persistence of hyperparathyroidism. The rate of persistence did not differ significantly between groups with bilateral neck exploration and focused parathyroidectomy. Age, sex, body mass index as well as negative results of preoperative US, MIBI, and 4D CT were not independently associated with a higher risk of MGD. All preoperative imaging modalities showed from low to moderate sensitivity for the detection of MGD. The frequency of cases of a missed second adenoma did not differ significantly between patients with concordant and discordant preoperative data. There were 7 cases with previously unsuspected second adenomas found solely due to bilateral neck exploration. CONCLUSIONS: None of the combination of preoperative visualization modalities was able to rule out the MGD and reliably identify patients for focused parathyroidectomy. Additional preoperative visualization failed to improve overall results. Bilateral neck exploration appeared to have a slight benefit for the patients with concordant preoperative imaging results.

Clinical phenotypes of primary hyperparathyroidism in hospitalized patients who underwent parathyroidectomy.

OBJECTIVE: The aim of our study was to investigate the distribution of the PHPT clinical manifestations and biochemical features in patients who underwent parathyroidectomy. MATERIALS AND METHODS: Medical records of 449 patients from three Medical Centers (Saint-Petersburg, Russia), hospitalized during a period from 2011 to 2018, were reviewed. History and anthropometric data, laboratory results (iPTH, total and iCa, phosphorus, ALP, 24-h urinary calcium, 25(OH)D) and imaging data (ultrasonography, scintigraphy, CT/MRI scan, DXA) were analyzed. RESULTS: Three hundred ninety-four patients were included in the final analysis. Median age was 60 years with 94.2% being women. Symptomatic disease was evident in 222 (56.4%) patients, asymptomatic in 172 (43.6%). Skeletal involvement was more common for women, while frequency of other manifestations did not differ in both genders. There was no difference between symptomatic and asymptomatic patients in age. Serum iPTH level was higher in symptomatic patients (202.9 and 181.0 pg/mL, P = 0.022). Serum 25(OH)D level was estimated in few patients and negatively correlated with PTH (r = ¯0.294, P = 0.005), iCa (r = ¯0.268, P = 0.010) and total Ca (r = ¯0.284, P = 0.014) levels. Manifestations of CVD were observed in 67.7% of cases and affected equally both symptomatic and asymptomatic patients (70.7 and 63.4%, P = 0.076). Both age and BMI were higher in patients with CVD, whether or not they were symptomatic (62 and 53 years, P < 0.0001; 30.4 vs 26.0 kg/m2, P < 0.0001, respectively). CONCLUSIONS: This experience illustrates that symptomatic phenotype is still the most common form of PHPT.

Preoperative Typing of Thyroid and Parathyroid Tumors with a Combined Molecular Classifier.

In previous studies, we described a method for detecting and typing malignant tumors of the thyroid gland in fine-needle aspiration biopsy samples via analysis of a molecular marker panel (normalized HMGA2 mRNA level; normalized microRNA-146b, -221, and -375 levels; mitochondrial-to-nuclear DNA ratio; and BRAFV600E mutation) in cytological preparations by quantitative PCR. In the present study, we aimed to estimate the specificity of the typing of different thyroid tumors by the proposed method. Fine-needle aspiration cytological preparations from 278 patients were used. The histological diagnosis was known for each sample. The positive and negative predictive values of the method assessed in this study were, respectively, 100% and 98% for papillary thyroid carcinoma (n = 63), 100% and 100% for medullary thyroid carcinoma (n = 19), 43.5% and 98% for follicular carcinoma (n = 15), and 86% and 100% for Hürthle cell carcinoma (n = 6). Thus, we demonstrate that the diagnostic panel, including the analysis of microRNA expression, mRNA expression, the BRAFV600E mutation, and the mitochondrial-to-nuclear DNA ratio, allows the highly accurate identification of papillary thyroid carcinoma, medullary thyroid carcinoma, and Hürthle cell carcinoma but not malignant follicular tumors (positive predictive value was below 50%).