Endemic Goiter and Iodine Prophylaxis in Calabria, a Region of Southern Italy: Past and Present

Incidental thyroid carcinoma in an endemic goiter area in Italy: histopathological features and predictors of a common finding

PURPOSE

The occurrence and histopathological features of incidental thyroid carcinoma (ITC) vary considerably among populations from different geographical regions. The aim of this study is to assess the prevalence and histopathological characteristics of ITC in patients who underwent thyroid surgery for apparently benign thyroid diseases in an endemic goiter area in Italy.

METHODS

A total of 649 consecutive patients (531 females and 118 males; mean age, 52.9 ± 11.0 years), who underwent thyroid surgery at the Endocrine Surgery Unit of the tertiary care "Renato Dulbecco" University Hospital (Catanzaro, Italy) in the period between years 2017 and 2022, were included in this retrospective study. A comprehensive histopathological examination was performed on surgically excised thyroid tissue. Logistic regression analysis was employed to identify potential predictors of ITC.

RESULTS

The histopathological examination revealed the presence of ITC in 81 patients, accounting for 12.5% of the total study population. The female to male ratio was found to be 6.4 to 1. Among the patients with ITC, 72 had papillary carcinoma (PTC), with 53 of these tumors being microcarcinomas (microPTC). Additionally, 5 patients had follicular thyroid carcinoma, 2 patients had low-risk follicular cell-derived thyroid neoplasms, 1 patient had an oncocytic carcinoma, and 1 patient had a medullary thyroid carcinoma. Logistic regression analysis demonstrated a significant association between female sex and incidental microPTC.

CONCLUSIONS

These findings provide further evidence of the common occurrence of ITC, typically in the form of microPTC, among individuals who undergo thyroid surgery for apparently benign thyroid diseases.

Coexistence of Hashimoto's Thyroiditis in Differentiated Thyroid Cancer: Post-Operative Monitoring of Anti-Thyroglobulin Antibodies and Assessment of Treatment Response

INTRODUCTION

Differentiated thyroid carcinoma (DTC) is frequently found in conjunction with autoimmune thyroid disorders, particularly Hashimoto's thyroiditis (HT). This study investigates the impact of coexisting HT on the persistence of an indeterminate response to therapy due to positive anti-thyroglobulin antibodies (AbTg), measured via competitive immunoassay, in a consecutive patient series from Calabria, Southern Italy.

METHODS

This retrospective longitudinal study analyzed 259 consecutive DTC patients managed at the Endocrinology Unit of Renato Dulbecco Hospital (Catanzaro, Italy) up to 2023. Patients with medullary and undifferentiated thyroid carcinoma, partial thyroidectomy, less than six months of post-operative monitoring, or missing clinical data were excluded. Demographic information, histological findings, initial tumor stage, and ATA risk category were collected. The response to therapy was assessed based on ATA guidelines.

RESULTS

Among the 259 patients, 29% had coexisting HT. Patients with HT exhibited distinct characteristics: a higher proportion of females (87.0% vs. 74.7%), a shorter post-operative monitoring duration (median 3 vs. 5 years), and a higher prevalence of papillary thyroid carcinoma (PTC) (97.4% vs. 86.3%). The tumor size, lymph node involvement, and distant metastasis were similar between the groups, with patients without HT having a higher incidence of extrathyroidal tumor extension. However, the initial TNM stage and ATA risk category did not differ significantly. At the six-month follow-up, HT patients showed a higher rate of indeterminate responses, primarily due to positive AbTg. After 12 months, the response categories aligned, with decreasing AbTg levels in the HT group. After 24 months, most patients with long-term follow-up demonstrated an excellent response to DTC therapy, irrespective of HT coexistence.

CONCLUSIONS

While HT does not worsen DTC prognosis, it may result in indeterminate responses. AbTg measurements in the peri-operative period should be encouraged to facilitate post-operative monitoring, emphasizing the importance of using standardized assays. Further research in larger populations with extended follow-up is needed to comprehensively understand the HT-DTC relationship.

Iodine Deficiency and Iodine Prophylaxis: An Overview and Update

The thyroid gland requires iodine to synthesize thyroid hormones, and iodine deficiency results in the inadequate production of thyroxine and related thyroid, metabolic, developmental, and reproductive disorders. Iodine requirements are higher in infants, children, and during pregnancy and lactation than in adult men and non-pregnant women. Iodine is available in a wide range of foods and water and is susceptible to almost complete gastric and duodenal absorption as an iodide ion. A healthy diet usually provides a daily iodine consumption not exceeding 50% of the recommended intake. Iodine supplementation is usually necessary to prevent iodine deficiency disorders (IDDs), especially in endemic areas. The community-based strategy of iodine fortification in salt has eradicated IDDs, such as endemic goiter and cretinism, in countries providing adequate measures of iodine prophylaxis over several decades in the 20th century. Iodized salt is the cornerstone of iodine prophylaxis in endemic areas, and the continuous monitoring of community iodine intake and its related clinical outcomes is essential. Despite the relevant improvement in clinical outcomes, subclinical iodine deficiency persists even in Western Europe, especially among girls and women, being an issue in certain physiological conditions, such as pregnancy and lactation, and in people consuming unbalanced vegetable-based or salt-restricted diets. Detailed strategies to implement iodine intake (supplementation) could be considered for specific population groups when iodized salt alone is insufficient to provide adequate requirements.

Sonoelastographic Evaluation of Recurrent Thyroid Nodules in Patients with Operated Recurrent Nodular Goiters

Alterations in neck anatomy after thyroid surgery and post-operative fibrosis may be misleading by causing sonoelastographic changes in recurrent tissues in patients with recurrent nodular goiter and so may result in unnecessary biopsies or surgical procedures. Here, the aim was to examine thyroid sonoelastography values in patients developing a recurrence and presenting with recurrent nodular goiter with benign cytology after total or near-total thyroidectomy (T/N-TT). Twenty-nine nodules from 22 patients with a recurrence after T/N-TT whose biopsies were found to be benign constituted the patients, and 23 nodules from 23 participants among the non-operated patients having solitary or multiple thyroid nodules and with age, gender and body mass index values similar to those of the patients constituted our controls. Shear-wave velocity (SWV) values were measured. Average elapsed time after T/N-TT was 11.82 (4:25) y. No difference was detected between the groups in terms of localization and sonographic structures of the nodules. Nodule SWV values were higher in the operated recurrent nodular goiter group than in the controls (2.93 ± 0.87 m/s vs. 2.43 ± 0.33 m/s, respectively, p = 0.011). Because SWV values are high in operated recurrent nodular goiter patients, the utilization of reference sonoelastography values in those with unoperated goiter may yield misleading results in the differentiation of benign and malignant lesions.

Iodine Intake Estimated by 24 h Urine Collection in the Italian Adult Population: 2008-2012 Survey

Monitoring the population iodine status is essential for iodine deficiency eradication. This study assessed the average dietary iodine intake and the iodine status of a random sample of the Italian general adult population. The study population included 2378 adults aged 35-79 years (1229 men and 1149 women) from all 20 Italian regions, participating in the Osservatorio Epidemiologico Cardiovascolare/Health Examination Survey 2008-2012 (OEC/HES), and were examined for iodine intake in the framework of the MINISAL-GIRCSI Programme. Dietary iodine intake was assessed by the measurement of 24 h urinary iodine excretion. The median daily iodine intake of the whole population was lower (96 µg/d, interquartile range 51-165) than the daily adequate iodine intake according to both EFSA and WHO recommendation (150 µg/d), with a significantly lower value among women (85 µg/d) compared with men (111 µg/d). Iodine intake diminished with age and increased with BMI (body mass index) in male but not in female participants, without achieving the adequate intake in any sex, age, or BMI category. In this random sample of Italian general adult population examined in 2008-2012, iodine intake still remained lower than the recommended values despite the implementation of a strategy of iodoprophylaxis based on salt iodization in 2005. These data represent a valuable reference for future monitoring of iodine status in our country.

Malignancy Analyses of Thyroid Nodules in Patients Subjected to Surgery with Cytological- and Ultrasound-Based Risk Stratification Systems

The fine needle aspiration (FNA) cytology is the gold standard for the preoperative diagnosis of thyroid cancer. However, up to 30% of FNA examinations yield nondiagnostic or indeterminate results and this complicates patient management. Clinical features and ultrasound (US) patterns, including US risk stratification systems, could be useful in the preoperative diagnostic workup and prediction of malignancy, but the evidences are not univocal. Methods: 400 consecutive patients subjected to thyroid surgery were retrospectively enrolled at our institution in Calabria, Southern Italy. Preoperative US and FNA cytological descriptions, formulated according to the “Italian consensus for reporting thyroid fine-needle aspiration cytology” (ICCRTC) classification and three US risk stratification systems (those developed by the American Association of Clinical Endocrinologists, American College of Endocrinology and Associazione Medici Endocrinologi (AACE/ACE/AME), American Thyroid Association (ATA), and American College of Radiology (ACR-TIRADS)), were collected, along with histological results. Results: 147 thyroid cancer cases, in large majority papillary carcinomas, were detected on final histological examination. Almost two-thirds of patients subjected to thyroid surgery for either benign or malignant lesions were female. Patient’s age ≤20 years and between 21–30 years were clinical features associated with increased risk of thyroid cancer in logistic regression analyses. US features associated with thyroid cancer included irregular margins, solid composition, microcalcifications, and marked hypoechogenicity. The AACE/ACE/AME, ATA, and ACR-TIRADS risk categories, corresponding to specific US patterns, were strong predictors of malignancy in both genders, but not in nodules with indeterminate cytology. A measured difference between the longitudinal (L) and the anteroposterior (AP) diameter >5 mm, a proxy for a parallel-oriented oval shape of a nodule, emerged as a robust protective factor against thyroid cancer (OR 0.288 (95%CI 0.817–0.443); p < 0.001), regardless of cytological risk. Conclusions: Some, but not all, well-established predictors of TC have been confirmed in this study. Controversy surrounds the diagnostic performance of US risk stratification systems for the detection of thyroid cancer in the subgroup of nodules with indeterminate cytology, suggesting their use only to set the thresholds for FNA. A measured difference between L and AP diameters >5 mm may represent an additional and practical tool for ruling out malignancy in thyroid nodules, with the potential to reduce unnecessary surgical procedures.

Interference on Iodine Uptake and Human Thyroid Function by Perchlorate-Contaminated Water and Food

BACKGROUND

Perchlorate-induced natrium-iodide symporter (NIS) interference is a well-recognized thyroid disrupting mechanism. It is unclear, however, whether a chronic low-dose exposure to perchlorate delivered by food and drinks may cause thyroid dysfunction in the long term. Thus, the aim of this review was to overview and summarize literature results in order to clarify this issue.

METHODS

Authors searched PubMed/MEDLINE, Scopus, Web of Science, institutional websites and Google until April 2020 for relevant information about the fundamental mechanism of the thyroid NIS interference induced by orally consumed perchlorate compounds and its clinical consequences.

RESULTS

Food and drinking water should be considered relevant sources of perchlorate. Despite some controversies, cross-sectional studies demonstrated that perchlorate exposure affects thyroid hormone synthesis in infants, adolescents and adults, particularly in the case of underlying thyroid diseases and iodine insufficiency. An exaggerated exposure to perchlorate during pregnancy leads to a worse neurocognitive and behavioral development outcome in infants, regardless of maternal thyroid hormone levels.

DISCUSSION AND CONCLUSION

The effects of a chronic low-dose perchlorate exposure on thyroid homeostasis remain still unclear, leading to concerns especially for highly sensitive patients. Specific studies are needed to clarify this issue, aiming to better define strategies of detection and prevention.

Effects of Iodine Intake and Nutraceuticals in Thyroidology: Update and Prospects

Iodine is a microelement that is naturally present in some foods, added to others, and available as a dietary supplement [...].