Calcitonin levels by ECLIA correlate well with RIA values in higher range but are affected by sex, TgAb, and renal function in lower range

Gender and tumor size-specific calcitonin cutoff value for diagnosing MTC in 10,618 patients with thyroid nodule surgery

BACKGROUND

Calcitonin is a sensitive marker for medullary thyroid carcinoma (MTC) diagnosis and postsurgical follow-up. This study aimed to define the gender and tumor size-specific calcitonin cutoff values for diagnosing MTC.

METHODS

This retrospective study recruited 95 MTC patients and 10,523 non-MTC patients who underwent thyroid nodule surgery at Zhongshan Hospital between January 2015 and June 2023. Receiver operating characteristic (ROC) curves were used to assess calcitonin cutoff values for diagnosing MTC.

RESULTS

Calcitonin levels in non-MTC patients were influenced by gender, CKD stage and age, with gender being the highest ranked predictor. In MTC patients, calcitonin levels were associated with tumor diameter, lymph node metastasis, and TNM stage. In the entire study population, calcitonin cutoff values to diagnose MTC were 17.75 pg/mL for males (sensitivity: 97.60%, specificity: 99.40%) and 7.15 pg/mL for females (sensitivity: 94.34%, specificity: 99.22%). In patients with a thyroid nodule diameter ≤10 mm, the calcitonin cutoff values to diagnose MTC were 17.50 pg/mL for males (sensitivity: 95.00%, specificity: 99.27%) and 7.15 pg/mL for females (sensitivity: 90.91%, specificity: 99.04%). In patients with a thyroid nodule diameter >10 mm, the calcitonin cutoff values to diagnose MTC were 104.80 pg/mL for males (sensitivity: 100.00%, specificity: 100.00%) and 32.60 pg/mL for females (sensitivity: 96.77%, specificity: 100.00%).

CONCLUSION

We have identified the gender and tumor size-specific cutoff values for the diagnosis of MTC. Cutoff values based on gender and tumor diameter may help to improve the accuracy of preoperative diagnosis of MTC, which is worth to be verified by future studies.

Impact of dietary, lifestyle and sociodemographic factors on calcitonin levels in a healthy population

Calcitonin (CT), a hormone secreted by thyroid parafollicular C cells, plays a role in calcium homeostasis and bone health. Understanding the relationship between CT levels and dietary, sociodemographic, and lifestyle factors is essential for public health and hormonal balance studies. This study encompassed 3323 healthy participants from the Croatian biobank. We utilized principal component analysis (PCA) to reduce food items into dietary patterns. Regression analysis was used to investigate the relationship between CT levels and data collected through questionnaires, accounting for age and sex. CT levels exhibited sex-specific differences, with higher values observed in males. Positive associations were found between CT levels and age, body mass index (BMI), as well as weekly consumption of white and red wine mixed with water. While height and sternal notch-finger length initially correlated positively with CT levels, this relationship reversed upon adjusting for age and sex. Regarding sport activities, CT levels were significantly increased in non-participants compared to occasional sport participants (p = 0.043). Dietary factors yielded intriguing findings, with frequent consumption of butter, animal fat and veal associated with lower CT levels, while higher CT levels were associated with the frequent consumption of white fish, blue fish, pasta, and rice. However, no significant correlation was found between CT levels and bone mineral density (BMD), weight, or body surface area (BSA). This study highlights the complex interplay of dietary, lifestyle, and sociodemographic factors influencing CT levels. These findings suggest that a broad range of factors should be considered in hormonal balance studies, underlining their potential implications for public health.

Application of Enzyme-Linked Fluorescence Assay (ELFA) to Obtain In Vivo Matured Dog Oocytes through the Assessment of Progesterone Level

Successful dog cloning requires a sufficient number of in vivo matured oocytes as recipient oocytes for reconstructing embryos. The accurate prediction of the ovulation day in estrus bitches is critical for collecting mature oocytes. Traditionally, a specific serum progesterone (P4) range in the radioimmunoassay (RIA) system has been used for the prediction of ovulation. In this study, we investigated the use of an enzyme-linked fluorescence assay (ELFA) system for the measurement of P4. Serum samples of estrus bitches were analyzed using both RIA and ELFA, and the measured P4 values of ELFA were sorted into 11 groups based on the standard concentration measured in RIA and compared. In addition, to examine the tendency of changes in the P4 values in each system, the P4 values on ovulation day (from D - 6 to D + 1) in both systems were compared. The ELFA range of 5.0-12.0 ng/mL was derived from the RIA standard range of 4.0-8.0 ng/mL. The rates of acquired matured oocytes in RIA and ELFA were 55.47% and 65.19%, respectively. The ELFA system successfully produced cloned puppies after the transfer of the reconstructed cloned oocytes. Our findings suggest that the ELFA system is suitable for obtaining in vivo matured oocytes for dog cloning.

Calcitonin Levels in Thyroid Disease Are Not Affected by Autoimmune Thyroiditis or Differentiated Thyroid Carcinoma

INTRODUCTION

Association between hypercalcitoninemia and pathological conditions such as autoimmune thyroiditis (AIT) or differentiated thyroid carcinoma (DTC) has been addressed, with conflicting results. We evaluated the prevalence and the clinical relevance of elevated basal serum calcitonin (CT) levels in non-neoplastic (nodular goiter [NG] and AIT) and neoplastic thyroid diseases (DTC).

METHODS

We retrospectively evaluated 3,250 consecutive patients with thyroid nodular disease who underwent fine-needle aspiration cytology with adequate sample. After exclusion of medullary thyroid cancer (MTC) patients were divided according to the presence/absence of thyroid autoimmunity into NG or nodular autoimmune thyroiditis (N-AIT) and, according to cytological results, in benign or suspicious/malignant nodules.

RESULTS

One hundred ninety-seven/3,250 patients (6.0%) showed CT level >10 pg/mL. In 11/3,250 (0.3%) cases, a final histological diagnosis of MTC was made, while the remaining 186/3,250 patients (5.7%) had non-MTC-related hypercalcitoninemia (CT > 10 pg/mL). According to cytological diagnosis, the rate of hypercalcitoninemia was similar in class II and class V-VI groups (5.4 vs. 6.9%, p = 0.4). The occurrence of hypercalcitoninemia was significantly higher in patients with NG (166/2,634 [6.3%]) than in patients with N-AIT (20/605 [3.3%]) (p = 0.004). However, after matching by sex, no difference was found between the 2 groups (NG and N-AIT). These results were confirmed in 598 patients submitted to surgery.

CONCLUSIONS

AIT and DTC seem not to affect serum CT levels in patients with thyroid nodules. Therefore, hypercalcitoninemia, in these patients, should be submitted to the same diagnostic workup than patients without AIT or DTC.