Subclinical hypothyroidism (SCH), characterized by elevated serum thyroid-stimulating hormone (TSH) levels and normal free thyroxine levels, usually presents without symptoms, and is often discovered incidentally during routine blood test. The Task Force of the Korean Thyroid Association Committee of Clinical Practice Guidelines has established a guideline to evaluate and manage SCH; the guideline emphasizes the implementation of diagnostic criteria based on the TSH reference range for Koreans and focuses on the proven health benefits of levothyroxine (LT4) treatment. Based on the Korea National Health and Nutrition Examination Survey (2013-2015), serum TSH level of 6.8 mIU/L is considered the reference value for SCH. SCH can be categorized as mild (TSH 6.8-10.0 mIU/L) or severe (TSH ＞10.0 mIU/L), and patients are classified as adults (age ＜70 years) or elderly patients (age ≥70years) depending on the health effects of LT4 treatment. An initial increase in serum TSH levels should be reassessed with a subsequent measurement, along with the thyroid peroxidase antibody test, preferably 2-3 months after the initial evaluation. Usually, LT4 treatment is not recommended for mild SCH in adults; however, treatment is necessary for severe SCH in patients with underlying coronary artery disease or heart failure and can be considered for coexisting dyslipidemia. LT4 treatment is not recommended for mild or even severe SCH in elderly patients, in general. Patients with SCH who receive LT4 treatment, the LT4 dosage should be personalized, and serum TSH levels should be monitored to ensure optimal LT4 dosage (dosage that is neither excessive nor insufficient). Patients with SCH who do not receive LT4 treatment require periodic follow-up at appropriate testing intervals determined by disease severity. The guideline also provides several educational points applicable in clinical settings.

PURPOSE: The purpose of this report is to organize the history of Korean Mothersafe, a professional teratology information center. Throughout its domestic and international activities, Mothersafe has firm role to write journals and books, to provide counseling, to run educational courses on maternal and fetal toxicology, and so on. This paper delineates the achievements in last ten years and discusses the vision of Mothersafe. METHODS: In order to formulate the accomplishments of Korean Mothersafe, the volume of counseling calls are carefully reviewed by their contents, counselees, and the consultation results, etc. Textbooks and journals based on the data from Mothersafe are evaluated. Other roles of the Mothersafe, such as hosting symposium and running public programs are also noted. RESULTS: Korean Mothersafe provided 76,555 counseling to 45,933 expectant women and 30,622 breast-feeding women. The database has total 52,130 enrollments from 2010 to 2019. A total of 33 papers are published regarding medication, alcohol, smoking, radiation, etc. A specialized book on maternal-fetal toxicology was published and teratology part of obstetrics textbook was updated. Education programs and symposiums were held and primary care programs for expectant parents are run by Mothersafe. CONCLUSION Korean Mothersafe has contributed to safe environments for numerous pregnant and breast-feeding women regarding medication, drinking, smoking, and other hazardous substances. The huge database provided evidence for researches, textbooks and seminars, etc. Korean Mothersafe is now facing a new challenge to go forward through social dynamics with many issues regarding prevention and continuance of pregnancy, abortion, and so on.

Pheochromocytomas might be sporadic or genetic. Genetic pheochromocytoma is associated with multiple endocrine neoplasia (MEN) type 2A, MEN type 2B, and von Hippel-Lindau (VHL) disease. RET mutations are identified in more than 90% of index cases of MEN2 and familial medullary thyroid cancer and in about 4–12% of apparent sporadic cases. Here, we report a 54-year-old man presenting with pheochromocytoma and renal cell carcinoma, who was identified as having a novel missense RET mutation.
Carcinoma, Renal Cell ; Humans ; Male ; Middle Aged ; Multiple Endocrine Neoplasia ; Pheochromocytoma ; Thyroid Neoplasms

Follicular variant papillary thyroid cancer (FVPTC) is the second most common subtype after conventional PTC. We compared ultrasonographic (US) features of FVPTC to those of conventional PTC according to tumor size. We reviewed US findings, pathologic reports, and medical charts of 249 PTC patients with surgically proven disease (83 FVPTCs, 166 conventional PTCs) at our institution from January 2007 to December 2012. FVPTCs were divided into PTC-like and follicular neoplasm (FN)-like based on sonographic characteristics. PTC-like features were defined as having at least one malignant feature (taller-than-wide shape, infiltrative margin, marked hypoechogenicity, and micro-calcifications), whereas FN-like cancers showed oval solid features without malignant features. FVPTCs showed a higher rate of FN-like features than conventional PTCs. Of 166 conventional PTCs, 13 (7.8%) had FN-like features and 153 (92.2%) had PTC-like features, whereas of the 83 FVPTCs, 31 (37.3%) had FN-like features and 52 (62.7%) had PTC-like features. Macro-FVPTCs showed a higher rate of FN-like features than micro-FVPTCs (P < 0.001). Of 21 macro-FVPTCs, 18 (85.7%) had FN-like features and 3 (14.3%) had PTC-like features, whereas of the 62 micro-FVPTCs, 13 (21%) had FN-like features and 49 (79%) had PTC-like features. There were no differences in multifocality, extrathyroidal invasion, and lymph node metastasis between PTC-like FVPTCs and FN-like FVPTCs. FVPTCs showed fewer sonographic malignant features than conventional PTCs. In particular, FVPTCs larger than 1 cm had a more frequent benign sonographic appearance. Therefore, if fine-needle aspiration result is suspicious for PTC in a nodule larger than 1 cm with no suspicious US features, the possibility of FVPTC might be considered.
Adult ; Carcinoma, Papillary, Follicular/*diagnostic imaging/pathology ; Demography ; Female ; Humans ; Lymphatic Metastasis ; Male ; Middle Aged ; Neoplasm Staging ; Thyroid Neoplasms/*diagnostic imaging/pathology ; *Ultrasonography

Adrenal myelolipoma (AML) is a rare, usually benign, and nonfunctioning tumor. About 7-15% of adrenal incidentalomas are AMLs, composed of normal hematopoietic elements and mature adipose tissue. AML is usually unilateral and < 4 cm. It is often discovered incidentally on abdominal computed tomography or magnetic resonance imaging. It is related to a chronic increase in adrenocorticotropic hormone, such as that observed in patients with congenital adrenal hyperplasia, Cushing disease, Conn's syndrome, and pheochromocytoma. Here, we report a 28-year-old man diagnosed with non-salt-losing congenital adrenal hyperplasia with huge bilateral AMLs and a literature review.
Adipose Tissue ; Adrenal Hyperplasia, Congenital* ; Adrenocorticotropic Hormone ; Adult ; Humans ; Hyperaldosteronism ; Magnetic Resonance Imaging ; Myelolipoma* ; Pheochromocytoma ; Pituitary ACTH Hypersecretion

Neuroendocrine lesions of the thyroid are rare. The most common types are medullary thyroid carcinomas (MTCs) and C-cell hyperplasia. MTCs originate from thyroid parafollicular cells that secrete calcitonin which serves as a serum marker of MTCs. Here, the rare case of a calcitonin-negative neuroendocrine tumor (NET) derived from follicular lesions of the thyroid is described. A 34-year-old man presented at our hospital for the surgical management of an incidental thyroid nodule that was observed on an ultrasound sonography (USG) of the neck. Initially, USG-guided aspiration cytology was performed, and a MTC was suspected. The expressions of thyroglobulin and thyroid transcription factor-1, which are thyroid follicular cell markers, and synaptophysin and chromogranin A, which are neuroendocrine markers, was confirmed following surgical pathology. However, the staining of calcitonin, a marker of MTCs, was not observed. A nonmedullary NET of the thyroid is uncommon, and the distinction between calcitonin-negative NETs and MTCs of the thyroid may be important due to differences in their clinical courses and management.
Adult ; Calcitonin ; Carcinoma, Medullary ; Chromogranin A ; Humans ; Hyperplasia ; Neck ; Neuroendocrine Tumors* ; Pathology, Surgical ; Synaptophysin ; Thyroglobulin ; Thyroid Gland* ; Thyroid Neoplasms ; Thyroid Nodule ; Ultrasonography ; Biomarkers

BACKGROUND: A diagnostic whole-body scan (WBS) is recommended 6 to 12 months after total thyroidectomy and radioactive iodide ablation in intermediate- or high-risk patients with differentiated thyroid cancer (DTC). The aim of this study was to evaluate the necessity of a diagnostic WBS after radioactive iodide ablation in intermediate-risk patients with DTC. METHODS: A total of 438 subjects were included in the study: 183 low-risk subjects and 255 intermediate-risk subjects according to the American Thyroid Association guideline. All subjects diagnosed with DTC received 1,100 MBq (30 mCi) activity of radioiodine (I-131) following total thyroidectomy. On follow-up, all subjects underwent a diagnostic I-131 WBS after thyroid hormone withdrawal. RESULTS: After initial radioactive iodide ablation, 95.1% of low-risk patients and 91.4% of intermediate-risk patients showed no uptake on diagnostic WBS (P=0.135). Intermediate-risk patients with stimulated thyroglobulin (Tg) levels higher than 2.0 ng/mL showed a greater rate of radioactive iodine uptake on diagnostic WBS. Four intermediate-risk patients showed recurrence during the 16 to 80 months follow-up period. Three of the four patients with recurrence showed no uptake on diagnostic WBS and had a stimulated Tg level less than 2.0 ng/mL. CONCLUSION: A diagnostic I-131 WBS after radioactive iodide ablation in intermediate-risk patients with DTC may not be necessary. A large prospective study is necessary to determine the necessity of diagnostic WBS in intermediate-risk patients with DTC.
Follow-Up Studies ; Humans ; Iodides ; Iodine ; Radioactivity ; Recurrence ; Thyroglobulin ; Thyroid Gland* ; Thyroid Neoplasms* ; Thyroidectomy

Familial isolated primary hyperparathyroidism(FIPH) is associated with multiple endocrine neoplasia type 1 (MEN1) syndrome, primary hyperparathyroidism accompanied by jaw-tumor syndrome, and familial hypocalciuric hypercalcemia. FIPH may be an early stage of MEN1 or an allelic variant of MEN1. Thymic carcinoid tumor is a rare tumor in MEN1 syndrome. Here, the authors report the case of a 40-year-old man diagnosed with recurrent thymic carcinoid tumor and FIPH. Both the patient and his elder sister had been previously diagnosed to have FIPH with a novel frameshift mutation in the MEN1 gene. Initially, the patient underwent thymectomy because of an incidental finding of a mediastinal mass in his chest X-ray, and had remained asymptomatic over the following 4 years. Pancreas computed tomography conducted to evaluate MEN1 syndrome revealed anterior and middle mediastinal masses, and resultantly, massive mass excision was performed. Histological findings disclosed atypical carcinoids with infiltrative margins. In view of the thymic carcinoid tumor relapse that occurred in this patient, the authors recommend that regular pancreas and pituitary imaging studies be conducted for FIPH associated with a MEN1 gene mutation.
Adult ; Carcinoid Tumor* ; Frameshift Mutation ; Humans ; Hypercalcemia ; Hyperparathyroidism ; Hyperparathyroidism, Primary* ; Incidental Findings ; Multiple Endocrine Neoplasia Type 1 ; Pancreas ; Recurrence ; Siblings ; Thorax ; Thymectomy

The occurrence of Graves' disease following subacute thyroiditis (SAT) is rare. The pathophysiology of it is not well known. We report a case of Graves' disease following SAT presented with creeping. A 45-year-old woman presented with neck pain, and thyrotoxic symptoms. Neck pain migrated from left lobe to right lobe of the thyroid. Thyroid scan revealed decreased uptake in the both lobes except the superior portion of the right thyroid gland. Initially, the patient was diagnosed with SAT and treated with steroid therapy. Four months later, thyroid function test showed suppressed thyroid-stimulating hormone (TSH), elevated free thyroxine (T4) and TSH receptor antibody. Thyroid scan revealed increased uptake compatible with Graves' disease. The autoimmune alteration after SAT may lead to the development of Graves' disease in the susceptible patients. These patients should be monitored for the development of Graves' disease.
Female ; Graves Disease* ; Humans ; Middle Aged ; Neck Pain ; Receptors, Thyrotropin ; Thyroid Function Tests ; Thyroid Gland ; Thyroiditis, Subacute* ; Thyrotropin ; Thyroxine