Since parathyroid hormone (PTH) was first isolated and its gene (PTH) was sequenced, only eight PTH mutations have been discovered. The C18R mutation in PTH, discovered in 1990, was the first to be reported. This autosomal dominant mutation induces endoplasmic reticulum stress and subsequent apoptosis in parathyroid cells. The next mutation, which was reported in 1992, is associated with exon skipping. The substitution of G with C in the first nucleotide of the second intron results in the exclusion of the second exon; since this exon includes the initiation codon, translation initiation is prevented. An S23P mutation and an S23X mutation at the same residue were reported in 1999 and 2012, respectively. Both mutations resulted in hypoparathyroidism. In 2008, a somatic R83X mutation was detected in a parathyroid adenoma tissue sample collected from a patient with hyperparathyroidism. In 2013, a heterozygous p.Met1_Asp6del mutation was incidentally discovered in a case-control study. Two years later, the R56C mutation was reported; this is the only reported hypoparathyroidism-causing mutation in the mature bioactive part of PTH. In 2017, another heterozygous mutation, M14K, was detected. The discovery of these eight mutations in the PTH gene has provided insights into its function and broadened our understanding of the molecular mechanisms underlying mutation progression. Further attempts to detect other such mutations will help elucidate the functions of PTH in a more sophisticated manner.

Background: Concerns have been raised regarding thyroid disorders caused by excessive iodine in Koreans, who have iodine-rich diets. This study evaluated iodine status using dietary iodine intake and urinary iodine in papillary thyroid cancer (PTC) patients. Methods: Dietary data of PTC patients were assessed using a 24-hour recall and food frequency questionnaire (FFQ), and urinary iodine concentrations (UICs) were also obtained. To compare the iodine status of PTC patients, Korean adults with or without thyroid disease from the Korea National Health and Nutrition Examination Survey, which had 24-hour recall data and urinary iodine measurements, were analyzed. Results: The median daily iodine intake by 24-hour recall was 341.7 μg/day in PTC patients, similar to the levels of other Korean adults. Based on UICs, the prevalence of excessive iodine was 54.4% in PTC patients, which was similar to the prevalence among subjects with thyroid disease (55.4%) but slightly higher than that in subjects without thyroid disease (47.7%). Based on dietary iodine by 24-hour recall, the prevalence of excessive iodine intake was 7.2%, which was higher than that among subjects with (4.4%) or without (3.9%) thyroid disease. The dietary iodine intake based on 24-hour recall was closely correlated with the UIC (r=0.4826) in PTC patients, but dietary iodine by FFQ was not significantly correlated with either 24-hour recall or UIC-based dietary iodine. Conclusion Excessive iodine intake was more common in PTC patients than in subjects without thyroid disease. Further longitudinal research is necessary to elucidate the role of dietary iodine in PTC.

Background: Concerns have been raised regarding thyroid disorders caused by excessive iodine in Koreans, who have iodine-rich diets. This study evaluated iodine status using dietary iodine intake and urinary iodine in papillary thyroid cancer (PTC) patients. Methods: Dietary data of PTC patients were assessed using a 24-hour recall and food frequency questionnaire (FFQ), and urinary iodine concentrations (UICs) were also obtained. To compare the iodine status of PTC patients, Korean adults with or without thyroid disease from the Korea National Health and Nutrition Examination Survey, which had 24-hour recall data and urinary iodine measurements, were analyzed. Results: The median daily iodine intake by 24-hour recall was 341.7 μg/day in PTC patients, similar to the levels of other Korean adults. Based on UICs, the prevalence of excessive iodine was 54.4% in PTC patients, which was similar to the prevalence among subjects with thyroid disease (55.4%) but slightly higher than that in subjects without thyroid disease (47.7%). Based on dietary iodine by 24-hour recall, the prevalence of excessive iodine intake was 7.2%, which was higher than that among subjects with (4.4%) or without (3.9%) thyroid disease. The dietary iodine intake based on 24-hour recall was closely correlated with the UIC (r=0.4826) in PTC patients, but dietary iodine by FFQ was not significantly correlated with either 24-hour recall or UIC-based dietary iodine. Conclusion Excessive iodine intake was more common in PTC patients than in subjects without thyroid disease. Further longitudinal research is necessary to elucidate the role of dietary iodine in PTC.

Purpose: Intraoperative neurophysiological monitoring (IONM) has been introduced in thyroid surgery to prevent injury of the recurrent laryngeal nerve (RLN). However, its effectiveness remains controversial in robotic thyroidectomy (RT). This study aimed to compare the surgical outcome of RT in patients with and without the application of IONM. Methods: This retrospective case-control study included 100 patients who underwent total thyroidectomy via robotic bilateral axillo-breast approach in a tertiary center. A study group of 50 patients who had IONM during RT was compared to a control group of 50 patients who underwent RT with nerve visualization alone. Results: The sex ratio (4:45 vs. 7:43, P = 0.538), mean age (39.3 ± 7.1 years vs. 37.5 ± 10.4 years, P = 0.304), and body mass index (23.1 ± 2.6 kg/m2 vs. 22.2 ± 3.9 kg/m2 , P = 0.215) were comparable between the IONM and control groups. Pathologic features including tumor size (0.8 cm vs. 0.9 cm, P = 0.283), extrathyroidal extension (58.0% vs. 24.0%, P = 0.316), lymph node metastasis (30% vs. 34%, P = 0.668), and number of lymph nodes (5.3 vs. 5.3, P = 0.668) showed no differences. There was no permanent RLN palsy, postoperative bleeding, and wound complications. Transient hypoparathyroidism was observed in 12 (24.0%) and 14 (28.0%), permanent hypoparathyroidism in 0 (0%) and 1 (2.0%), and transient RLN palsy was observed in 3 (6.0%) and 3 (6.0%), respectively. Conclusion We did not demonstrate a clear advantage of IONM in RT. Controversies regarding the effectiveness of IONM is not closed.

PURPOSE: Although many Koreans consume traditional alternative remedial products to alleviate symptoms of fatigue, there have been no studies on their effect on thyroid function levels in thyroidectomized patients on levothyroxine replacement. The aim of this study was to assess the effect of Korean traditional alternative remedies on thyroid function levels in post total thyroidectomy patients.METHODS: A retrospective review of medical records from a single tertiary referral center was performed on patients who received total thyroidectomy from 2010 to 2015 and became euthyroid postoperatively. Gender, age, body mass index, preoperative thyroid function test results, interval to first hypothyroidism occurrence, recurrence of hypothyroidism, number and types of alternative remedy were evaluated.RESULTS: Postoperative hypothyroidism occurred among 174 out of 917 patients (18.9%) and 100 (57.5%) of them had a history of alternative medication usage. The first episode of hypothyroidism occurred at median of 38.5 months after operation in the 100 patients. Six of the 100 patients received an increased dosage of levothyroxine due to severe hypothyroidism but the rest received the same dose and were requested not to consume alternative products. All patients recovered to euthyroid status afterwards. Thirty-three patients subsequently experienced recurrence even after being restricted from consuming alternative remedial products. Apart from thyroiditis on pathology reports (P=0.001), there were no variables significantly related to the recurrent hypothyroidism.CONCLUSION: This pilot study demonstrated the possible role of consumption patterns of traditional alternative remedial products in thyroidectomized patients under hormone supplement in restoring euthyroid status without levothyroxine increase.
Body Mass Index ; Complementary Therapies ; Fatigue ; Herb-Drug Interactions ; Humans ; Hypothyroidism ; Medical Records ; Pathology ; Pilot Projects ; Recurrence ; Retrospective Studies ; Tertiary Care Centers ; Thyroid Function Tests ; Thyroid Gland ; Thyroidectomy ; Thyroiditis ; Thyroxine

Background: Although smoking is generally carcinogenic, its effect on thyroid cancers is still subject to controversy. The purpose of this study was to summarize the role of smoking in relation to thyroid cancer occurrence. Methods: We performed a meta-analysis of 24 eligible studies: 21 case-control studies and three prospective cohort studies. The summary odds ratio (OR) and 95% confidence interval (CI) of all studies were acquired based on random effect model. Further subgroup analyses were conducted according to gender, histological type of thyroid cancer, and smoking status of patients for the case-control studies. Results: The summary effect size indicated a negative association of smoking for thyroid cancer (OR, 0.798; 95% CI, 0.681 to 0.935). From the subgroup analyses for the case-control studies, reduced risk of thyroid cancer was observed in both men (OR, 0.734; 95% CI, 0.553 to 0.974) and women (OR, 0.792; 95% CI, 0.700 to 0.897). The protective effect of smoking was observed in studies in which thyroid cancer was limited to differentiated thyroid cancers (DTCs) (OR, 0.798; 95% CI, 0.706 to 0.902). Conclusion Our results suggests that smoking may have a protective effect on thyroid cancer, especially on DTCs. Further studies with larger sample sizes should be conducted in elucidating the dose and time dependent effect of smoking on thyroid cancer with specific focus on the types of thyroid cancers.

Background: Although smoking is generally carcinogenic, its effect on thyroid cancers is still subject to controversy. The purpose of this study was to summarize the role of smoking in relation to thyroid cancer occurrence. Methods: We performed a meta-analysis of 24 eligible studies: 21 case-control studies and three prospective cohort studies. The summary odds ratio (OR) and 95% confidence interval (CI) of all studies were acquired based on random effect model. Further subgroup analyses were conducted according to gender, histological type of thyroid cancer, and smoking status of patients for the case-control studies. Results: The summary effect size indicated a negative association of smoking for thyroid cancer (OR, 0.798; 95% CI, 0.681 to 0.935). From the subgroup analyses for the case-control studies, reduced risk of thyroid cancer was observed in both men (OR, 0.734; 95% CI, 0.553 to 0.974) and women (OR, 0.792; 95% CI, 0.700 to 0.897). The protective effect of smoking was observed in studies in which thyroid cancer was limited to differentiated thyroid cancers (DTCs) (OR, 0.798; 95% CI, 0.706 to 0.902). Conclusion Our results suggests that smoking may have a protective effect on thyroid cancer, especially on DTCs. Further studies with larger sample sizes should be conducted in elucidating the dose and time dependent effect of smoking on thyroid cancer with specific focus on the types of thyroid cancers.

Background: The cytologic diagnosis of poorly differentiated thyroid carcinoma (PDTC) is difficult because it lacks salient cytologic findings and shares cytologic features with more commonly encountered neoplasms. Due to diverse cytologic findings and paucicellularity of PDTC, standardization of cytologic diagnostic criteria is limited. The purpose of this study is to investigate and recognize diverse thyroid findings of fine needle aspiration (FNA) cytology and frozen smear cytology in diagnosis of this rare but aggressive carcinoma. Methods: The present study included six cases of FNA cytology and frozen smears of histologically diagnosed PDTCs. Results: PDTC showed cytologic overlap with well-differentiated thyroid carcinomas (WDTCs). Five of six cases showed dedifferentiation arising from well differentiated thyroid carcinomas. Only one de novo PDTC showed highly cellular smears composed of discohesive small cells, high nuclear/cytoplasmic (N/C) ratio, prominent micronucleoli, and irregular nuclei. Retrospectively reviewed, these findings are highly suspicious for PDTC. Cytologic findings of nuclear atypia, pleomorphism, and irregularity were frequently found, whereas scattered small cells were seen only in the de novo case. Conclusions Heterogeneous cytologic findings of PDTCs are shared with those of WDTCs and contribute to difficult preoperative cytologic diagnoses. Most PDTCs show dedifferentiation from WDTCs. Albeit rare, de novo PDTC should be considered with cytology showing discohesive small cells with high N/C ratio. This will enable precise diagnosis and prompt treatment of this aggressive malignancy

BACKGROUND: The sodium/iodide symporter (NIS) has an important role in the diagnosis and treatment of well differentiated thyroid carcinoma. The relationship between the uptake of thallium- 201 scan (201Tl scan) and the expression of sodium/iodide symporter (hNIS) was studied in thyroid nodules. METHODS: Patients that had undergone operations for thyroid nodules, and who received a 201Tl scan before their operations, were investigated. Anti-NIS antibodies were used to analyze the presence and distribution of the hNIS protein by immunohistochemical staining of their thyroid tissues. RESULTS: Forty-four patients (papillary carcinoma; 18, follicular adenoma; 11, adenomatous goiter; 14, nonspecific thyroiditis; 1) 30 with no immunoreactivity and 14 with a positive reaction to the anti-NIS antibody, were included. The NIS negative patients (12/30) had no 201Tl uptake, but all others were positive on 201Tl scan, and the NIS-positive patients (13/14) had positive 201Tl uptake, with 1 negative on 201Tl scan, with significant difference (p=0.035). Of the 18 patients with a papillary thyroid carcinoma, the NIS negative patients (2/10) had no 201Tl uptake and the others were positive on 201Tl scan, but without significant difference. NIS positive patients (1/8) with a papillary thyroid carcinoma had no 201Tl uptake, and the others were positive on 201Tl scan, but without significant difference. Whether the results of NIS staining and 201Tl scan were positive or not did not affect the responses of radioactive iodine therapy in our study. CONCLUSION: These results suggest that thallium-201 uptake may be correlated with hNIS expression in thyroid nodules
Adenoma ; Antibodies ; Diagnosis ; Goiter ; Humans ; Immunohistochemistry ; Iodine ; Ion Transport* ; Thyroid Gland* ; Thyroid Neoplasms ; Thyroid Nodule* ; Thyroiditis