Zinc in microscopic calcifications isolated from thyroid fine needle aspiration may serve as a biomarker of thyroid nodule malignancy: A promising proof-of-concept

Sex-Specific Associations of Five Serum Essential Metal Elements with Thyroid Nodules in Euthyroid Adults: a Cross‑sectional Study

The association between the serum essential metal elements (magnesium, iron, copper, zinc, and calcium) and thyroid nodules is still inconsistent. The current study aims to investigate the relationship of metal elements with thyroid nodules and their malignant tendency. A total of 6480 Chinese euthyroid adults were included in our study. We collect basic information through questionnaires and medical checkups. We diagnose thyroid nodules by ultrasound and detect serum trace metal concentrations by using an automatic biochemical analyzer. Binary and multinomial logistic regressions were used to investigate the associations. As a result, we found that serum copper concentrations were positively associated with thyroid nodules in the second, third, and fourth quartiles, compared to the first quartile (P = 0.024, P = 0.016, P = 0.032) in women and P for trend is 0.038. There is a significant sex-specific association between copper concentrations and thyroid nodules (P for interaction = 0.009). The results of the multinomial logistic regression analyses indicate high serum calcium and magnesium concentrations emerged as consistent risk factors for thyroid nodules in both genders, whereas low zinc was a sex-specific factor. We also observed significant sex interactions in the relationships of magnesium (P for interaction = 0.043) with thyroid nodules with malignant tendency among participants with thyroid nodules. In conclusion, our study suggests that gender is an important factor when studying the association between serum metals and thyroid nodules. The imbalance of selected metal elements (calcium, copper, zinc, and magnesium) may relate to thyroid nodules and their malignant tendency, and future prospective studies are needed to further confirm the associations.

The clinical value of artificial intelligence in assisting junior radiologists in thyroid ultrasound: a multicenter prospective study from real clinical practice

BACKGROUND

This study is to propose a clinically applicable 2-echelon (2e) diagnostic criteria for the analysis of thyroid nodules such that low-risk nodules are screened off while only suspicious or indeterminate ones are further examined by histopathology, and to explore whether artificial intelligence (AI) can provide precise assistance for clinical decision-making in the real-world prospective scenario.

METHODS

In this prospective study, we enrolled 1036 patients with a total of 2296 thyroid nodules from three medical centers. The diagnostic performance of the AI system, radiologists with different levels of experience, and AI-assisted radiologists with different levels of experience in diagnosing thyroid nodules were evaluated against our proposed 2e diagnostic criteria, with the first being an arbitration committee consisting of 3 senior specialists and the second being cyto- or histopathology.

RESULTS

According to the 2e diagnostic criteria, 1543 nodules were classified by the arbitration committee, and the benign and malignant nature of 753 nodules was determined by pathological examinations. Taking pathological results as the evaluation standard, the sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve (AUC) of the AI systems were 0.826, 0.815, 0.821, and 0.821. For those cases where diagnosis by the Arbitration Committee were taken as the evaluation standard, the sensitivity, specificity, accuracy, and AUC of the AI system were 0.946, 0.966, 0.964, and 0.956. Taking the global 2e diagnostic criteria as the gold standard, the sensitivity, specificity, accuracy, and AUC of the AI system were 0.868, 0.934, 0.917, and 0.901, respectively. Under different criteria, AI was comparable to the diagnostic performance of senior radiologists and outperformed junior radiologists (all P < 0.05). Furthermore, AI assistance significantly improved the performance of junior radiologists in the diagnosis of thyroid nodules, and their diagnostic performance was comparable to that of senior radiologists when pathological results were taken as the gold standard (all p > 0.05).

CONCLUSIONS

The proposed 2e diagnostic criteria are consistent with real-world clinical evaluations and affirm the applicability of the AI system. Under the 2e criteria, the diagnostic performance of the AI system is comparable to that of senior radiologists and significantly improves the diagnostic capabilities of junior radiologists. This has the potential to reduce unnecessary invasive diagnostic procedures in real-world clinical practice.

The interplay between crystallinity and the levels of Zn and carbonate in synthetic microcalcifications directs thyroid cell malignancy

One of the key challenges in diagnosing thyroid cancer lies in the substantial percentage of indeterminate diagnoses of thyroid nodules that have undergone ultrasound-guided fine-needle aspiration (FNA) biopsy for cytological evaluation. This delays the definitive diagnosis and treatment plans. We recently demonstrated that hydroxyapatite microcalcifications (MCs) aspirated from thyroid nodules may aid nodule diagnosis based on their composition. In particular, Zn-enriched MCs have emerged as potential cancer biomarkers. However, a pertinent question remains: is the elevated Zn content within MCs a consequence of cancer, or do the Zn-enriched MCs encourage tumorigenesis? To address this, we treated the human thyroid cancer cell line MDA-T32 with synthetic MC analogs comprising hydroxyapatite crystals with varied pathologically relevant Zn fractions and assessed the cellular response. The MC analogs exhibited an irregular surface morphology similar to FNA MCs observed in cancerous thyroid nodules. These MC analogs displayed an inverse relationship between Zn fraction and crystallinity, as shown by X-ray diffractometry. The zeta potential of the non-Zn-bearing hydroxyapatite crystals was negative, which decreased once Zn was incorporated into the crystal. The MC analogs were not cytotoxic. The cellular response to exposure to these crystals was evaluated in terms of cell migration, proliferation, the tendency of the cells to form multicellular spheroids, and the expression of cancer markers. Our findings suggest that, if thyroid MCs play a role in promoting cancerous behavior in vivo, it is likely a result of the interplay of crystallinity with Zn and carbonate fractions in MCs.

Inhibiting Pathological Calcium Phosphate Mineralization: Implications for Disease Progression

Pathological calcifications, especially calcium phosphate microcalcifications (MCs), appear in most early breast cancer lesions, and their formation correlates with more aggressive tumors and a poorer prognosis. Hydroxyapatite (HA) is a key MC component that crystallizes in the tumor microenvironment. It is often associated with malignant breast cancer lesions and can trigger tumorigenesis in vitro. Here, we investigate the impact of additives on HA crystallization and inhibition, and how precancerous breast cells respond to minerals that are deposited in the presence of these additives. We show that nonstoichiometric HA spontaneously crystallizes in a solution simulating the tumor microenvironmental fluids and exhibits lump-like morphology similar to breast cancer MCs. In this system, the effectiveness of poly(aspartic acid) and poly(acrylic acid) (PAA) to inhibit HA is examined as a potential route to improve cancer prognosis. In the presence of additives, the formation of HA lumps is associated with the promotion or only minimal inhibition of mineralization, whereas the formation of amorphous calcium phosphate (ACP) lumps is followed by inhibition of mineralization. PAA emerges as a robust HA inhibitor by forming spherical ACP particles. When precancerous breast cells are exposed to various HA and ACP minerals, the most influential factors on cell proliferation are the mineral phase and whether the mineral is in the form of discrete particles or particle aggregates. The tumorigenic effects on cells, ranging from cytotoxicity and suppression of proliferation to triggering of proliferation, can be summarized as HA particles < HA aggregates < ACP particles < ACP aggregates. The cellular response to minerals can be attributed to a combination of factors, including mineral phase, crystallinity, morphology, surface texture, aggregation state, and surface potential. These findings have implications for understanding mineral-cell interactions within the tumor microenvironment and suggest that, in some cases, the byproducts of HA inhibition can contribute to disease progression more than HA itself.

Considerations on chemical composition of psammoma bodies: Automated detection strategy by infrared microspectroscopy in ovarian and thyroid cancer tissues

Ectopic calcifications are observed in many soft tissues and are associated with several diseases, including cancer. The mechanism of their formation and the correlation with disease progression are often unclear. Detailed knowledge of the chemical composition of these inorganic formations can be very helpful in better understanding their relationship with unhealthy tissue. In addition, information on microcalcifications can be very useful for early diagnosis and provide insight into prognosis. In this work the chemical composition of psammoma bodies (PBs) found in tissues of human ovarian serous tumors was examined. The analysis using Micro Fourier Transform Infrared Spectroscopy (micro-FTIR) revealed that these microcalcifications contain amorphous calcium carbonate phosphate. Moreover, some PB grains showed the presence of phospholipids. This interesting result corroborates the proposed formation mechanism reported in many studies according to which ovarian cancer cells switch to a calcifying phenotype by inducing the deposition of calcifications. In addition, other techniques as X-ray Fluorescence Spectroscopy (XRF), Inductively Coupled Plasma Optical Emission Spectroscopy(ICP-OES) and Scanning electron microscopy (SEM) with Energy Dispersive X-ray Spectroscopy (EDX) were performed on the PBs from ovary tissues to determine the elements present. The PBs found in ovarian serous cancer showed a composition comparable to PBs isolated from papillary thyroid. Based on the chemical similarity of IR spectra, using micro-FTIR spectroscopy combined with multivariate analysis, an automatic recognition method was constructed. With this prediction model it was possible to identify PBs microcalcifications in tissues of both ovarian cancers, regardless of tumor grade, and thyroid cancer with high sensitivity. Such approach could become a valuable tool for routine macrocalcification detection because it eliminates sample staining, and the subjectivity of conventional histopathological analysis.